1984 / Animal Study / Preliminary evidenceA screening of 32 cannabinoids in rabbits found that certain THC derivatives outperformed THC itself at lowering eye pressure, and non-THC compounds also showed activity.
1986 / Pilot Study / Preliminary evidenceFive dystonia patients improved 20-50% on oral CBD up to 600 mg/day, but two with coexisting Parkinson's features experienced worsened tremor and slowed movement.
1991 / Randomized Controlled Trial / Moderate evidenceCBD at approximately 700 mg/day for six weeks showed no significant benefit for Huntington's Disease symptoms in 15 patients, but was well tolerated with no toxicity.
1991 / Observational / Preliminary evidenceOral CBD at 700 mg/day produced mean plasma levels of only 5.9-11.2 ng/mL with a 2-5 day elimination half-life. No THC was detected, confirming CBD does not convert to THC.
2000 / Animal Study / Strong evidencePublished in PNAS, CBD blocked arthritis progression in mice when given after symptoms started, protected joints, and worked through multiple anti-inflammatory mechanisms at an optimal oral dose of 25 mg/kg.
2001 / Review / Preliminary evidenceConference report showing whole cannabis extracts outperformed single cannabinoids for spasticity in animal models, while UK clinical trials for pain and multiple sclerosis were underway.
2001 / Review / Moderate evidenceA review by THC discoverer Raphael Mechoulam tracing cannabinoids from ancient use to modern clinical applications in nausea, appetite, multiple sclerosis, arthritis, and neuroprotection.
2002 / Randomized Controlled Trial / Moderate evidenceRandomized trial in 16 MS patients found neither oral THC nor cannabis extract reduced spasticity, and both worsened patients' overall impression compared to placebo.
2003 / Review / Moderate evidenceGW Pharmaceuticals developed Sativex and other cannabis medicines, with phase III trials showing significant neuropathic pain reduction in MS, leading to licensing with Bayer AG.
2003 / Randomized Controlled Trial / Moderate evidenceControlled trial showing sublingual cannabis extracts (THC and CBD) significantly improved pain and bladder symptoms in 24 patients with treatment-resistant neurological conditions.
2003 / Animal Study / Moderate evidencePreclinical study showing whole cannabis extracts produced faster spasticity relief and more potent anticonvulsant effects than pure THC, with THC-free extracts also showing anticonvulsant activity.
2004 / Randomized Controlled Trial / Moderate evidenceRandomized trial in 48 patients finding cannabis sprays produced statistically significant neuropathic pain and sleep improvements, though below the predefined clinical significance threshold.
2004 / Pilot Study / Preliminary evidenceOpen-label pilot finding cannabis extracts significantly improved bladder urgency, incontinence, frequency, and nocturia in 15 MS patients with treatment-resistant symptoms.
2004 / Review / Moderate evidencePharmacology review mapping CB1 and CB2 receptor distribution and cataloging 13 therapeutic properties of cannabinoids including analgesia, neuroprotection, and antitumor effects.
2004 / Randomized Controlled Trial / Moderate evidenceSleep study finding 15 mg THC was sedating while 15 mg CBD had alerting properties and counteracted THC sedation, with EEG showing CBD increased wakefulness during sleep.
2004 / Randomized Controlled Trial / Moderate evidence34 individual patient trials of sublingual cannabis extracts for chronic pain found THC-containing formulations most effective, with wide dosing needs and acceptable side effects.
2004 / Review / Moderate evidenceCritical review distinguishing between oral THC (failed to reduce spasticity objectively) and sublingual THC:CBD (showed more promise) for MS treatment.
2004 / Randomized Controlled Trial / Moderate evidenceCrossover trial of 57 MS patients found cannabis extract capsules significantly reduced spasm frequency and improved mobility in the 37 patients who took at least 90% of their dose.
2004 / Randomized Controlled Trial / Moderate evidenceTrial of 160 MS patients found Sativex spray significantly reduced spasticity (P = 0.001) but the primary composite symptom measure did not reach significance.
2005 / Review / Moderate evidenceReview of 15 randomized clinical trials found the strongest evidence for cannabinoids treating MS spasticity, Tourette's tics, and neuropathic pain, while trials for cachexia and Parkinson's were negative.
2005 / Randomized Controlled Trial / Moderate evidenceControlled study of 23 marijuana users found varying CBC and CBD concentrations did not change the effects of smoked marijuana, confirming THC as the primary active ingredient.
2005 / Randomized Controlled Trial / Moderate evidenceDouble-blind crossover study of 24 volunteers found CBD partially inhibits THC liver metabolism, though the effect was small relative to natural variation, and women achieved significantly higher THC blood levels than men.
2005 / Review / Moderate evidenceFive RCTs of Sativex (THC:CBD spray) in 368 neurological patients showed significant benefits for neuropathic pain, spasticity, and sleep, leading to approval in Canada for MS pain.
2005 / Randomized Controlled Trial / Strong evidenceRandomized trial of 66 MS patients found THC:CBD spray significantly reduced central neuropathic pain (P = 0.005) and sleep disturbance (P = 0.003) with 97% completion rate.
2005 / Review / Moderate evidenceReview found cannabis-based MS medicines had mild side effects in trials but urged caution for psychosis-prone and pregnant patients, noting therapeutic benefits remained modest.
2006 / Review / Moderate evidenceClinical review of Sativex shows patients typically use 8-12 sprays daily (22-32 mg THC + 20-30 mg CBD), with positive trial results for MS spasticity and neuropathic pain.
2006 / Animal Study / Preliminary evidenceCell study found CBD blocked inflammation pathways (p38 MAP kinase, NF-kappaB) triggered by Alzheimer's-associated beta-amyloid protein, adding to evidence of CBD's neuroprotective properties.
2006 / Animal Study / Preliminary evidenceCBD-rich cannabis extract reversed THC-induced memory deficits but failed to reverse memory impairments caused by anticholinergic or antiglutamatergic drugs, suggesting CBD's effects are cannabinoid-system specific.
2006 / Randomized Controlled Trial / Strong evidenceCAMS substudy found cannabis extract reduced MS urinary incontinence by 38% and THC by 33%, both significantly better than placebo (18%), despite the main study finding no spasticity benefit.
2006 / Animal Study / Preliminary evidenceCell study found prolonged THC and CBD exposure reduced drug-resistance protein expression in leukemia cells, increasing their sensitivity to the chemotherapy drug vinblastine.
2006 / Review / Moderate evidenceReview of Sativex clinical development shows efficacy across multiple pain conditions, rheumatoid arthritis, and MS symptoms, with no significant intoxication, tolerance, or withdrawal reported.
2006 / Randomized Controlled Trial / Moderate evidenceSmall crossover trial found sublingual THC (5 mg) temporarily lowered eye pressure in glaucoma patients for 2 hours, while CBD had no benefit and higher doses transiently raised eye pressure.
2006 / Observational / Moderate evidenceLong-term open-label study of 137 MS patients found Sativex maintained its effects over 434 days without tolerance, and planned 2-week interruption showed no consistent withdrawal syndrome.
2006 / Animal Study / Preliminary evidenceCBD reduced autoimmune diabetes incidence from 86% to 30% in mice by shifting the immune response from harmful Th1 to protective Th2 patterns and reducing pancreatic inflammation.
2007 / Animal Study / Preliminary evidenceCBD reduced heart attack damage by 66% in rats and dramatically lowered inflammation markers, but the effect required a living system and didn't work in isolated hearts.
2007 / Animal Study / Preliminary evidenceCBD activated mast cells in lab tests through an unknown mechanism, behaving opposite to synthetic cannabinoids that suppressed them, suggesting undiscovered cannabinoid receptors exist.
2007 / Animal Study / Preliminary evidenceA single CBD dose before allergen exposure significantly suppressed antibody production, immune cell cytokine output, and T-cell proliferation in mice.
2007 / Randomized Controlled Trial / Moderate evidenceCannabis extract with CBD enhanced automatic brain responses to auditory changes, while pure THC alone did not, suggesting CBD may protect cognitive processing.
2008 / Randomized Controlled Trial / Moderate evidencefMRI study found THC weakened brain activation in impulse control regions (right frontal, anterior cingulate) while CBD affected entirely different areas, independent of intoxication.
2008 / Animal Study / Moderate evidenceCBD selectively normalized gut hypermotility in mice with intestinal inflammation without affecting normal movement, working through CB1 receptors and the FAAH enzyme.
2008 / Animal Study / Moderate evidenceSix plant cannabinoids activated the pain-sensing TRPA1 channel (CBC most potent at 60 nM) and blocked the cold-sensing TRPM8 channel, revealing non-CB1/CB2 mechanisms for pain relief.
2008 / Animal Study / Preliminary evidenceIn mice, high-dose CBD unexpectedly amplified low-dose THC's behavioral effects by increasing CB1 receptor expression, challenging the assumption that CBD always counteracts THC.
2008 / Animal Study / Moderate evidenceCBD suppressed T cell function through NFAT/AP-1 transcription factor disruption, and this occurred independently of both CB1 and CB2 cannabinoid receptors.
2008 / Review / Strong evidenceThe definitive pharmacological characterization of THC, CBD, and THCV — showing that three molecules from the same plant have completely different, sometimes opposite, effects at cannabinoid receptors.
2008 / Randomized Controlled Trial / Moderate evidenceCrossover study found THC reduced the P300 attention brain wave, and a cannabis extract with CBD failed to reverse this effect, complicating the "CBD counteracts THC" narrative.
2009 / Animal Study / Preliminary evidenceCBD enhanced glycine receptor function at low micromolar concentrations and directly activated them at higher concentrations, providing a non-cannabinoid mechanism for pain relief.
2009 / Randomized Controlled Trial / Preliminary evidenceTHC disrupted brain activation in the parahippocampal gyrus and ventrostriatum during verbal learning, with ventrostriatal changes correlating with psychotic symptoms. CBD had no such effects.
2009 / Review / Moderate evidenceA review found that all classes of cannabinoids show anti-inflammatory activity, potentially through promoting inflammation resolution rather than blocking its initiation.
2009 / Observational / Preliminary evidenceIn 20 MS patients, Sativex did not improve spasticity on clinical or neurophysiological measures and did not alter endocannabinoid system markers in peripheral blood.
2009 / Randomized Controlled Trial / Preliminary evidenceIn 15 men, THC increased anxiety and skin conductance responses to fearful faces, while CBD reduced amygdala activation and autonomic arousal, demonstrating opposite emotional processing effects.
2009 / Animal Study / Preliminary evidenceIn rats, 14 days of CBD reduced T cells, B cells, and white blood cells at 5 mg/kg while sparing natural killer cells. A lower dose actually increased NKT cells.
2009 / Review / Moderate evidenceA review found that CBD demonstrates neuroprotective and anti-inflammatory properties in preclinical studies, making it a promising candidate for neurodegenerative disorders with few existing treatments.
2009 / Systematic Review / Moderate evidenceA systematic review of six RCTs found combined THC/CBD extracts showed a trend toward reduced MS spasticity, with significant subjective improvement but no significant changes on objective clinical measures.
2009 / Animal Study / Preliminary evidenceCBD (20 mg/kg) reversed THC-induced social withdrawal in rats at low doses, but the combination of high doses of both compounds impaired social interaction, possibly through sedation.
2009 / Animal Study / Preliminary evidenceCBD (5 mg/kg daily) reduced bone loss, inflammatory cytokines, and RANKL/RANK expression in rats with experimentally induced periodontal disease over 30 days.
2009 / Review / Moderate evidenceRCTs found no objective Ashworth scale improvement with cannabinoids for MS spasticity, but patients reported significant improvement in spasticity (p=0.01), spasms, sleep, and pain.
2010 / Randomized Controlled Trial / Moderate evidenceTHC and CBD had opposite effects on brain activation in the striatum, hippocampus, amygdala, and cortex across four cognitive tasks, and CBD pretreatment blocked THC-induced psychosis in 6 volunteers.
2010 / Randomized Controlled Trial / Preliminary evidenceIn a small pilot trial, 71% of cancer patients receiving a THC/CBD spray achieved complete response for delayed chemo nausea versus 22% on placebo, added to standard anti-emetic therapy.
2010 / Animal Study / Preliminary evidenceA single amino acid mutation in the glycine receptor completely abolished the ability of CBD, ajulemic acid, and HU210 to modulate this pain-related receptor, identifying a critical molecular interaction site.
2010 / Randomized Controlled Trial / Preliminary evidenceCBD disrupted the forward neural connection between the amygdala and anterior cingulate during fear processing, the first demonstration that CBD affects brain network dynamics, not just regional activation.
2010 / Randomized Controlled Trial / Moderate evidenceIn 177 cancer patients with opioid-refractory pain, THC/CBD spray significantly reduced pain (43% responders vs 21% placebo), while THC alone did not reach significance, highlighting CBD importance in the formulation.
2010 / Systematic Review / Moderate evidenceSystematic review of 41 brain imaging studies found cannabis affected brain function, especially prefrontal blood flow, but caused minimal structural changes.
2010 / Animal Study / Preliminary evidenceCBD reduced cardiac dysfunction, inflammation, fibrosis, oxidative stress, and cell death in diabetic mice and human heart cells exposed to high glucose.
2010 / Review / Moderate evidenceReview found cannabis-based medicines improved patient-reported MS spasticity but often did not show effects on the Ashworth clinical scale.
2011 / Randomized Controlled Trial / Moderate evidence600 mg CBD normalized public speaking anxiety in social phobia patients to healthy control levels — no sedation, no cognitive impairment. The foundational CBD anxiety study.
2011 / Review / Moderate evidenceReview found Sativex (THC+CBD) matched baclofen effectiveness for MS spasticity in mice, with endocannabinoid levels altered in both MS animal models and patient cerebrospinal fluid.
2011 / Animal Study / Preliminary evidenceCBD reduced Alzheimer's-related brain inflammation and stimulated new neuron growth in rats, both through the PPARgamma receptor pathway.
2011 / Randomized Controlled Trial / Moderate evidenceIn 9 cannabis smokers, Sativex and oral THC at equivalent doses produced similar mild effects with no evidence that CBD attenuated THC's side effects at therapeutic doses.
2011 / Randomized Controlled Trial / Moderate evidenceTHC blood levels were nearly identical whether given as Sativex (with CBD) or as pure oral THC, ruling out pharmacokinetic interaction at therapeutic doses.
2011 / Animal Study / Preliminary evidenceCBD reduced MS-like disease severity in mice by suppressing pathogenic T cells and microglial activation through mechanisms independent of CB1 and CB2 receptors.
2011 / Review / Moderate evidenceReview of how cannabinoids regulate nausea and vomiting, finding both THC and CBD effective through different brain mechanisms.
2011 / Randomized Controlled Trial / Preliminary evidenceTiny pilot found cannabis extract may change how COPD patients perceive breathlessness without affecting standard measurements.
2011 / Review / Moderate evidenceReview of Sativex clinical data found low intoxication, 2.2% euphoria rate, no tolerance, and no withdrawal, suggesting low abuse potential.
2011 / Review / Moderate evidenceThe most cited paper in cannabis science: Russo's comprehensive review mapping potential terpene-cannabinoid synergies. Coined the framework for the 'entourage effect' as applied to plant medicine. THC-CBD synergy is confirmed; terpene interactions remain debated.
2011 / Animal Study / Preliminary evidenceRat study showed 1:1 THC:CBD combination protected brain cells from Huntington's disease-like damage through antioxidant mechanisms.
2011 / Review / Moderate evidenceReview of Sativex clinical trials for MS spasticity showing reduced symptom severity with manageable side effects.
2011 / Randomized Controlled Trial / Moderate evidenceIn 23 cannabis users, Sativex showed similar or slightly less abuse potential than equivalent doses of dronabinol (pure synthetic THC).
2011 / Animal Study / Preliminary evidenceCBD reversed amphetamine-induced oxidative brain damage and increased BDNF in rats, suggesting potential neuroprotective properties relevant to bipolar disorder.
2011 / Review / Strong evidenceThree pivotal trials totaling over 1,000 MS patients showed Sativex consistently reduced spasticity with mild, transient side effects and no abuse potential.
2011 / Randomized Controlled Trial / Moderate evidenceBrain imaging showed THC and CBD had opposite effects on auditory processing regions, with THC's disruption correlating with psychotic symptoms.
2012 / Review / Moderate evidenceUK drug bulletin reviewed Sativex as add-on therapy for MS spasticity when other treatments have failed, requiring demonstration of initial response.
2012 / Animal Study / Preliminary evidencePharmacokinetic study showing four lesser-known cannabinoids (CBD, CBDV, THCV, CBG) all cross the blood-brain barrier, with CBD reducing OCD-like behavior in mice.
2012 / Randomized Controlled Trial / Preliminary evidenceIn 9 volunteers, unheated cannabis extract produced nearly double the CBD blood levels and different metabolic profiles compared to heated extract.
2012 / Review / Strong evidenceReview noting over 100 controlled trials since 1975 supporting cannabinoid therapeutics, with three approved medicines and manageable side effects.
2012 / Review / Moderate evidenceReview confirming clinical trial evidence for Sativex in MS spasticity, with biological rationale from endocannabinoid system science.
2012 / Review / Moderate evidenceEconomic modeling found Sativex cost 49,300 pounds per QALY for MS spasticity, exceeding the UK's 30,000-pound cost-effectiveness threshold.
2012 / Randomized Controlled Trial / Moderate evidenceIn the same 16 men, oral THC caused anxiety, psychotic symptoms, and sedation, while 600 mg CBD was indistinguishable from placebo.
2012 / Animal Study / Preliminary evidenceCBD protected myelin-producing brain cells from inflammatory death by reducing ER stress through a mechanism independent of known cannabinoid receptors.
2012 / Animal Study / Preliminary evidenceA new class of chemical compounds can selectively block endocannabinoid-degrading enzymes in the brain, potentially offering pain and mood benefits without full psychoactive effects.
2012 / Review / Moderate evidenceReview of clinical trial data found Sativex (THC/CBD spray) reduced MS spasticity symptoms and improved patients' ability to perform daily activities.
2012 / Review / Moderate evidenceReview found nabiximols (THC/CBD spray) effectively treated spasticity, pain, and bladder dysfunction in MS, though long-term data were limited.
2012 / Animal Study / Preliminary evidenceA single dose of CBD reduced lung inflammation across multiple markers in mice, working through the adenosine A2A receptor pathway.
2012 / Animal Study / Preliminary evidenceCBD suppressed vomiting and nausea-like behavior in animals by activating serotonin 5-HT1A receptors in a specific brainstem region.
2012 / Review / Preliminary evidencePreclinical evidence showed cannabinoids, especially the THC/CBD combination in Sativex, had neuroprotective properties relevant to Huntington's disease.
2012 / Animal Study / Preliminary evidenceA THC/CBD combination reduced brain cell death and inflammation in a rat Huntington's disease model, working through both CB1 and CB2 receptors.
2012 / Systematic Review / Moderate evidenceSystematic review of 34 human studies found preliminary CBD benefits for anxiety, insomnia, and epilepsy, with complex THC interactions depending on delivery route.
2013 / Review / Preliminary evidenceReview found growing preclinical evidence for cannabinoid anticancer effects across multiple cancer types, but contradictory results and unclear mechanisms limit conclusions.
2013 / Case Report / Preliminary evidenceA 19-year-old heavy cannabis user showed no withdrawal, anxiety, or dissociative symptoms during 10 days of CBD treatment for cannabis withdrawal syndrome.
2013 / Randomized Controlled Trial / Strong evidencePre-treatment with 600 mg CBD reduced THC-induced paranoia (OR=0.22) and eliminated memory impairment (-0.4% vs. -10.6% decline) in healthy volunteers.
2013 / Animal Study / Moderate evidenceTopical THC reduced allergic skin inflammation in mice by suppressing immune signaling, working independently of the CB1 and CB2 cannabinoid receptors.
2013 / Animal Study / Moderate evidenceTHC and CBD suppressed the autoimmune Th17 response (IL-17, IL-6) while CBD boosted anti-inflammatory IL-10, through a novel receptor-independent mechanism.
2013 / Cross Sectional / Preliminary evidenceParent survey found 84% of children with treatment-resistant epilepsy had reduced seizures with CBD-enriched cannabis, after trying an average of 12 medications.
2013 / Systematic Review / Moderate evidenceComprehensive review identified CBD-enriched cannabis among 21 plant medicines with clinical anxiety evidence, alongside kava, chamomile, passionflower, and others.
2013 / Randomized Controlled Trial / Moderate evidenceA Phase I trial found that THC/CBD oral spray produced peak blood levels well below those from smoking, with no buildup after nine days of repeated dosing.
2013 / Cross Sectional / Moderate evidenceAnalysis of 232 cannabis samples seized in Australia found high average THC (14.88%) and nearly absent CBD (0.14%), confirming global trends toward high-potency, low-CBD cannabis.
2013 / Case Report / Preliminary evidenceA patient with treatment-resistant stiff-person syndrome showed quality of life improvement across all measured dimensions after 14 months of THC/CBD oral spray.
2014 / Review / Moderate evidenceIndependent review found THC/CBD oral spray provided meaningful spasticity relief for about 10% of MS patients not adequately helped by standard medications.
2014 / Randomized Controlled Trial / Strong evidenceA clinical trial found nabiximols (THC/CBD spray) significantly reduced cannabis withdrawal and improved treatment retention, but provided no long-term advantage over placebo for reducing cannabis use.
2014 / Review / Moderate evidenceExpert review found clinical evidence for cannabinoids in MS spasticity, refractory pain, and nausea, with emerging evidence for epilepsy, dystonia, tics, and other neurological conditions.
2014 / Review / Moderate evidenceLeading epilepsy researchers outlined the case for clinical trials of pure CBD in treatment-resistant epilepsy, citing strong preclinical evidence and apparent tolerability.
2014 / Review / Moderate evidenceLandmark review found CBD showed anticonvulsant, anxiolytic, antipsychotic, and anti-addictive properties but lacked well-powered trials, setting the stage for the clinical program that led to FDA approval.
2014 / Observational / Moderate evidencePost-marketing data from the UK, Germany, and Spain confirmed THC/CBD spray effectiveness for MS spasticity (41% response rate) with no abuse signal or driving impairment.
2014 / Review / Strong evidencePhase III trials confirmed THC/CBD spray helped about one-third of treatment-resistant MS spasticity patients, with no cognition or mood effects after 50 weeks of use.
2014 / Review / Moderate evidenceReview found cannabinoids showed potential for multiple neurological diseases, with established uses in MS, nausea, and appetite stimulation, and emerging evidence for neurodegenerative conditions.
2014 / Systematic Review / Strong evidenceThe AAN systematic review found oral cannabis extract effective for MS spasticity and pain, but ineffective for tremor and of unknown efficacy for epilepsy (pre-CBD trials).
2014 / Case Report / Preliminary evidenceCharlotte Figi: 50 seizures/day to 2-3/month on CBD cannabis extract. Single case that launched a movement, a drug approval, and a national policy shift.
2014 / Randomized Controlled Trial / Moderate evidencePilot study found Sativex patients had oral fluid THC over 5,356 ng/mL shortly after dosing, remaining detectable for 2+ hours, with primary roadside test often giving false negatives.
2014 / Randomized Controlled Trial / Moderate evidenceTwelve-week study of 48 laying hens found hempseed (up to 30%) and hempseed oil (up to 9%) had no negative effects on performance, egg quality, or blood chemistry.
2014 / Review / Moderate evidenceReview describes how GW Pharmaceuticals manages cannabis variability in genetics, growing, harvesting, and processing to produce Sativex, the first UK-approved cannabis medicine.
2014 / Observational / Preliminary evidenceAdding hempseed press-cake to gluten-free crackers increased fiber by up to 249% and provided 14.1g protein and 3.2g omega-3 per 100g in the optimized formulation.
2014 / Review / Moderate evidenceReview of data from 1,000+ MS patients found Sativex did not cause cognitive decline at 12 months, did not impair driving, and maintained effectiveness at lower real-world doses.
2014 / Review / Moderate evidenceReview presents evidence that CBD could serve as an antipsychotic agent through non-dopamine mechanisms, potentially augmenting standard medications and addressing metabolic and inflammatory components of schizophrenia.
2014 / Review / Moderate evidenceBroad review of cannabinoid medicine covered therapeutic potential in MS spasticity, pain, nausea, epilepsy, psychosis, and addiction, contrasting THC and CBD pharmacology.
2014 / Randomized Controlled Trial / Strong evidenceRCT of 246 neuropathic pain patients found THC/CBD spray achieved significant 30% pain response rates (p=0.034) and improved sleep quality versus placebo.
2014 / Systematic Review / Moderate evidenceSystematic review mapped cannabinoid metabolism by liver enzymes (THC via CYP2C9/3A4, CBD via CYP2C19/3A4) and found generally low drug interaction risk at typical doses.
2014 / Review / Strong evidenceComprehensive drug review confirmed Sativex significantly reduces MS spasticity in patients who respond to an initial 4-week trial, with early dizziness and fatigue as main side effects.
2014 / Review / Moderate evidenceReview of CBD for epilepsy found strong preclinical support for endocannabinoid system involvement in seizure control and growing anecdotal evidence for CBD, but called for rigorous clinical trials.
2014 / Randomized Controlled Trial / Moderate evidenceFirst human study of THCV found it increased brain responses to both food reward and aversion, suggesting potential for obesity treatment without the depressive effects of rimonabant.
2014 / Review / Strong evidenceAAN guidelines gave Level A (highest) recommendation for oral cannabis extract for MS spasticity symptoms and pain, while noting ineffectiveness for objective spasticity measures.
2014 / Systematic Review / Strong evidenceOfficial AAN guideline recommends oral cannabis extract for MS spasticity symptoms and pain (Level A), with Sativex for symptoms/pain/urinary frequency (Level B).
2015 / Review / Moderate evidenceReview proposes nabiximols (THC/CBD spray) as cannabinoid replacement therapy for cannabis dependence, analogous to methadone for opioid dependence, with controlled dosing and pharmaceutical standardization.
2015 / Randomized Controlled Trial / Moderate evidenceBrain imaging showed THC and CBD had opposite effects on connectivity between prefrontal, striatal, and hippocampal regions involved in salience processing and attention.
2015 / Review / Preliminary evidence2015 review: CBD was linked to lower anxiety in acute tests. Long-term treatment evidence in diagnosed patients was thin.
2015 / Review / Moderate evidenceReview of cannabinoid effects on brain immunity found anti-inflammatory properties relevant to MS, Alzheimer's, and ALS, with CB2 receptors as promising non-psychoactive targets.
2015 / Animal Study / Preliminary evidenceCBD treatment increased survival, prevented memory deficits, and reduced brain inflammation in mice with cerebral malaria by lowering cytokines and increasing BDNF.
2015 / Review / Moderate evidenceReview of THC/CBD spray trials for MS spasticity found ~1.27-point improvement over placebo on a 10-point scale, with carryover effects potentially underestimating true treatment benefit.
2015 / Animal Study / Preliminary evidenceTopical 1% CBD cream reduced EAE clinical scores from 5.0 to 1.5, recovered paralysis, and decreased brain inflammation, demyelination, and immune cell infiltration in mice.
2015 / Animal Study / Preliminary evidenceCBD reversed social withdrawal, cognitive deficits, and brain inflammation (astrocyte and microglial activation) in a schizophrenia mouse model, matching clozapine's effectiveness.
2015 / Animal Study / Preliminary evidenceNovel CBD derivative HU-444 reduced arthritis severity, liver inflammation, and TNF-alpha production in mice without psychoactive effects and without the ability to convert to THC.
2015 / Animal Study / Preliminary evidenceCBD triggered immune-suppressive cell mobilization in mice through mast cells and PPAR-gamma receptor activation, revealing a specific molecular pathway for CBD's immune effects.
2015 / Randomized Controlled Trial / Moderate evidenceIn a 4-way crossover study of 48 cannabis users, CBD improved and THC impaired emotional face recognition, with their combination preventing impairment.
2015 / Longitudinal Cohort / Moderate evidenceTHC/CBD spray maintained neuropathic pain relief (6.9 to 4.2 on 10-point scale) over 38 weeks in 380 patients without dose escalation, with 62% completing the study.
2015 / Cross Sectional / Preliminary evidenceParent survey of 117 children with epilepsy reported 85% seizure reduction with CBD products, but the study authors explicitly warned of severe participation bias and lack of controls.
2015 / Review / Moderate evidenceReview found CBD and other non-psychoactive cannabinoids inhibited multiple cancer types in animal models through diverse mechanisms and enhanced standard chemotherapy drug activity.
2015 / Review / Moderate evidenceReview found cannabinoids may counter chemotherapy-induced nausea, bone loss, kidney damage, heart damage, pain, and insomnia, based on preclinical and early clinical evidence.
2015 / Animal Study / Preliminary evidenceCBG was the most effective non-psychoactive cannabinoid at reducing bladder contractions in mice and human tissue, working through a non-CB1/CB2 mechanism.
2015 / Review / Moderate evidenceReview mapped non-psychoactive cannabinoid strategies for cancer treatment, including CB2-selective agents and enzyme inhibitors from both cannabis and non-cannabis plants.
2015 / Retrospective Cohort / Preliminary evidenceAmong 75 children given cannabis extracts for epilepsy, parents reported 33% had seizures cut in half, with dramatic differences by syndrome type. But 44% had side effects including worsened seizures.
2015 / Animal Study / Preliminary evidenceSynthetic CBD slowed MS-related disability in mice possibly via sodium channels, while THC slowed progression without suppressing relapses. A clinical trial subgroup also showed THC benefit.
2015 / Review / Moderate evidenceReview found cannabis constituents and FAAH inhibitors could complement MS treatment through dual symptom relief and anti-inflammatory/neuroprotective mechanisms.
2015 / Animal Study / Preliminary evidenceAll tested cannabinoids, including THC, CBD, and endocannabinoids, inhibited brain mitochondrial energy production through a mechanism independent of cannabinoid receptors.
2016 / Review / Moderate evidenceCannabis and tobacco smoke both induce CYP1A2 (additively), THC and CBD are primarily metabolized by CYP3A4, and CBD may inhibit CYP2C19, all with implications for drug interactions.
2016 / Review / Moderate evidenceA pharmacology review explained how CBD can reduce some of THC's psychoactive effects, a relationship that led to the development of the THC/CBD drug Nabiximols.
2016 / Review / Moderate evidenceCannabinoids modestly reduce cancer pain and are useful backup antiemetics, dronabinol improves taste disturbances, and preclinical data show anticancer potential through multiple mechanisms.
2016 / Review / Preliminary evidenceA theoretical review proposed cannabinoids as potential psoriasis treatments based on the endocannabinoid system's intersection with immune and nervous system pathways involved in the disease.
2016 / Pilot Study / Moderate evidenceThe clinical program that turned CBD into the first FDA-approved cannabis-derived drug. Open-label trial: 214 patients, 36.5% seizure reduction. NEJM RCT: 120 Dravet patients, seizures dropped from 12.4 to 5.9/month vs placebo (p=0.01). Epidiolex approved June 2018.
2016 / Observational / Moderate evidenceReal-world registry and observational data from over 1,100 patients across four European countries showed the THC:CBD spray Sativex had strong continuation rates and no evidence of addiction during long-term MS spasticity treatment.
2016 / Randomized Controlled Trial / Moderate evidenceA rigorous multi-site trial found that oral CBD at doses up to 800 mg did not reduce the high, reinforcing effects, or cardiovascular impact of smoked cannabis in regular users.
2016 / Randomized Controlled Trial / Moderate evidencePost hoc analysis of a clinical trial showed Sativex improved MS spasticity regardless of whether patients had failed one or both standard antispasticity medications.
2016 / Randomized Controlled Trial / Moderate evidenceIn a 13-week pilot trial, the minor cannabinoid THCV significantly lowered fasting blood sugar and improved beta-cell function in type 2 diabetes patients, while CBD had more modest effects and combinations were ineffective.
2016 / Randomized Controlled Trial / Moderate evidenceFirst rigorous study shows THC acutely reduces motivation temporarily, while cannabis dependence is associated with impaired reward learning but preserved overall motivation when sober.
2016 / Case Report / Preliminary evidenceA treatment-resistant epilepsy patient experienced dramatic seizure reduction with cannabis, and lab experiments suggest the rare cannabinoid CBDV may contribute through effects on the brain's inhibitory GABA system.
2016 / Review / Moderate evidenceCritical review finds CBD demonstrated antipsychotic effects comparable to standard medication in a clinical trial, with a side effect profile similar to placebo, potentially working through endocannabinoid system modulation.
2016 / Retrospective Cohort / Moderate evidenceMulticenter Israeli study found 89% of 74 children with severe, treatment-resistant epilepsy (failed 7+ drugs) had seizure reduction with CBD-enriched cannabis oil, with 18% achieving 75-100% reduction.
2016 / Animal Study / Moderate evidenceBoosting anandamide levels completely reversed social impairment in two autism mouse models (BTBR and Fragile X) through CB1 receptors, identifying FAAH as a novel therapeutic target for ASD.
2016 / Review / Moderate evidenceReview showing cannabinoids reduce inflammation through mechanisms different from NSAIDs, with several compounds in clinical development for chronic inflammatory and fibrotic diseases.
2017 / Narrative Review / Preliminary evidenceACOG's 2017 committee opinion formally recommended against cannabis use during pregnancy and lactation based on neurodevelopment concerns and insufficient safety data.
2017 / Randomized Controlled Trial / Moderate evidenceControlled study showing oral CBD up to 800mg produced no abuse-related effects in frequent marijuana users, supporting CBD's favorable safety profile.
2017 / Narrative Review / Preliminary evidenceReview of cannabis and sleep research through 2017 found CBD promising for insomnia, THC mixed (faster onset but worse quality), and the whole field still in its infancy.
2017 / Review / Moderate evidenceReview of five clinical studies found some evidence that THC and CBD formulations reduce cancer pain, with effective doses as low as 2.7mg THC plus 2.5mg CBD, but the evidence base remains small.
2017 / Review / Moderate evidenceReview of how GW Pharmaceuticals and the University of Mississippi produce consistent, medical-grade cannabis for clinical research, covering breeding, cultivation, and extraction.
2017 / Review / Moderate evidenceAmong 10 medicinal plants reviewed for MS, cannabis had the strongest clinical evidence, with demonstrated efficacy for spasticity, fatigue, urinary symptoms, and tremor.
2017 / Narrative Review / Moderate evidenceExpert review finding that cannabinoids may help IBD symptoms like pain and diarrhea, but clinical evidence remains insufficient for evidence-based treatment guidelines.
2017 / Systematic Review / Strong evidenceUmbrella review of 11 systematic reviews finding limited evidence for THC/CBD spray in neuropathic pain and inadequate evidence for cannabinoids in cancer pain, rheumatic pain, or anorexia.
2017 / Animal Study / Preliminary evidenceMouse study showing that boosting anandamide (via FAAH inhibition) reduced panic-like flight responses while boosting 2-AG (via MAGL inhibition) increased them, revealing distinct roles for the two endocannabinoids.
2017 / Narrative Review / Moderate evidenceReview finding that the endocannabinoid system helps fight infections, but cannabis use generally increases infection susceptibility by suppressing immune responses.
2017 / Narrative Review / Moderate evidenceReview finding cannabis compounds modulate immune function by reducing inflammation, with early clinical evidence for MS, IBD, and fibromyalgia and preclinical promise for rheumatoid arthritis and type 1 diabetes.
2017 / Narrative Review / Moderate evidencePhysician-focused primer reviewing cannabis compounds for pain and headaches, covering FDA-approved synthetic cannabinoids, phytocannabinoids, and the emerging role of terpenes and flavonoids.
2017 / Animal Study / Preliminary evidenceRat study showing a dual FAAH inhibitor/TRPV1 blocker produced antidepressant effects at a specific dose by enhancing anandamide signaling through CB1 receptors while blocking the opposing TRPV1 pathway.
2017 / Animal Study / Preliminary evidenceFirst study identifying GPR3 and GPR6 as novel molecular targets for CBD, with potential implications for Alzheimer's and Parkinson's disease treatment through mechanisms distinct from classical cannabinoid receptors.
2017 / Narrative Review / Moderate evidenceReview showing cannabinoids provide established palliative benefits for brain tumor patients (pain, nausea, anxiety) and demonstrated 50-95% tumor regression in animal glioma studies, with synergistic effects in combination therapies.
2017 / Review / Strong evidenceComprehensive review of how endocannabinoids modulate anxiety through multiple brain regions, receptors, and mechanisms, explaining why cannabis can both reduce and increase anxiety depending on context.
2017 / Meta Analysis / Strong evidenceMeta-analysis of 11 RCTs finding selective cannabinoids provide a small but significant reduction in neuropathic pain (-0.65 on 0-10 scale), with improvements in sleep and quality of life.
2017 / Animal Study / Preliminary evidenceMouse study showing CBD prevented cognitive and emotional deficits after brain ischemia by reducing inflammation, preventing neuron death, increasing BDNF, and stimulating new brain cell growth.
2017 / Animal Study / Preliminary evidenceRat study showing AA-5-HT (dual FAAH/TRPV1 blocker) promoted sleep during active periods, restored sleep after deprivation, and blocked the wake-promoting effects of CBD and modafinil.
2017 / Randomized Controlled Trial / Moderate evidenceSmall RCT of 20 Crohn's patients finding CBD 10 mg twice daily was safe but no more effective than placebo, possibly due to insufficient dosing.
2017 / Review / Strong evidenceReview of CBD for treatment-resistant epilepsy showing Phase 3 RCT evidence of efficacy for Dravet and Lennox-Gastaut syndromes, while highlighting the gap between pharmaceutical CBD and unvalidated dispensary products.
2017 / Review / Moderate evidenceReview of how the endocannabinoid system controls immunity, finding widespread expression in immune cells with generally immunosuppressive effects that create both therapeutic opportunities and safety considerations.
2017 / Animal Study / Preliminary evidenceMouse study found that endocannabinoid levels in the uterus fluctuate across the reproductive cycle, and cannabinoid receptor activation selectively reduces spontaneous uterine contractions.
2017 / Observational / Preliminary evidenceSmall observational study found CBD-rich hemp oil improved physical functioning, vitality, and pain in young women with chronic symptoms after HPV vaccination, though one-third of participants dropped out.
2017 / Review / Moderate evidenceReview examining arguments for (pressure reduction, neuroprotection) and against (short duration, side effects, delivery challenges) using cannabinoids to treat glaucoma.
2017 / Review / Strong evidenceReview marking a turning point: three controlled trials confirmed CBD reduces seizures in Dravet and Lennox-Gastaut syndromes, but a drug interaction with clobazam complicates interpretation of how much benefit is directly from CBD.
2017 / Animal Study / Preliminary evidenceRat study found that locally administered CBD reduced osteoarthritis pain and, when given early, prevented pain development and protected joint nerves from damage.
2017 / Review / Strong evidenceComprehensive review finding that CBD and CBDV consistently reduce seizures in animal models, while THC-like CB1 agonists show complex, context-dependent effects that can be either anti- or pro-seizure.
2017 / Animal Study / Preliminary evidenceRat study found CBD disrupted fear memory consolidation when injected into the prefrontal cortex 5 hours (but not immediately) after fear learning, reducing dopamine activity and memory gene expression.
2017 / Review / Strong evidenceMajor pharmacology review arguing that cannabis's therapeutic potential involves far more than THC and CBD, with terpenes and lesser-known compounds providing meaningful synergistic pharmacological activity.
2017 / Qualitative / Preliminary evidenceQualitative study of 25 parents using cannabis for pediatric epilepsy found they viewed themselves as scientific experimenters who wanted biomedical legitimacy, not alternative medicine rebels.
2017 / Narrative Review / Preliminary evidenceThe biology linking the endocannabinoid system to PTSD was strong, but clinical evidence for cannabis as treatment was weak. Nabilone showed real promise for nightmares specifically.
2017 / Animal Study / Preliminary evidenceRat study showing CBD disrupted both specific and generalized fear memory consolidation through anandamide-mediated CB1 and CB2 receptor activation in the dorsal hippocampus.
2017 / Prospective Cohort / Moderate evidenceControlled study found smoked/vaporized cannabis produced higher peak THC in saliva, while edibles created wider metabolite detection windows, with minor cannabinoids showing promise as markers of recent use.
2017 / Animal Study / Preliminary evidenceMouse study found CBD modestly reduced some THC behavioral effects but their combination produced unexpected epigenetic changes in the brain's reward pathway not seen with either compound alone.
2017 / Retrospective Cohort / Moderate evidenceChart review of 119 pediatric epilepsy patients found 71% discontinued cannabis extracts, with only 13% achieving greater than 50% seizure reduction and perceived benefit the sole predictor of continued use.
2017 / Animal Study / Preliminary evidenceMouse study of Huntington's disease found a Sativex-like THC+CBD combination reduced dystonia and partially reversed metabolic brain changes, though motor coordination did not improve.
2017 / Review / Moderate evidenceReview of cannabis legalization's unintended pediatric consequences, covering prenatal exposure, accidental childhood ingestion, adolescent use, and the need for rigorous CBD epilepsy trials.
2017 / Observational / Preliminary evidenceLab testing found consumer hemp seeds contained up to 1,250% more THC than Canada's legal limit, with potential for 3.8 mg THC exposure from a daily serving.
2017 / Animal Study / Preliminary evidenceTaking cannabinoids with fats boosted CBD levels in the lymphatic system 250-fold above blood levels, reaching concentrations that suppressed immune cell activity, especially in MS patients.
2018 / Animal Study / Preliminary evidenceThree cannabinoid compounds reduced inflammatory markers IL-6 and MCP-1 in human periodontal cells, suggesting potential for cannabinoid-based gum disease treatments.
2018 / Animal Study / Preliminary evidenceZebrafish larvae metabolized THC and CBD similarly to mammals, with each producing distinct behavioral patterns and their combination altering both absorption and behavior.
2018 / Randomized Controlled Trial / Preliminary evidenceNew oral CBD formulation (PTL101) delivered 34% more CBD into the bloodstream than Sativex spray, with safe and efficient delivery in healthy volunteers.
2018 / Review / Moderate evidenceComprehensive review catalogues medicinal properties of individual cannabinoids, terpenes, and flavonoids, explaining the entourage effect and building the case for strain-specific cannabis medicine.
2018 / Observational / Moderate evidenceProfiling 94 phytocannabinoids across 36 strains showed that high-CBD extracts with equal CBD content produced different anticonvulsant effects, proving THC/CBD ratios alone are insufficient.
2018 / Review / Strong evidenceConference report documents FDA approval of CBD oral solution for Lennox-Gastaut and Dravet syndromes, the first cannabis-derived FDA-approved medication.
2018 / Review / Moderate evidenceCommentary examines two cannabinoid drug development paths: whole-plant extracts offering entourage effects versus single-molecule drugs offering precision, with legalization complicating both.
2018 / Review / Moderate evidenceReview confirms CBD efficacy for Dravet and Lennox-Gastaut syndromes but highlights practical challenges including drug interactions, variable absorption, and unclear mechanisms.
2018 / Review / Moderate evidenceVeterinary review documents rising pet exposures to marijuana, CBD, and synthetic cannabinoids, with dogs especially sensitive to THC due to higher cerebellar CB1 receptor density.
2018 / Animal Study / Preliminary evidenceMale mice given daily CBD for 34 days showed 76% testosterone reduction, 38% fewer sperm, and sperm abnormalities persisting after a 35-day recovery period.
2018 / Review / Moderate evidenceReview found no increase in accidents from Sativex spray in MS patients, with most reporting improved driving after treatment, though blood THC may exceed legal limits in some countries.
2018 / Case Report / Preliminary evidenceThree patients with the rare blistering condition epidermolysis bullosa reported faster wound healing, less blistering, and pain relief from topical CBD, with one stopping opioids completely.
2018 / Review / Moderate evidenceTranslational review of CBD research identifies established anxiolytic, antipsychotic, and neuroprotective properties with emerging evidence across epilepsy, PTSD, depression, and other conditions.
2018 / Animal Study / Preliminary evidenceCBD rescued mitochondrial damage from iron accumulation in rat brains, restoring ferritin levels, epigenetic regulation, and enzyme activity, supporting its neuroprotective potential.
2018 / Review / Strong evidenceComprehensive review cataloged six approved cannabinoid medications and evidence across pain, epilepsy, cancer, neurodegeneration, PTSD, anxiety, and addiction, spanning the full endocannabinoid system.
2018 / Randomized Controlled Trial / Moderate evidenceCrossover fMRI study found cannabis dampened the brain's reward response to music in the ventral striatum and other regions, but CBD restored normal connectivity and responses.
2018 / Review / Strong evidenceReview documents FDA-approved purified CBD (Epidiolex) significantly reducing seizures in Dravet and Lennox-Gastaut syndromes, with key drug interactions identified for clobazam and valproate.
2018 / Randomized Controlled Trial / Preliminary evidenceCrossover fMRI study found 600mg CBD enhanced fronto-striatal brain connectivity in 16 healthy males, offering a potential neural mechanism for its antipsychotic properties.
2018 / Review / Moderate evidenceReview proposed CBD as treatment for cannabis users with early psychosis, based on evidence of antipsychotic properties and ability to counteract THC's psychotogenic, anxiogenic, and cognitive effects.
2018 / Observational / Moderate evidenceObservational study found 56% of children with treatment-resistant epilepsy achieved 50%+ seizure reduction with CBD-enriched cannabis oil (20:1 ratio), with younger age and higher doses predicting better response.
2018 / Cross Sectional / Preliminary evidenceChemical analysis of strains rated most and least effective for anxiety found THC and the terpene trans-nerolidol correlated with anxiety relief, while six other terpenes correlated with reduced effectiveness.
2018 / Review / Moderate evidenceNature Reviews Rheumatology review found emerging evidence for cannabinoid immunomodulatory effects relevant to rheumatic diseases, but concluded evidence is insufficient to recommend cannabis treatment for these conditions.
2018 / Meta Analysis / Strong evidenceMeta-analysis of 550 patients found CBD reduced seizures by ~20 percentage points in severe childhood epilepsies. The lower dose (10 mg/kg) was similarly effective but safer than the higher dose (20 mg/kg).
2018 / Pilot Study / Preliminary evidencePilot study of 25 children with complex motor disorders found CBD-enriched cannabis oil improved spasticity, dystonia, sleep, pain, and quality of life over 5 months, with rare adverse effects.
2018 / Animal Study / Moderate evidenceCB2 agonist LY2828360 suppressed neuropathic pain without tolerance in mice, prevented morphine tolerance, and worked even in morphine-tolerant animals. Its G protein-biased signaling may explain the sustained efficacy.
2018 / Review / Moderate evidencePractical dosing review recommended medical cannabis THC be limited to 30 mg/day, combined with CBD, started low and titrated slowly over two weeks, with guidance for special populations and drug interactions.
2018 / Review / Moderate evidenceCritical review found CBD shows distinct promise for psychosis, anxiety, and withdrawal symptoms, each through different pharmacological mechanisms, but needs larger controlled trials.
2018 / Pilot Study / Moderate evidenceOpen-label trial of 20 Dravet syndrome children found CBD/THC cannabis oil achieved 70.6% median seizure reduction and 63% responder rate, with significant quality of life improvement over 20 weeks.
2018 / Animal Study / Moderate evidenceTHC lowered mouse eye pressure by 28% via CB1 and GPR18 receptors, with stronger effects in males. CBD had opposing effects on eye pressure and blocked THC's beneficial IOP reduction.
2018 / Randomized Controlled Trial / Strong evidenceRandomized crossover trial found vaporized CBD at 2:1 ratio did not block THC-induced psychotic symptoms or memory impairment. CBD alone helped only light users, not frequent users.
2018 / Systematic Review / Strong evidenceCochrane review of 16 trials (1,750 patients) found cannabis-based medicines provide modest neuropathic pain relief (NNT 20 for 50% relief) with significant side effects (61% nervous system AEs, 17% psychiatric AEs). Harms may outweigh benefits.
2018 / Systematic Review / Strong evidenceReview of 11 systematic reviews found cannabinoids may have modest benefits for MS pain and spasticity, but evidence for other symptoms is insufficient and no studies compare cannabinoids to existing treatments.
2018 / Meta Analysis / Moderate evidenceMeta-analysis of 670 epilepsy patients found CBD-rich whole-plant extracts outperformed purified CBD (71% vs 46% improvement) at lower doses (6 vs 25 mg/kg/day) with fewer side effects, supporting the entourage effect.
2018 / Retrospective Cohort / Moderate evidenceRetrospective study of 108 children found artisanal CBD oil achieved >50% seizure reduction in 39%, with 10% seizure-free, 14% showing improved alertness, and minimal side effects.
2018 / Review / Moderate evidenceReview argues cannabis compounds (THC, CBD, THCA, CBDA, terpenes) show promise for five currently hard-to-treat neurological conditions including Parkinson, Alzheimer, and brain tumors.
2018 / Review / Moderate evidenceCBD has proven benefit for Dravet and Lennox-Gastaut syndromes, and three other cannabinoids (CBDV, THCV, THCA) are in the epilepsy research pipeline.
2018 / Review / Strong evidenceReview traces the journey from anecdotal evidence to FDA approval of purified CBD (Epidiolex) for two severe childhood epilepsy syndromes, affecting the roughly one-third of epilepsy patients who are drug-resistant.
2018 / Case Report / Preliminary evidenceCase series found that substituting street cannabis with a low-THC medicinal cannabis variant was not effective for treating cannabis use disorder in seven psychosis inpatients.
2018 / Randomized Controlled Trial / Strong evidenceRigorous abuse potential study found CBD showed very low drug-liking even at 6 times the therapeutic dose, and it was significantly lower than alprazolam and dronabinol on all abuse measures.
2018 / Review / Moderate evidenceReview highlights that while CBD treats childhood epilepsy effectively, the endocannabinoid system plays critical roles in brain development, and long-term effects of modulating it in children remain unknown.
2018 / Systematic Review / Strong evidenceSystematic review of 36 studies confirmed CBD reduces seizures in treatment-resistant epilepsy (NNT=8 for 50% reduction), with 8.5% achieving complete seizure freedom, though serious adverse events increased.
2018 / Cross Sectional / Preliminary evidenceChemical analysis of cannabis extracts used by 41 Australian families for childhood epilepsy found wildly inconsistent cannabinoid content, with most samples low in CBD and high in THC, contrary to parents' beliefs.
2018 / Randomized Controlled Trial / Preliminary evidencePilot trial found nabiximols was safe and well-tolerated in cannabis-dependent patients, with 70.5% cannabis use reduction (vs 42.6% placebo) and reduced craving, though differences were not statistically significant.
2019 / Review / Preliminary evidenceA review of cannabis evidence for autism found only five small studies and mixed results for all conditions except epilepsy, highlighting a major gap between anecdotal reports and scientific evidence.
2019 / Animal Study / Preliminary evidenceIn a mouse MS model, THC plus CBD together (but not alone) reduced paralysis and brain inflammation by suppressing inflammatory immune cells and altering microRNA gene regulation.
2019 / Animal Study / Preliminary evidenceTHC+CBD reduced MS-like symptoms in mice partly by reshaping gut bacteria, as confirmed by fecal transplant experiments showing the microbiome changes were causally involved in the therapeutic effect.
2019 / Animal Study / Preliminary evidenceCBD helped zebra finches recover their learned songs faster after targeted brain lesions, with higher doses reducing both the severity and duration of vocal impairment.
2019 / Review / Strong evidenceThree randomized controlled trials showed CBD reduced seizures by 38-41% in severe childhood epilepsies, performing comparably to established anti-epileptic drugs with manageable side effects.
2019 / Animal Study / Preliminary evidenceBeta-caryophyllene, a non-psychoactive cannabis compound, prevented and reduced HIV drug-induced nerve pain in mice by activating CB2 receptors and reducing inflammatory cytokines.
2019 / Review / Moderate evidenceDespite strong evidence that cannabinoids improve colitis in animal models, clinical trials in human IBD have not shown meaningful benefit, with THC tolerance limiting the largest study.
2019 / Animal Study / Moderate evidenceCBD and clobazam work better together through two mechanisms: CBD raises clobazam blood levels AND both drugs together directly enhance GABA receptor inhibition, providing genuine therapeutic synergy.
2019 / Retrospective Cohort / Preliminary evidenceIn 60 children with autism and severe behavioral problems, CBD-rich cannabis improved behavioral outbreaks in 61% with mostly mild side effects, supporting feasibility of controlled trials.
2019 / Randomized Controlled Trial / Moderate evidenceA controlled trial found cannabis with equal CBD and THC impaired driving and cognition as much as THC-only cannabis, with CBD actually worsening some cognitive tasks, possibly by increasing THC blood levels.
2019 / Cross Sectional / Moderate evidenceIn a survey of 484 women with endometriosis, cannabis was rated the most effective self-management strategy for pain (7.6/10), ahead of heat, CBD oil, and dietary changes.
2019 / Prospective Cohort / Moderate evidenceIn a prospective study of 188 autism patients treated with CBD-rich cannabis oil for six months, 84% of those assessed reported improvement, with mostly mild side effects and high treatment continuation.
2019 / Systematic Review / Preliminary evidenceA systematic review found CBD improved schizophrenia symptoms (especially early-stage) and reduced cannabis withdrawal when combined with THC, with blood anandamide levels as a potential biomarker.
2019 / Animal Study / Preliminary evidenceBeta-caryophyllene, a cannabis compound with GRAS safety status, reduced bladder inflammation and pain in mice better than the FDA-approved treatment DMSO through CB2 receptor activation.
2019 / Review / Strong evidenceEpidiolex became the first CBD medication approved by a national regulator, earning FDA approval for Dravet and Lennox-Gastaut syndromes based on Phase III clinical trials.
2019 / Meta Analysis / Strong evidenceA Lancet meta-analysis of 83 studies found scarce evidence that cannabinoids help depression, anxiety, PTSD, or other mental disorders, with THC products doubling adverse event rates versus placebo.
2019 / Systematic Review / Preliminary evidenceA systematic review of 1,301 papers found only 27 qualifying studies of CBD for psychiatric disorders, with limited but promising signals for substance use, psychosis, and anxiety.
2019 / Review / Preliminary evidenceA review found CBD reversed stimulant toxicity, reduced drug-seeking, and prevented relapse in animal models of cocaine and methamphetamine addiction, with observational human data showing reduced craving.
2019 / Review / Moderate evidenceA review found CBD shows therapeutic potential across autism, anxiety, psychosis, pain, epilepsy, and neurodegenerative diseases, with mainly diarrhea and somnolence as side effects.
2019 / Review / Strong evidenceEpidiolex (pure CBD) reduced severe seizures by 17-23% over placebo in children with Dravet and Lennox-Gastaut syndromes, with key drug interactions requiring careful management.
2019 / Review / Preliminary evidenceA review found growing evidence for cannabis-based treatments in CDKL5 Deficiency Disorder, including an open-label trial showing seizure reduction, building on proven CBD efficacy in similar severe epilepsies.
2019 / Review / Moderate evidenceReview of evidence suggesting CBD has antipsychotic properties through a unique non-dopamine mechanism, potentially offering a new treatment class for psychotic disorders with fewer side effects.
2019 / Narrative Review / Preliminary evidenceNarrative review of animal studies showing CBD reduces alcohol consumption, motivation to drink, and relapse while protecting against alcohol-related liver and brain damage.
2019 / Systematic Review / Strong evidenceSystematic review of 23 studies finds moderate-certainty evidence that pharmaceutical CBD reduces seizure frequency by about 20% in children with drug-resistant epilepsy, with diarrhea as the main side effect.
2019 / Narrative Review / Moderate evidenceComprehensive review finding CBD has established efficacy for epilepsy, early clinical signals for anxiety and psychosis, and preclinical-only evidence for depression and Alzheimer's.
2019 / Observational / Preliminary evidenceObservational study of 18 autism patients found CBD-rich cannabis extract (75:1 CBD:THC) improved symptoms in 14 of 15 who completed 6-9 months of treatment, with strongest gains in seizures, ADHD, sleep, and social interaction.
2019 / Review / Strong evidenceComprehensive review of FDA-approved CBD for epilepsy details its efficacy in severe childhood epilepsies, complex pharmacokinetics including a 4x food effect, and important drug interaction with clobazam that may partly explain its benefits.
2019 / Review / Moderate evidenceReview of cannabinoid-based addiction treatments finds promising newer strategies including neutral CB1 antagonists, CB2 agonists, and CBD after the rimonabant setback, with some entering clinical trials.
2019 / Animal Study / Preliminary evidenceLab and mouse study shows CBD, CBN, and THC all suppress immune defenses against three major gum disease bacteria through a CB2/PI3K pathway, revealing why cannabis use increases periodontal disease risk.
2019 / Review / Preliminary evidenceReview finds cannabis shows anti-inflammatory potential for IBD, but evidence is insufficient to recommend use in pediatric patients, calling for pediatric-specific safety and efficacy studies.
2019 / Case Report / Preliminary evidenceCase report of CBD use for chronic pain and mood disorder in neurofibromatosis type 1, suggesting potential but requiring controlled trials for validation.
2019 / Observational / Preliminary evidenceStudy of young IBD patients found 15 cannabis oil users had similar clinical profiles to 67 non-users but reported perceived benefits for sleep, nausea, and appetite, with most also using other cannabis forms.
2019 / Animal Study / Preliminary evidenceRat study identifies ERK1-2 phosphorylation in the hippocampus as the molecular mechanism by which THC causes psychosis-like dopamine dysregulation and CBD reverses it.
2019 / Animal Study / Preliminary evidenceRat study shows CBD reduces diabetic nerve pain through spinal cord serotonin 5-HT1A receptors rather than cannabinoid receptors, with chronic treatment restoring depleted serotonin levels.
2019 / Cross Sectional / Preliminary evidenceOregon survey of 39 cannabis-using epilepsy patients found 87% used for seizures and 82% said it helped, but only 2 could specify their dose, highlighting the gap between self-medication and medical-grade use.
2019 / Systematic Review / Moderate evidenceSystematic review of CBD in psychiatry finds limited evidence for cannabis withdrawal, addiction, psychosis, and social anxiety, with few side effects.
2019 / Animal Study / Preliminary evidenceCannabinoids reduced GVHD and improved survival in transplanted mice but also slowed immune cell recovery, highlighting a complex therapeutic tradeoff.
2019 / Review / Moderate evidenceComprehensive review of CBD's anti-cancer properties, documenting multiple mechanisms of action from lab studies to early clinical evidence.
2019 / Randomized Controlled Trial / Moderate evidenceRCT in 16 volunteers found a self-emulsifying CBD formulation achieved 4.4x higher peak levels and 3x greater absorption than standard CBD oil.
2019 / Observational / Preliminary evidenceProspective study found only 24% of children with refractory epilepsy responded to artisanal cannabis extracts, matching placebo rates from pharmaceutical CBD trials.
2019 / Review / Strong evidenceReview examines CBD as the first new class of antiepileptic drugs, with clinical evidence supporting its use as adjunctive treatment for Lennox-Gastaut and Dravet syndromes.
2019 / Observational / Strong evidenceExpanded access program showed add-on CBD reduced major motor seizures by 50% at 12 weeks, sustained through 96 weeks, in patients with LGS or Dravet syndrome.
2019 / Cross Sectional / Moderate evidenceSurvey finds dispensaries in three countries advertise cannabis for at least 12 skin conditions, with most claims lacking clinical evidence.
2019 / Review / Strong evidenceReview of animal and human studies finds cannabinoid-facilitated extinction of traumatic memories with large effect sizes, acting through prefrontal cortex, amygdala, and hippocampus.
2019 / Animal Study / Preliminary evidenceBoth a standardized cannabis extract and pure CBD inhibited human immune cell functions, but the extract was more potent for cell migration and TNF-alpha production.
2019 / Review / Strong evidencePost-approval trials confirm THC:CBD spray (Sativex) effectively treats resistant MS spasticity without cognitive or mood side effects through 50 weeks.
2019 / Randomized Controlled Trial / Strong evidenceSAVANT RCT found 77% of MS patients on add-on Sativex achieved meaningful spasticity improvement vs 32% on optimized standard treatment (p<0.0001).
2019 / Systematic Review / Strong evidenceSystematic review of 35 CBD clinical studies finds effective doses from 1-50 mg/kg/day across 13 conditions, with epilepsy best supported and negative results potentially due to underdosing.
2019 / Pilot Study / Preliminary evidencePhase II trial of CBD gelatin bead formulation (PTL-101) showed 82% seizure reduction in children with treatment-resistant epilepsy, with 56% achieving 50%+ improvement.
2019 / Review / Moderate evidenceReview of cannabinoid-AED interactions shows enhanced seizure protection but also neurotoxicity with non-selective agonists; selective CB1 agonists may offer safer combinations.
2019 / Randomized Controlled Trial / Strong evidencePhase 1 trial shows CBD triples active clobazam metabolite levels, modestly increases stiripentol, and does not affect valproate, guiding dose adjustments for combination therapy.
2019 / Review / Moderate evidenceReview of cannabinoids for chemotherapy nausea highlights CBD's non-psychoactive antiemetic potential through serotonin inhibition, alongside THC's established efficacy.
2019 / Animal Study / Moderate evidenceMouse study found CBD did not prevent THC cognitive impairment or withdrawal, but CBD alone showed anxiolytic effects without cognitive harm or dependence.
2019 / Animal Study / Preliminary evidenceCBD reversed memory and social deficits in female rats from a schizophrenia model, but reduced social behavior in healthy rats.
2019 / Review / Moderate evidenceCannabis shows promise in animal IBD models but has not demonstrated anti-inflammatory efficacy in human trials. It may help manage symptoms like pain and nausea.
2019 / Case Report / Preliminary evidenceA patient with Tourette syndrome resistant to antipsychotics and pure THC showed rapid improvement when treated with a THC + CBD combination.
2019 / Pilot Study / Preliminary evidenceIn 29 children with severe epilepsy, purified CBD reduced seizures by 50% or more in 38% of patients, with mild side effects and no worsening in any patient.
2019 / Review / Preliminary evidenceCBD is theoretically promising for autism spectrum disorder, but at the time of this review, no convincing evidence of efficacy or safety in ASD patients existed.
2019 / Randomized Controlled Trial / Moderate evidenceA single dose of CBD altered brain activity in regions implicated in autism (cerebellum, fusiform gyrus) in men with ASD but not in neurotypical controls.
2019 / Randomized Controlled Trial / Moderate evidenceCBD modulated brain glutamate and GABA levels, but in opposite directions for people with autism versus neurotypical controls.
2019 / Systematic Review / Moderate evidenceCannabis components inhibit multiple liver enzymes responsible for metabolizing common medications, creating potential for significant drug interactions.
2019 / Review / Moderate evidenceCBD is FDA-approved for two childhood epilepsies but has significant drug interactions, liver risks with valproate, and regulatory challenges that affect patient access.
2019 / Prospective Cohort / Moderate evidenceOver four years, CBD helped 27% of children with severe epilepsy (3 became seizure-free), but 81% had side effects and most discontinued.
2019 / Animal Study / Preliminary evidenceCBD improved memory and reduced brain inflammation in diabetic middle-aged rats with impaired cerebral blood flow, through anti-inflammatory rather than neuroplasticity mechanisms.
2019 / Animal Study / Preliminary evidenceNine of 11 cannabinoids protected neurons in an Alzheimer's drug screening model, removed amyloid, and worked through both receptor-dependent and independent mechanisms.
2019 / Randomized Controlled Trial / Strong evidenceA controlled trial found low-dose CBD enhanced THC intoxication while high-dose CBD reduced it, with the strongest effects in infrequent cannabis users.
2019 / Animal Study / Preliminary evidenceCBD given during adolescence prevented schizophrenia-like symptoms and normalized cannabinoid receptor changes in a rat model, while haloperidol did not.
2019 / Randomized Controlled Trial / Moderate evidenceRigorous crossover trial in 20 fibromyalgia patients found single cannabis inhalation had limited pain effects, with a surprising finding that CBD reduced THC's analgesic benefit.
2019 / Animal Study / Preliminary evidenceComprehensive mouse behavioral testing found CBD produced no rewarding effects, no withdrawal, and no self-administration motivation, supporting its lack of abuse potential.
2019 / Randomized Controlled Trial / Moderate evidenceBrain imaging study found THC disrupted key brain networks, with feeling "stoned" linked to disruption of the posterior cingulate cortex, while CBD restored salience network changes.
2019 / Review / Moderate evidenceReview of CBD evidence found strong support only for seizures, with promising but unproven data for anxiety and schizophrenia, and weak evidence for most marketed uses.
2020 / Review / Strong evidenceReview of FDA-approved Epidiolex for childhood epilepsy details its seizure-reducing benefits alongside important drug interactions with clobazam and valproate.
2020 / Review / Moderate evidenceReview of non-THC cannabinoids in cancer finds preclinical evidence of anti-tumor effects through multiple mechanisms, but no clinical confirmation yet.
2020 / Review / Strong evidenceCBD is mostly well-tolerated but can cause life-threatening reactions when combined with valproate or clobazam, commonly used in epilepsy patients who take CBD.
2020 / Observational / Preliminary evidenceEEG brain network analysis distinguished CBD responders from non-responders in refractory epilepsy, with key differences in the beta frequency band.
2020 / Animal Study / Preliminary evidenceIn Dravet mice, acute low-dose THC plus CBD was anticonvulsant, but chronic combination unexpectedly increased seizure severity and mortality.
2020 / Randomized Controlled Trial / Strong evidenceJAMA trial with actual on-road driving found THC impaired lane-keeping for up to 100 minutes but not at 4 hours, while CBD had no measurable effect.
2020 / Animal Study / Preliminary evidenceMouse study found CBD reduced conditioned fear while CBDA reduced generalized anxiety after trauma, suggesting complementary therapeutic roles.
2020 / Case Report / Preliminary evidenceA man developed respiratory depression and bradycardia after gas station CBD gummies, highlighting the dangers of unregulated CBD products.
2020 / Systematic Review / Moderate evidenceSystematic review of 17 neuroimaging studies found CBD consistently modulated brain activity in regions relevant to psychosis and anxiety, often opposite to THC effects.
2020 / Systematic Review / Moderate evidenceReview of cannabis for fibromyalgia finds patient surveys suggest significant benefit, but randomized trial evidence remains limited and questioned.
2020 / Observational / Moderate evidenceSimulations suggest CBD's seizure reduction in Lennox-Gastaut syndrome may be explained by its interaction with clobazam rather than direct anti-seizure effects.
2020 / Meta Analysis / Strong evidenceMeta-analysis of pivotal trials found CBD has independent anti-seizure effects, though the benefit is amplified by interaction with clobazam.
2020 / Randomized Controlled Trial / Preliminary evidenceA small crossover trial found that 600mg of CBD increased blood flow to the hippocampus by an average of 15 mL/100g/min, with increased orbitofrontal blood flow correlating with faster working memory reaction times.
2020 / Narrative Review / Preliminary evidenceTHC interacts with common medications through shared liver enzymes (CYP3A4, CYP2C9), and genetic variants in up to 35% of Caucasians increase THC bioavailability.
2020 / Systematic Review / Preliminary evidenceA critical review of five studies (827 participants) found cannabinoid treatments showed promise for fibromyalgia pain, but significant methodological limitations in the research prevent definitive conclusions about efficacy.
2020 / Prospective Cohort / Moderate evidenceA prospective study of 49 children with drug-resistant epilepsy in Argentina found 80% responded to add-on CBD therapy, with a median 66% seizure reduction and mild side effects.
2020 / Animal Study / Preliminary evidenceA synthetic cannabinoid that blocks CB1 and activates CB2 receptors reduced brain injury and white matter damage in newborn rats even when given 3 hours after oxygen deprivation.
2020 / Review / Preliminary evidenceA review found cannabis associated with improved IBD symptom scores and quality of life, but the lack of standardized preparations, doses, and routes of administration prevents establishing treatment guidelines.
2020 / Review / Preliminary evidenceA review found suggestive evidence that CBD may reduce anxiety and fear responses in PTSD, but cannabis use may worsen depression. Well-designed randomized trials remain largely absent across these conditions.
2020 / Animal Study / Preliminary evidenceCBD reversed the increased pain sensitivity in a mouse model of Parkinson's disease, with effects mediated through CB1 receptors and potentially by increasing endogenous anandamide levels.
2020 / Review / Moderate evidenceA review found purified CBD shows modest but significant seizure improvement in severe epilepsy, but important drug interactions, a 1-in-23 serious adverse event risk, and a wide gap between evidence and public belief complicate clinical use.
2020 / Prospective Cohort / Moderate evidenceA multicenter study of 125 children found slow CBD titration achieved 38% with 50%+ seizure reduction at 6 months with better tolerability than previous faster protocols. Clobazam did not add efficacy but increased some side effects.
2020 / Review / Moderate evidenceA review found CBD acts on diverse molecular targets including serotonin 5-HT1A receptors, TRPV1 channels, and cannabinoid receptors, explaining its broad therapeutic profile across anxiety, pain, and epilepsy.
2020 / Meta Analysis / Strong evidenceA meta-analysis of 4 RCTs confirmed CBD significantly reduces seizures both with and without clobazam, though the effect was somewhat larger with clobazam. Side effects like somnolence were increased with the combination.
2020 / Review / Moderate evidenceA leading endocannabinoid researcher describes the expanded endocannabinoidome as a platform for non-psychoactive cannabinoid therapies and highlights its connection to the gut-brain axis in neuropsychiatric disorders.
2020 / Systematic Review / Strong evidenceSystematic review of 35 studies found cannabidiol likely reduces seizure frequency in children with drug-resistant epilepsy, though it did not achieve seizure freedom more than placebo and increased GI side effects.
2020 / Animal Study / Preliminary evidenceCell study found five cannabinoid agents protected rat brain cells from combined high glucose and amyloid beta damage, with the FAAH inhibitor URB597 showing the strongest neuroprotection.
2020 / Review / Preliminary evidenceReview examines the theoretical basis for combining cannabis terpenes with cannabinoids to treat mood and anxiety disorders, finding preclinical support but limited clinical evidence.
2020 / Observational / Moderate evidenceLab study found five common cannabis terpenes had no detectable activity at CB1 or CB2 receptors and did not modify THC, CBD, or endocannabinoid binding or function.
2020 / Randomized Controlled Trial / Strong evidenceFirst RCT of CBD for cannabis use disorder found 400mg and 800mg daily were safe and more effective than placebo at reducing cannabis use over 4 weeks, with 94% completing treatment.
2020 / Systematic Review / Moderate evidenceSystematic review of 10 studies found cannabinoids may improve behavioral symptoms, sleep, and hyperactivity in autism, while reducing seizures in those with comorbid epilepsy, though evidence on core ASD symptoms is limited.
2020 / Animal Study / Preliminary evidenceRat study found CBD reduced cocaine self-administration and reward by attenuating dopamine release in the nucleus accumbens, working through CB2, serotonin 5-HT1A, and TRPV1 receptors.
2020 / Systematic Review / Moderate evidenceSystematic review of 8 studies with 210 participants found limited evidence for CBD as an antipsychotic but noted its favorable side effect profile compared to standard medications.
2020 / Pilot Study / Preliminary evidencePilot study of 10 young epilepsy patients found a THC/CBD cannabis preparation was generally safe, with blood levels correlating to dose, supporting the feasibility of therapeutic drug monitoring.
2020 / Animal Study / Moderate evidenceMouse study found CBD's anti-seizure effects were abolished in mice lacking the TRPV1 receptor, strongly implicating this receptor in CBD's mechanism of action against seizures.
2020 / Randomized Controlled Trial / Strong evidencePhase II crossover trial found oral THC:CBD capsules nearly doubled complete response for refractory chemo nausea (25% vs 14%), with 83% of patients preferring cannabis to placebo despite more side effects.
2020 / Meta Analysis / Strong evidenceMeta-analysis of 15 controlled studies confirms THC induces psychotic, negative, and general psychiatric symptoms with large effect sizes in healthy people, while CBD shows no consistent protective effect.
2020 / Randomized Controlled Trial / Moderate evidenceCrossover study of 12 volunteers found oral CBD absorbed much better in oil or nano-emulsion than powder, with nano-emulsion providing the most consistent absorption profile.
2020 / Review / Moderate evidenceCritical review found moderate evidence for THC:CBD spray (Sativex) reducing MS spasticity and pain, but limited evidence for other MS symptoms.
2020 / Randomized Controlled Trial / Preliminary evidenceSmall RCT with 14 OCD patients found no significant symptom reduction from acute smoked cannabis (THC or CBD) versus placebo, though CBD showed a trend toward reduced anxiety.
2020 / Systematic Review / Moderate evidenceSystematic review of 23 studies found CBD most promising for anxiety and as adjunct treatment for psychosis, with limited evidence for depression and PTSD.
2020 / Retrospective Cohort / Moderate evidenceFirst Korean study of CBD for childhood epilepsy found about one-third of Lennox-Gastaut and Dravet syndrome patients achieved 50%+ seizure reduction at 3 months, with mostly mild side effects.
2020 / Review / Preliminary evidenceReview found early evidence that medical cannabis may help behavioral symptoms in children with autism or fetal alcohol spectrum disorder, and severe nausea in pregnancy, but data remain very limited.
2020 / Observational / Preliminary evidenceMouse study found CBD extract significantly induced liver enzymes but the supplement MSM didn't amplify the effect or cause additional toxicity.
2020 / Systematic Review / Moderate evidenceSystematic review of 25 CBD studies (927 patients) found the best evidence for anxiety and psychosis, with wide dosing variation and generally mild side effects.
2020 / Meta Analysis / Strong evidenceMeta-analysis of 3 RCTs (359 patients) found CBD increased 50% seizure reduction by 69% in Dravet syndrome, with notable side effects including somnolence and liver enzyme changes.
2020 / Meta Analysis / Strong evidenceMeta-analysis of 4 RCTs (714 patients) showed CBD reduced seizures in Dravet and Lennox-Gastaut syndrome regardless of whether patients were also taking clobazam.
2020 / Randomized Controlled Trial / Preliminary evidenceDouble-blind fMRI study found a single 600mg CBD dose did not alter reward-related brain activity or motivation in 23 healthy volunteers.
2020 / Pilot Study / Preliminary evidenceOpen-label study of 13 Parkinson patients found high-dose CBD improved motor scores by 25% but caused liver enzyme elevations in 38.5% and 85% had diarrhea.
2020 / Randomized Controlled Trial / Moderate evidenceRandomized crossover study found co-inhaled high-dose CBD significantly reduced THC systemic availability, with frequent users showing higher levels of both compounds.
2020 / Randomized Controlled Trial / Moderate evidenceSix-week RCT of 65 overweight adults found 15mg daily CBD hemp extract significantly improved HDL cholesterol, with trends toward better sleep and stress coping.
2020 / Narrative Review / Preliminary evidenceReview found preclinical evidence for CBD benefits relevant to athletes (pain, inflammation, anxiety), but no studies have directly tested CBD in athletic populations.
2020 / Randomized Controlled Trial / Strong evidenceSAVANT trial subgroup analysis showed nabiximols halved MS spasticity and pain scores consistently across all disability levels, with severe patients showing the most significant gains.
2020 / Review / Strong evidenceReview of pharmaceutical CBD for epilepsy synthesized 4 pivotal RCTs showing significant seizure reduction in DS and LGS, with important drug interactions via CYP2C19.
2020 / Review / Preliminary evidenceReview plus clinical experience found early evidence that cannabis and CBD may help ASD symptoms and comorbidities, but large controlled trials are needed.
2020 / Review / Moderate evidenceThree small trials (93 subjects) showed cannabis improved Crohn disease symptoms but mostly did not reduce inflammation markers, raising questions about symptomatic versus disease-modifying effects.
2020 / Prospective Cohort / Moderate evidenceGeorgia expanded access program found sustained seizure reduction over 36 months in 45 children with treatment-resistant epilepsy on CBD, with adverse events decreasing over time.
2020 / Systematic Review / Moderate evidenceSystematic review found 10 of 12 studies support a cannabis-psychosis link, with THC identified as the primary risk and CBD as potentially therapeutic.
2020 / Animal Study / Moderate evidenceResearchers discovered CBD inhibits methionine synthesis through one-carbon metabolism, a new mechanism validated in Dravet syndrome mouse and rat seizure models.
2020 / Pilot Study / Preliminary evidenceIn 3 infants with rare KCNT1 epilepsy, CBD showed limited benefit: 2 had no response, 1 had reduced seizure intensity and possible developmental progress.
2020 / Case Report / Preliminary evidenceA 15-year-old with autism showed unexpected improvements in core social deficits, anxiety, and sleep on low-dose CBD extract originally prescribed for epilepsy.
2020 / Case Report / Preliminary evidenceA 9-year-old with Lennox-Gastaut syndrome achieved complete seizure control and dramatic EEG normalization on CBD, an improvement not previously described.
2020 / Observational / Preliminary evidenceIn vitro study found pure CBD matched or exceeded commercial CBD oils at reducing cancer cell viability, with some oils appearing to protect cancer cells.
2020 / Animal Study / Moderate evidenceRat study found CBD disrupted fear memory consolidation within a 1-hour window, using CB1/CB2 receptors immediately but PPARγ receptors at the 1-hour mark.
2020 / Observational / Preliminary evidenceHemp seed oil improved immune cell membrane composition and inflammatory markers in an MS mouse model, with additive benefits alongside rapamycin.
2020 / Systematic Review / Moderate evidenceSystematic review found THC impaired facial emotion recognition in half of experiments while CBD improved it, with opposing brain activation for threatening faces.
2020 / Animal Study / Preliminary evidenceMouse study found CBD produced antidepressant effects by normalizing stress-induced DNA methylation changes in prefrontal cortex and hippocampus.
2020 / Animal Study / Preliminary evidenceMouse study found CBD reversed ARDS symptoms and increased apelin expression in lungs and blood, revealing a new CBD mechanism for respiratory inflammation.
2020 / Review / Moderate evidenceReview of recent trials found CBD reduces positive psychotic symptoms but not negative symptoms, with inconsistent cognitive effects and generally good tolerability.
2020 / Case Report / Preliminary evidenceCase report of lithium toxicity developing weeks after adding CBD, revealing a previously unknown drug interaction in a patient who subsequently became seizure-free on CBD alone.
2020 / Animal Study / Preliminary evidenceMouse study found CBD-rich extract dramatically increased a "probiotic" gut bacterium while simultaneously triggering intestinal inflammation and reducing gut integrity markers.
2020 / Systematic Review / Moderate evidenceSystematic review of 26 studies found insufficient evidence for cannabinoids as routine sleep treatments but promising leads for sleep apnea, insomnia, and PTSD nightmares.
2020 / Cross Sectional / Moderate evidenceSurvey of 451 healthcare professionals found over 80% support medical cannabis but 40-50% lack knowledge of cannabinoid pharmacology and clinical applications.
2020 / Observational / Preliminary evidenceA CB2 receptor agonist increased epithelial cell growth and reduced inflammatory markers in colon tissue from IBD patients, suggesting cannabinoid receptors could help promote gut healing.
2020 / Randomized Controlled Trial / Moderate evidenceA randomized trial found that abruptly stopping 1,500 mg/day CBD after four weeks produced virtually no withdrawal symptoms in healthy volunteers.
2020 / Observational / Moderate evidenceAn open-label study of 38 children with treatment-resistant epilepsy found no cognitive decline after one year of add-on CBD treatment, with some trends toward improvement.
2020 / Animal Study / Preliminary evidenceImplantable polymer microdepots provided sustained release of full-spectrum cannabis extract for 14+ days in mice, reducing seizure incidence by 40% and improving survival by 50% compared to a single injection.
2020 / Animal Study / Preliminary evidenceTerpineol reduced depressive-like behavior in an inflammatory mouse model, with effects mediated through CB1, CB2 cannabinoid receptors and D2 dopamine receptors.
2020 / Animal Study / Preliminary evidenceTwo weeks of daily CBD altered DNA methylation at 3,323 sites in mouse hippocampus, affecting genes linked to neural development and psychiatric conditions.
2020 / Animal Study / Preliminary evidenceChronic CBD at 50 mg/kg did not improve motor, anxiety, or cognitive measures in 4-month-old TAU58/2 transgenic male mice, despite previous success in amyloid-based AD models.
2020 / Animal Study / Preliminary evidenceA comprehensive study of 8 phytocannabinoids found partial agonist activity at CB1 and/or CB2 receptors for multiple minor compounds, with several producing cannabinoid-like behavioral effects in mice.
2021 / Animal Study / Preliminary evidenceSeven days of high-dose CBD produced antidepressant-like effects in mice by increasing hippocampal serotonin and noradrenaline, the same neurotransmitters targeted by conventional antidepressants.
2021 / Systematic Review / Moderate evidenceA systematic review of 11 controlled trials found insufficient evidence for THC or CBD in schizophrenia treatment, with THC potentially worsening psychosis and CBD showing inconsistent benefits.
2021 / Animal Study / Preliminary evidenceCBD reduced the rewarding and anxiety-producing effects of the bath salt MDPV in mice, but unexpectedly increased drug-seeking in high-responding mice, revealing complex interactions.
2021 / Systematic Review / Moderate evidenceA systematic review found consistent preclinical evidence and two positive clinical trials supporting endocannabinoid system modulation for HIV-associated neuropathic pain.
2021 / Observational / Preliminary evidenceAdding CBD (200-800 mg/day) to stable SSRI treatment increased citalopram blood levels by ~50% in anxiety patients — a clinically significant drug interaction.
2021 / Animal Study / Preliminary evidenceCBGA showed anticonvulsant effects in Dravet syndrome mice and potentiated clobazam, but was proconvulsant in another seizure model and at high doses, revealing a complex therapeutic profile.
2021 / Animal Study / Preliminary evidenceCBDA blood levels were 14 times higher from cannabis extract than from isolated CBDA, because other cannabinoids (CBG, THC) blocked the intestinal efflux pump BCRP that normally limits CBDA absorption.
2021 / Animal Study / Preliminary evidenceTHC and CBD synergistically killed pediatric brain tumor cells in the lab through multiple mechanisms, but failed to improve survival in mouse brain tumor models, highlighting the gap between lab and clinical results.
2021 / Observational / Preliminary evidenceA CBD-rich cannabis extract reduced inflammatory markers in lung cells but increased them in macrophages, highlighting the cell-type-specific and potentially contradictory effects of cannabinoids on inflammation.
2021 / Randomized Controlled Trial / Moderate evidenceAn RCT of 150 autistic participants found a 20:1 CBD:THC extract improved disruptive behavior (49% vs 21%) and social responsiveness but not the primary behavioral outcome measure.
2021 / Review / Moderate evidenceCBD interacts with a wide range of medications including anti-epileptics, antidepressants, opioids, and even common drugs like acetaminophen. The interactions occur primarily through effects on liver enzymes that metabolize other drugs.
2021 / Narrative Review / Preliminary evidenceA review of 10 clinical studies found CBD may reduce psychotic symptoms caused by THC and positive symptoms of schizophrenia, though results for treating cannabis use disorder were mixed.
2021 / Case Report / Preliminary evidenceA Turkish clinic treated 33 autistic children with low-dose CBD-enriched cannabis for a median of 6.5 months. About a third showed improved behavior, and nearly a quarter improved in language, with no significant side effects.
2021 / Review / Moderate evidenceCBD's proven success treating severe epilepsy has opened the door to investigating its potential for depression, anxiety, PTSD, addiction, and autism. Preclinical and early clinical data show promise across multiple neuropsychiatric conditions.
2021 / Cross Sectional / Preliminary evidenceAmong 878 fibromyalgia patients using CBD, 72% reported substituting it for other medications. Over half substituted for opioids, and most said they reduced or stopped those medications entirely.
2021 / Cross Sectional / Preliminary evidenceA survey of 2,701 fibromyalgia patients found about a third currently use CBD, mainly for pain. Most reported improvement, but two-thirds who told their doctor did not ask for physician guidance on CBD use.
2021 / Review / Preliminary evidenceCannabis and THC show no benefits for athletic performance and may impair cardiovascular function during exercise. CBD shows more promise for recovery, potentially aiding sleep, pain management, and mild traumatic brain injury recovery.
2021 / Case Report / Preliminary evidenceEight infants with treatment-resistant West syndrome received CBD-enriched cannabis oil. Four achieved more than 50% seizure reduction, with EEG improvements in seven of eight. Side effects were mild and temporary.
2021 / Review / Preliminary evidenceA perspective piece warns that many reported CBD lab activities may be false positives caused by the substance forming tiny particles in solution, rather than genuine drug interactions. This could reshape cannabinoid research.
2021 / Review / Preliminary evidenceReview of preclinical evidence suggests CBD may help clear toxic protein aggregates in neurodegenerative diseases by modulating the proteostasis network, though human data remains limited.
2021 / Cross Sectional / Moderate evidenceSurvey of 200 osteoarthritis patients found 24% had tried CBD products, but CBD users reported significantly worse pain scores than non-users at their initial orthopedic evaluation.
2021 / Animal Study / Preliminary evidenceRats exposed to THC around birth showed lasting epigenetic changes in dopamine receptor genes and schizophrenia-like behaviors, but adolescent CBD treatment reversed the damage. Similar epigenetic changes were found in human schizophrenia patients.
2021 / Observational / Moderate evidenceComprehensive screen of 12 cannabinoids against 6 liver enzymes found CBD and THC were the strongest inhibitors, with minor cannabinoids in full-spectrum products adding additional risk.
2021 / Randomized Controlled Trial / Preliminary evidencePilot RCT of CBD in eight children with intellectual disability found 100% adherence, no serious side effects, and a preliminary signal of benefit for severe behavioral problems.
2021 / Systematic Review / Strong evidenceThird potency monitoring report: THC continued rising through 2019, but the THC:CBD ratio suddenly reversed as CBD products entered the market post-2018 Farm Bill.
2021 / Cross Sectional / Moderate evidenceSurvey of 239 young LA cannabis users found CBD-dominant product users were more medically motivated and reported more pain, but also used more illicit drugs, especially psilocybin.
2021 / Review / Strong evidenceCBD is approved for three epilepsy syndromes based on multiple RCTs, but its interaction with clobazam (boosting active metabolite levels) makes it difficult to isolate CBD's independent antiseizure contribution.
2021 / Systematic Review / Moderate evidenceSystematic review found CBD effective in rodent MS models but clinical results in humans were limited and usually negative, possibly because doses tested were too low.
2021 / Animal Study / Preliminary evidenceCBD reversed behavioral symptoms and molecular brain changes during spontaneous cocaine withdrawal in mice, normalizing dopamine and cannabinoid receptor gene expression.
2021 / Narrative Review / Moderate evidenceReview of 30 studies found CBD interacts with at least 15 anti-seizure medications through pharmacokinetic mechanisms and 3 through pharmacodynamic mechanisms, primarily via the cytochrome P450 system.
2021 / Animal Study / Preliminary evidenceStabilized CBDa hemp extracts showed seizure protection comparable to CBD in rats, with the multi-cannabinoid extract outperforming purified CBDa, supporting the entourage effect.
2021 / Systematic Review / Moderate evidenceSystematic review found THC and CBD have opposite brain effects, with THC increasing and CBD decreasing activation, particularly in regions linked to psychosis.
2021 / Meta Analysis / Strong evidenceMeta-analysis of 714 patients across 4 RCTs found CBD reduced seizures by about 30% in Dravet and Lennox-Gastaut syndromes, with 37-44% reduction when combined with clobazam.
2021 / Animal Study / Preliminary evidenceLab study found THC and THCA caused DNA damage in E. coli bacteria while other cannabinoids caused different types of cellular stress, with mixtures producing distinct patterns from individual compounds.
2021 / Randomized Controlled Trial / Preliminary evidencePhase I trial in 12 volunteers found CBD sublingual wafer achieved equivalent blood levels to oil solution and nabiximols spray, with mild drowsiness as the main side effect.
2021 / Randomized Controlled Trial / Preliminary evidenceSmall crossover trial found vaping 12.5 mg CBD modestly improved verbal memory recall (0.68 additional words) in 34 healthy young adults without affecting attention or working memory.
2021 / Systematic Review / Moderate evidenceSystematic review found multiple endocannabinoid system components show anti-inflammatory potential for IBD in preclinical studies, identifying CB1, CB2, FAAH, and MAGL as therapeutic targets.
2021 / Cross Sectional / Preliminary evidenceUK survey found autistic adults were 3.5 times more likely to use CBD than matched non-autistic adults, while reporting significant barriers to seeking cannabinoid-related healthcare support.
2021 / Prospective Cohort / Moderate evidenceItalian expanded access program found purified CBD achieved 50%+ seizure reduction in 40% of 82 patients with highly treatment-resistant Dravet or Lennox-Gastaut syndrome who had failed a median of 8 prior drugs.
2021 / Animal Study / Preliminary evidenceMouse study found twice-daily adolescent CBD exposure caused no harmful effects on locomotion, anxiety, or spatial memory in adulthood, with a possible learning enhancement.
2021 / Animal Study / Preliminary evidenceRat study found hempseed lipid extract improved cholesterol-related kidney damage more safely than simvastatin, modulating inflammatory pathways and oxidative stress.
2021 / Systematic Review / Moderate evidenceSystematic review of 22 studies found medical cannabis shows promise for fibromyalgia pain, with different THC/CBD ratios affecting different symptoms, though dosing and long-term data remain limited.
2021 / Prospective Cohort / Moderate evidenceProspective study of 35 children with drug-resistant epilepsy found CBD cut abnormal brain discharges nearly in half and improved sleep microstructure in 85% of those with initial sleep abnormalities.
2021 / Pilot Study / Preliminary evidenceSmall pilot trial of smoked CBD cigarettes for acute psychosis found no significant symptom differences, but the placebo group needed more antipsychotic medication while the CBD group did not.
2021 / Case Report / Preliminary evidenceCase series of 5 people with FASD found cannabis (mostly CBD) reduced disruptive behavior scores from 18 to 6, suggesting potential for a condition with very few treatment options.
2021 / Systematic Review / Moderate evidenceSystematic review of 10 studies found medical cannabis was safe and potentially beneficial for fibromyalgia, with only mild side effects and no serious adverse events.
2021 / Case Report / Preliminary evidenceCase report of a teenager with multiple substance addictions and depression who improved across all domains after switching from antidepressants to CBD, including quitting all illegal drugs.
2021 / Animal Study / Preliminary evidenceLab study found CBD protected rat brain tissue from simulated stroke damage while THC worsened it, with different receptor mechanisms mediating each effect.
2021 / Systematic Review / Moderate evidenceSystematic review of 42 studies found purified CBD effective for epilepsy beyond its approved indications, with preliminary evidence for CDKL5, Dup15q, Doose, and other rare syndromes.
2021 / Animal Study / Preliminary evidenceMouse study found CBD prevented cocaine relapse, abolished cocaine hyperactivity, and improved withdrawal memory deficits without producing reward itself.
2021 / Animal Study / Preliminary evidenceAn anandamide analog improved memory and reduced amyloid-beta in Alzheimer's model mice by activating CB2 cannabinoid receptors and promoting autophagy, a cellular cleanup process.
2021 / Randomized Controlled Trial / Moderate evidenceThree clinical trials found topical CBD and PEA products caused no skin irritation or sensitization in healthy adults, with only mild phototoxicity from one hemp seed oil product.
2021 / Observational / Moderate evidenceA lab study comparing six purified CBD samples found no pharmacological differences between plant-derived and synthetic CBD across cancer, stroke, and intestinal inflammation models.
2021 / Meta Analysis / Strong evidenceA meta-analysis of 31 randomized controlled trials found only limited evidence that cannabinoid products help with certain psychiatric symptoms short-term, and no evidence for mid- to long-term effectiveness for any psychiatric disorder.
2021 / Animal Study / Preliminary evidenceCBD treatment in rats protected hippocampal neurons from ischemia damage, preserved dendritic spines and BDNF levels, and prevented ischemia-induced memory deficits.
2021 / Case Report / Preliminary evidenceA schizophrenia patient hospitalized 30 times in 8 years reported significantly less need for illegal cannabis and no further hospitalizations after switching to low-THC CBD cigarettes.
2021 / Randomized Controlled Trial / Moderate evidenceTwo controlled studies found cannabis reliably increased psychotic-like symptoms, but CBD in the cannabis did not reduce these effects. Adolescents were actually less vulnerable to acute psychotic effects than adults.
2021 / Animal Study / Preliminary evidenceCBD prevented anxiety, memory loss, and depressive behavior after brain ischemia in mice, working through four different receptor systems including CB1, CB2, serotonin, and PPAR-gamma.
2021 / Prospective Cohort / Moderate evidenceA study of 20 breastfeeding mothers found THC concentrated in breast milk at 7 times plasma levels, with mothers increasing cannabis use in the early postpartum period.
2021 / Randomized Controlled Trial / Moderate evidenceA double-blind trial of 56 Crohn's patients found CBD-rich cannabis oil improved symptoms and quality of life but did not change endoscopic scores or inflammatory markers, raising questions about symptom masking.
2021 / Randomized Controlled Trial / Preliminary evidenceSmall crossover trial finds CBD increases hippocampal glutamate in psychosis patients, correlating with reduced symptom severity.
2021 / Randomized Controlled Trial / Preliminary evidencefMRI study finds single CBD dose partially normalizes altered brain activation in psychosis patients toward patterns seen in healthy controls.
2021 / Animal Study / Preliminary evidenceMouse study finds CBD prevents psychosis-like behavior with effects lasting 24 hours, involving DNA methylation changes in brain regions implicated in schizophrenia.
2021 / Animal Study / Preliminary evidenceRat study finds CBD enhances motor neuron survival by 54% after neonatal nerve injury, with sustained benefits at 8 weeks through CB1 receptor-dependent mechanisms.
2021 / Retrospective Cohort / Moderate evidenceReal-world study of 279 patients finds CBD-rich treatment significantly improves pain, anxiety, and depression at 3 months, but only in those with moderate-to-severe symptoms.
2021 / Randomized Controlled Trial / Moderate evidenceDouble-blind crossover study in 18 cannabis users finds CBD significantly reduces THC's psychotic-like effects when co-administered as a full-spectrum extract.
2021 / Observational / Preliminary evidenceFemale rats showed biphasic THC anxiety responses that males didn't — anxiolytic at low doses, anxiogenic at high. CBD blocked the anxiety and enhanced the calm.
2021 / Observational / Preliminary evidenceIn vitro study found CBD selectively suppressed two pro-inflammatory cytokines (IL-1β and IL-6) in human immune cells while leaving 11 other immune signals unaffected, revealing a targeted anti-inflammatory profile.
2021 / Retrospective Cohort / Preliminary evidenceReal-world study of 18 adults with Dravet syndrome found CBD reduced seizures by over 30% in 17.6%, but adverse effects were universal and led to discontinuation in some patients.
2021 / Systematic Review / Moderate evidenceSystematic review found only 8 small RCTs testing cannabinoids for depression, anxiety, or PTSD, with insufficient evidence to recommend cannabis for any of these conditions.
2021 / Longitudinal Cohort / Moderate evidenceStudy of 418 epilepsy patients found artisanal CBD users reported better quality of life, fewer psychiatric symptoms, and reduced healthcare utilization compared to non-users, though seizure control was similar.
2021 / Randomized Controlled Trial / Preliminary evidenceIn UC patients, endocannabinoid levels dropped in the placebo group but remained stable with cannabis treatment, and changes correlated with symptom improvements in bowel movements and quality of life.
2021 / Randomized Controlled Trial / Strong evidenceLandmark RCT of 224 patients found CBD significantly reduced TSC-associated seizures by about 49%, with the lower dose (25 mg/kg/day) as effective as the higher dose but with fewer side effects.
2021 / Prospective Cohort / Moderate evidenceProspective study of 92 epilepsy patients found 25% developed tolerance to CBD-enriched oil after a mean of 7.3 months, though 54% achieved meaningful seizure reduction overall.
2021 / Review / Preliminary evidencePK modeling and adverse event data show cannabis and CBD can increase escitalopram and sertraline levels in adolescents, raising the risk of side effects like dizziness and fatigue.
2021 / Randomized Controlled Trial / Preliminary evidenceSmall randomized trial found a nanoparticle CBD oral spray was safe and achieved comparable plasma levels to other formulations, with peak absorption at 60 minutes and no adverse effects.
2021 / Animal Study / Preliminary evidenceFirst study of developmental CBD exposure found mice exposed in utero and during nursing showed increased anxiety and thousands of brain DNA methylation changes as adults, despite known benefits of direct CBD exposure.
2021 / Retrospective Cohort / Moderate evidenceDanish study of 78 children with severe epilepsy found CBD reduced seizures by 50%+ in 31% at 3 months, with Dravet/Lennox-Gastaut patients responding best (70%). Response declined to 20% at 24 months.
2022 / Randomized Controlled Trial / Preliminary evidenceSmall RCT of 50 type 2 diabetes patients found a CBD-dominant sublingual spray significantly reduced total cholesterol and HbA1c over 8 weeks with no serious adverse effects.
2022 / Case Report / Preliminary evidenceThree young men with autism developed mania or psychosis after using CBD/THC products, highlighting potential psychiatric risks of cannabis use in the ASD population.
2022 / Animal Study / Preliminary evidenceNano-chitosan-coated CBD reduced amyloid plaques, increased brain cannabinoid receptors, and improved memory performance in an Alzheimer rat model.
2022 / Randomized Controlled Trial / Moderate evidenceCombined RCT data from 40 participants found minimal sex differences in acute vaporized cannabis effects, with males showing only slightly better divided attention and higher metabolite levels.
2022 / Review / Preliminary evidenceA review of CBD science following Malawi's cannabis legalization highlights epilepsy treatment, neuroprotective potential, and a novel proposal for malaria-related brain injury.
2022 / Animal Study / Moderate evidenceA rat study found high-THC cannabis smoke impaired working memory but not attention, while high-CBD smoke caused no cognitive deficits.
2022 / Animal Study / Moderate evidenceCBD disrupted fear memory reconsolidation in rats through CB1 receptors in the anterior cingulate and prelimbic cortex, not the infralimbic cortex.
2022 / Animal Study / Preliminary evidenceA stabilized CBDA derivative reduced weight and improved metabolic markers in both diet-induced and genetically obese mouse models.
2022 / Review / Moderate evidenceA review finds CBD has evidence for reducing anxiety, but THC effects are mixed. Despite limited evidence, anxiety cannabis prescriptions are rising rapidly in Australia.
2022 / Pilot Study / Preliminary evidenceAn open-label trial of 31 young people with treatment-resistant anxiety found 12 weeks of add-on CBD (up to 800 mg/day) reduced anxiety severity by 42.6%.
2022 / Randomized Controlled Trial / Moderate evidenceA controlled study found vaporized CBD reached 8-12x higher blood levels than oral CBD at the same dose, and pure CBD did not produce THC in the body.
2022 / Randomized Controlled Trial / Moderate evidenceA novel oral cannabis delivery system (Solutech) produced faster, higher blood levels of THC and CBD than standard oil, and cannabis use history significantly shaped pharmacokinetic profiles.
2022 / Meta Analysis / Strong evidenceA meta-analysis of 152 RCTs found CBD has high-grade evidence for epilepsy, while dronabinol and nabiximols show moderate evidence for pain, spasticity, and other conditions.
2022 / Animal Study / Preliminary evidenceTesting cannabis compounds in human immune cells found THC had the broadest anti-inflammatory activity, while popular terpenes like limonene had no measurable immune effects.
2022 / Cross Sectional / Moderate evidenceA survey of 878 fibromyalgia patients found typical CBD doses under 50 mg/day, with no relationship between dose and reported benefit, and most patients guided by personal research rather than doctors.
2022 / Animal Study / Preliminary evidenceA CBD-and-terpene-enriched cannabis extract reduced brain immune cell inflammation more effectively than pure CBD alone, through multiple molecular pathways.
2022 / Animal Study / Preliminary evidenceThe synthetic mirror image of CBD, (+)-CBD, was 10 times more potent at blocking CB1 signaling than natural (-)-CBD and activated an entirely different receptor system.
2022 / Review / Moderate evidenceA review finds fibromyalgia patients have altered endocannabinoid systems and that cannabinoid treatments show promise, but methodological gaps prevent clinical recommendations.
2022 / Prospective Cohort / Moderate evidenceA 20-month study of 59 children with drug-resistant epilepsy found CBD-enriched cannabis reduced seizures by 71% on average, with 12% achieving seizure freedom.
2022 / Cross Sectional / Moderate evidenceA French national survey found 10% of adults use CBD, with users tending to be younger, in poorer health, and viewing CBD as harmless.
2022 / Cross Sectional / Preliminary evidenceA survey of 70 psychosis patients found 86% willing to try CBD treatment, with most expecting symptom improvement and fewer side effects than antipsychotics.
2022 / Review / Moderate evidenceA review argues CBD's antipsychotic effects and low side effect profile make it potentially ideal for early-phase psychosis, where minimizing adverse experiences is crucial.
2022 / Pilot Study / Preliminary evidenceA pilot study of nanoparticle THC/CBD spray in 25 advanced cancer patients showed acceptable bioavailability, general safety, and preliminary pain relief, especially for bone metastases.
2022 / Retrospective Cohort / Moderate evidencePharmaceutical CBD achieved 2.4x higher blood levels than artisanal CBD in children with epilepsy, with more side effects but a trend toward better seizure control.
2022 / Review / Preliminary evidenceA review argues that combining CBD and THC may treat Alzheimer's more effectively than either alone, based on preclinical evidence of complementary neuroprotective mechanisms.
2022 / Narrative Review / Preliminary evidencePreclinical evidence for cannabinoids in Parkinson's and Alzheimer's is promising, but older adults are using them off-label despite almost no clinical trial data.
2022 / Prospective Cohort / Moderate evidenceMedical cannabis patients showed improved brain white matter coherence on MRI over 6 months, contrasting with impairments in recreational users, with CBD exposure linked to improvements.
2022 / Pilot Study / Preliminary evidenceAn open-label trial of full-spectrum CBD in 14 anxiety patients showed rapid response within one week, with improvements in anxiety, cognition, mood, and sleep over 4 weeks.
2022 / Animal Study / Preliminary evidenceLab study showed CBD reduced inflammatory vesicles released from HIV-infected immune cells, potentially by lowering viral activity.
2022 / Animal Study / Preliminary evidenceA high-CBD cannabis extract suppressed human T cell activity in the lab without killing cells, working mainly through CB2 and TRPV1 receptors.
2022 / Animal Study / Preliminary evidenceCBD blocked THC-induced nausea in rats through 5-HT1A serotonin receptors and also reversed THC-induced stress hormone elevation.
2022 / Animal Study / Preliminary evidenceFour rare cannabinoids (CBG, CBC, THCV, CBGA) each uniquely modulated the endocannabinoid system in human skin cells but shared common effects on receptor binding.
2022 / Review / Preliminary evidenceReview finds early evidence that CBD may safely improve symptoms of autism, intellectual disability, tics, and ADHD in children and adolescents.
2022 / Animal Study / Preliminary evidenceResearch suggests CBD may work partly by changing DNA methylation patterns, offering a new explanation for its broad effects on anxiety, depression, and psychosis.
2022 / Review / Preliminary evidenceNarrative review found emerging evidence that CBD may address positive, negative, and cognitive symptoms of schizophrenia with fewer side effects than standard antipsychotics.
2022 / Animal Study / Preliminary evidenceA CBD-rich cannabis extract killed human pancreatic cancer cells in 3D models through apoptosis pathways that the standard drug gemcitabine alone did not activate.
2022 / Animal Study / Preliminary evidenceLow-THC broad-spectrum cannabis oil reversed pain, thermal sensitivity, and depression in a mouse fibromyalgia model at doses as low as 0.1 mg/kg.
2022 / Systematic Review / Moderate evidenceCochrane review of 25 trials found nabiximols probably reduces MS spasticity (moderate certainty) but uncertain evidence for chronic pain, with modestly increased side effects.
2022 / Scoping Review / Preliminary evidenceScoping review found 61-93% of children with autism showed improvement with medicinal cannabis in small studies, with up to 80% reducing other medications.
2022 / Cross Sectional / Preliminary evidenceSurvey of 428 arthritis patients found CBD was associated with 44% average pain reduction, and 60% reduced or stopped other medications including opioids.
2022 / Animal Study / Preliminary evidenceCBD disrupted fear memory reconsolidation in female rats through hippocampal CB1 receptors, reducing fear behavior for over a week without reinstatement.
2022 / Animal Study / Preliminary evidenceCBD combined with a ginseng compound in nanoparticles achieved 82% tumor inhibition in breast cancer mice with good tolerability.
2022 / Randomized Controlled Trial / Moderate evidenceTrial found cannabis flower with balanced THC:CBD produced similar positive effects but significantly less anxiety and paranoia than THC-dominant flower.
2022 / Randomized Controlled Trial / Moderate evidenceControlled trial showed THC and CBD each altered brain responses to unexpected sounds, with CBD modifying THC's effects differently in frequent vs less-frequent users.
2022 / Review / Preliminary evidenceReview of 77 published case reports found only 14% provided strong evidence for cannabis anticancer effects, with 81% rated weak and no supporting clinical trial data.
2022 / Narrative Review / Moderate evidenceTHC modulates reward-related brain regions in ways that correlate with psychotic symptoms. CBD appears to act in the opposite direction on the same regions.
2022 / Review / Preliminary evidenceTopical CBD may promote hair growth at low concentrations but cause loss at high concentrations. One trial saw a 93.5% increase in hair count over 6 months.
2022 / Pilot Study / Moderate evidence82 children with autism who completed 6 months of CBD-rich cannabis showed significant improvements in social communication on both clinical and parent-reported measures.
2022 / Review / Moderate evidenceCannabis-based treatments, especially nabiximols spray and oral cannabinoids, consistently helped with MS pain and spasticity but showed only slight improvement for other MS symptoms.
2022 / Narrative Review / Preliminary evidenceReview argues antidepressants are likely less effective in cannabis-using teens, based on overlapping neurochemical pathways, but no clinical trials have tested this directly.
2022 / Review / Moderate evidenceStandard ASD medications often cause side effects that mimic ASD symptoms. Early evidence suggests CBD-rich cannabis may be effective and better tolerated, but controlled trials are needed.
2022 / Randomized Controlled Trial / Strong evidenceCannabis with equal THC and CBD caused less anxiety than THC alone. CBD fully blocked THC anxiety in calm users but not in those with high baseline anxiety.
2022 / Animal Study / Moderate evidenceMouse pups exposed to CBD prenatally showed sex-specific disruptions: males gained extra weight and changed vocalizations, while females had impaired motor and discrimination abilities.
2022 / Narrative Review / Preliminary evidenceCannabinoids including CBD and CBGA have anti-inflammatory and antiviral properties that could theoretically help with COVID-19, but no clinical evidence exists.
2022 / Animal Study / Moderate evidenceIn a schizophrenia rat model, THC-only cannabis vapor worsened brain oscillation deficits while balanced THC/CBD vapor preserved or enhanced brain activity.
2022 / Animal Study / Moderate evidenceIn rats with nerve injury pain, CBD enhanced morphine's effectiveness at sub-therapeutic doses and partially prevented morphine tolerance development.
2022 / Observational / Strong evidenceLab testing found THC in 65% of 80 CBD products, including 24% of those labeled "THC-Free," with concentrations up to 2 mg/mL.
2022 / Observational / Strong evidenceNearly half of 80 CBD products tested had CBD concentrations more than 10% off their labels, with some containing less than half the advertised amount.
2022 / Animal Study / Moderate evidenceIn rats, CBD reduced risperidone-induced blood sugar elevation, movement abnormalities, and muscle stiffness without impairing cognition.
2022 / Narrative Review / Preliminary evidenceCBD and THC do not boost athletic performance. CBD's anti-inflammatory potential remains untested in sport. Some CBD products may trigger positive drug tests due to THC contamination.
2022 / Review / Moderate evidenceAfter 30 years of research, only two formal medical cannabis indications are supported by evidence: CBD for rare childhood epilepsy and CBD/THC for MS spasticity.
2022 / Prospective Cohort / Moderate evidenceCBD reduced seizures by 50%+ in 27% of 41 children with severe epilepsy, but quality of life and adaptive behavior did not improve over six months.
2022 / Scoping Review / Moderate evidenceOnly 16 controlled studies exist for CBD in psychiatric disorders. Most promising evidence for psychosis and anxiety, but not enough for clinical recommendations in any condition.
2022 / Review / Moderate evidenceMost evidence supports cannabis for pain, but no head-to-head comparison exists between preparations. The entourage effect lacks systematic support for pain.
2022 / Review / Preliminary evidenceCBD has multiple properties relevant to opioid withdrawal management and is safe with opioids, but large clinical trials are needed before it can be recommended as an adjunct treatment.
2022 / Case Report / Preliminary evidenceTopical 20% CBD oil resolved both biopsy-confirmed squamous cell carcinoma and lichen simplex chronicus on a 64-year-old woman's hands.
2022 / Case Report / Preliminary evidenceA 9-year-old with nonverbal autism showed reduced violent outbursts, better sleep, and improved social interactions after starting full-spectrum CBD oil with low-dose THC.
2022 / Cross Sectional / Preliminary evidenceCanadian survey found nearly one in four respondents used cannabis topically, most commonly for joint stiffness, headaches, and skin conditions, with dispensaries as the primary information source.
2022 / Review / Preliminary evidenceReview found topical CBD has demonstrated anti-inflammatory, anti-itch, wound healing, and anti-proliferative effects on skin through cannabinoid receptors, positioning it as a potential corticosteroid alternative.
2022 / Case Report / Preliminary evidenceThree young men with ADHD showed measurable improvements in depression, anxiety, emotional regulation, and inattention after adding cannabis, with plasma levels confirming cannabinoid presence.
2022 / Retrospective Cohort / Moderate evidenceStandardized CBD oil reduced seizures by 50%+ in 73% of treatment-resistant epilepsy patients and achieved seizure freedom in 19% over 40 months, with few side effects.
2022 / Review / Moderate evidenceReview found topical cannabinoid products show promise for atopic dermatitis, psoriasis, and contact dermatitis based on skin endocannabinoid system biology, but large clinical trials are still needed.
2022 / Review / Strong evidenceEpidiolex (pharmaceutical CBD) is the only cannabis-derived drug with FDA and EMA approval for epilepsy, specifically proven for Dravet syndrome, Lennox-Gastaut syndrome, and tuberous sclerosis complex.
2022 / Pilot Study / Preliminary evidencePilot trial of oral cannabinoids in HIV-positive patients on antiretroviral therapy found them generally safe with stable CD4 counts and viral suppression, supporting larger studies.
2022 / Randomized Controlled Trial / Moderate evidenceCrossover RCT found oral CBD up to 1,500 mg did not impair simulated driving or cognition compared to placebo, though high-dose CBD persisted in blood for over 4 weeks.
2022 / Randomized Controlled Trial / Moderate evidenceIn 515 roadside drug tests after oral CBD up to 1,500 mg, zero false-positive THC results were observed, confirming pure CBD does not trigger standard cannabis drug tests.
2022 / Systematic Review / Moderate evidenceSystematic review found mostly lab-based evidence for cannabis in endometriosis with conflicting results. Few human studies exist, and UK guidance currently cannot recommend cannabis for this condition.
2022 / Review / Strong evidenceCritical review of 69 articles confirmed CBD is effective for Lennox-Gastaut, Dravet, and tuberous sclerosis complex seizures in children, with a good safety profile despite frequent mild side effects.
2022 / Animal Study / Preliminary evidenceCBD reduced anxiety, agitation, and physical withdrawal symptoms in heroin-dependent mice while normalizing gene expression changes in brain reward regions.
2022 / Prospective Cohort / Preliminary evidenceCancer patients taking 300 mg/day CBD showed reduced early peripheral neuropathy symptoms during chemotherapy, with particular benefit seen in vibrometry scores and cold sensitivity.
2022 / Systematic Review / Strong evidenceMeta-analysis found cannabinoids reduced effective morphine dose 3.5x in animals but human RCTs showed no opioid-sparing effect. Observational studies were more positive, highlighting a research-design gap.
2022 / Systematic Review / Moderate evidenceSystematic review of RCTs found cannabinoids improved Tourette tics and some Parkinson's symptoms but showed no benefit for dystonia. Evidence is limited by small, heterogeneous trials.
2022 / Pilot Study / Preliminary evidenceSmall pilot study of 20 patients found a CBD-melatonin sublingual compound improved sleep quality, reduced anxiety, and decreased pain over 3 months, but lacked a control group.
2022 / Review / Moderate evidenceReview found CBD shows biological plausibility and early promise for ASD symptoms through the endocannabinoid system, but clinical evidence is limited and the authors caution against premature use.
2022 / Observational / Moderate evidenceAnalysis of U.S. dispensary products found medical cannabis THC:CBD ratios are nearly identical to recreational products — most would produce significant intoxication rather than therapeutic benefit.
2022 / Randomized Controlled Trial / Moderate evidencePhase 1 trial of CBD-dominant cannabis oil in 43 healthy adults found dose-proportional CBD absorption, mostly mild side effects, and recommended starting doses no higher than 240 mg CBD daily.
2022 / Animal Study / Preliminary evidenceModeling predicted THC could increase methylphenidate levels by 34% and high-dose CBD by up to 55% through CES1 enzyme inhibition, a previously unreported drug interaction mechanism.
2022 / Observational / Preliminary evidenceIn vitro testing found higher CBD concentrations increased some inflammatory markers in blood from depressed patients, challenging the assumption that CBD is uniformly anti-inflammatory.
2022 / Systematic Review / Strong evidenceUmbrella review of 68 systematic reviews found no high-certainty evidence for cannabinoids in any condition. Moderate evidence supported chemotherapy nausea benefit; no benefit found for chronic non-cancer pain.
2022 / Animal Study / Preliminary evidenceIn epileptic rats, THC doubled seizure activity while CBD halved it — and smoked high-THC cannabis increased seizures too, highlighting the importance of cannabinoid ratios.
2022 / Case Report / Preliminary evidenceParents secretly administered a CBD extract to their 4-year-old with brain inflammation, not telling doctors because they assumed the legal product was safe, highlighting risks of unregulated self-prescribing.
2022 / Randomized Controlled Trial / Preliminary evidencePilot RCT of 9 trained runners found 300 mg CBD appeared to increase oxygen consumption, exercise pleasure, and VO2max without affecting endurance performance or heart rate.
2022 / Randomized Controlled Trial / Strong evidencePlacebo-controlled trial of 150 children with autism found CBD-rich cannabis treatment was not better than placebo for any aspect of sleep.
2022 / Systematic Review / Moderate evidenceSystematic review of 9 studies found cannabis products reduced hyperactivity, anxiety, sleep problems, and irritability while improving cognition and social interaction in autism.
2022 / Meta Analysis / Strong evidenceMeta-analysis of 6 trials with 1,034 patients confirmed CBD reduces seizure frequency by 33% in Dravet syndrome, Lennox-Gastaut, and tuberous sclerosis complex.
2022 / Pilot Study / Moderate evidencePhase III interim analysis of 59 children with autism found CBD-rich cannabis oil (20:1 CBD:THC) produced no clinically significant blood chemistry changes over 3 months.
2022 / Animal Study / Preliminary evidenceMenopausal mice treated with CBD for 18 weeks had improved blood sugar, bone density, and energy expenditure, along with increased gut Lactobacillus.
2022 / Systematic Review / Strong evidenceSystematic review of 58 CBD trials found consistent anxiolytic effects but highly variable results for psychosis, substance use, and other non-seizure conditions.
2022 / Retrospective Cohort / Moderate evidenceRetrospective study of 114 children with drug-resistant epilepsy found 73% improved with CBD-enriched oil, with 59% achieving over 50% seizure reduction over at least one year.
2022 / Randomized Controlled Trial / Strong evidenceRigorous RCT of 136 arthritis patients found synthetic CBD 20-30 mg daily showed no pain benefit over placebo after 12 weeks.
2022 / Retrospective Cohort / Moderate evidenceSpanish expanded access program of 102 patients found CBD reduced seizures by 48%, with 45% achieving over 50% reduction at 6 months in highly refractory epilepsy.
2022 / Systematic Review / Moderate evidenceSystematic review of 8 RCTs found nabiximols, CBD, and PF-04457845 outperformed dronabinol and nabilone for cannabis use disorder, covering more treatment outcomes.
2022 / Cross Sectional / Preliminary evidenceSurvey of 76 eczema patients found universal support for medical cannabis and 94% interest in learning more, but 93% had never discussed it with their healthcare provider.
2022 / Animal Study / Preliminary evidenceMouse study found cannabis extracts reduced gut inflammation better than pure THC or CBD alone, with each treatment producing a distinct immune response pattern.
2023 / Randomized Controlled Trial / Moderate evidencePilot trial of 12 adults with Tourette syndrome found vaporized THC reduced tic urges and distress but did not significantly improve video-rated tic severity compared to placebo.
2023 / Animal Study / Preliminary evidenceAdolescent rats given CBD-enriched cannabis extract showed no behavioral changes but had significant hippocampal synaptic protein alterations, suggesting hidden molecular effects during brain development.
2023 / Review / Moderate evidenceReview found CBD therapeutic effects emerge at 300+ mg/day, with best evidence for anxiety and addiction. Most OTC products fall below this threshold.
2023 / Randomized Controlled Trial / Moderate evidenceControlled human study shows CBD (640 mg) inhibited four major drug-metabolizing enzyme families while THC alone had minimal effects — important for anyone combining CBD with prescription medications.
2023 / Randomized Controlled Trial / Moderate evidenceTriple-blind crossover trial found women had significantly higher blood CBD levels than men at the same dose, with CBD detectable up to 50 days after stopping.
2023 / Animal Study / Preliminary evidenceAnimal study found a whole cannabis extract and a pure 1:1 THC:CBD mix produced different pain-relief patterns and engaged different brain receptors, despite matching THC:CBD ratios.
2023 / Animal Study / Preliminary evidenceCBD reversed social behavior deficits, abnormal stress responses, and brain plasticity changes caused by adolescent binge drinking and social stress in a rat model.
2023 / Animal Study / Preliminary evidenceCell culture study found CBD and cannabis extracts reduced the effectiveness of platinum chemotherapy drugs by decreasing how much drug accumulated inside cancer cells.
2023 / Animal Study / Preliminary evidenceCBD given during adolescence rescued memory deficits and restored brain plasticity markers in rats prenatally exposed to THC, suggesting a potential therapeutic window.
2023 / Animal Study / Preliminary evidenceMouse study found CBD protected against Alzheimer's-related cognitive deficits by modulating microglial activity and inflammatory gene expression.
2023 / Systematic Review / Moderate evidenceSystematic review of 19 studies (1,927 pediatric cancer patients) found cannabinoids commonly used for chemotherapy nausea with no serious adverse events, but dosing evidence remains insufficient.
2023 / Observational / Preliminary evidenceUK registry study of 76 IBD patients found medical cannabis improved disease-specific quality of life, anxiety, and sleep at 1 and 3 months.
2023 / Prospective Cohort / Preliminary evidenceStudy of 186 young pregnant women found 20% had tried CBD, with pre-pregnancy substance use as the strongest predictor.
2023 / Observational / Preliminary evidenceCBG reduced key inflammatory markers in rheumatoid arthritis cells through the TRPA1 pain-sensing channel, with selectivity for inflamed over healthy tissue.
2023 / Narrative Review / Preliminary evidenceCBD consistently suppressed immune responses across animal and cell studies, but zero clinical trials have tested whether this helps humans with inflammatory diseases.
2023 / Retrospective Cohort / Moderate evidenceReal-world European data showed plant-derived CBD without clobazam reduced seizures by 50%+ in 30% of LGS patients at 12 months, with 63% still taking it at one year.
2023 / Prospective Cohort / Moderate evidenceAn open-label study found CBD-rich cannabis oil reduced seizures from 11 to 2.5 per month in adults with drug-resistant focal epilepsy, with 80% achieving 50%+ reduction.
2023 / Systematic Review / Moderate evidenceSystematic review found most studies report cannabinoid benefits for IBD symptoms, but heterogeneous methods prevent determining optimal dose, formulation, or delivery.
2023 / Cross Sectional / Preliminary evidenceA national survey of 1,158 Americans found CBD users perceived it as safe and helpful, but most reported adverse effects were moderate to severe, sometimes requiring medical attention.
2023 / Review / Moderate evidenceA review of purified CBD clinical trials found the strongest evidence for anxiety (17 RCTs), psychosis (8 RCTs), PTSD (4 RCTs), and substance abuse (3 RCTs), but not for pain or sleep.
2023 / Narrative Review / Preliminary evidenceReview found strong preclinical evidence for CBD improving cognition, but human studies have not confirmed these effects.
2023 / Scoping Review / Preliminary evidenceScoping review found preclinical support for cannabinoids in rheumatoid diseases but scarce and mixed clinical evidence.
2023 / Systematic Review / Moderate evidenceOnly 9 RCTs exist for CBD across all neurodevelopmental disorders, with inconsistent results.
2023 / Animal Study / Preliminary evidenceCBD reprogrammed human dendritic cells during long-term treatment to mount anti-inflammatory responses when activated, with IL-10 signaling as the dominant pathway.
2023 / Randomized Controlled Trial / Moderate evidencePhase 3 analysis found CBD did not worsen safety or effectiveness of diazepam nasal spray for seizure clusters, with purified CBD patients showing the lowest drug-attributed adverse event rates.
2023 / Animal Study / Moderate evidence90-day rat study found CBD improved antioxidant status safely, while CBG at similar doses caused liver damage, oxidative stress, and blood abnormalities.
2023 / Observational / Preliminary evidenceMachine learning found medical cannabis shifted salivary biomarkers in autistic children toward typical levels, with THC and CBD producing distinct metabolic signatures.
2023 / Case Report / Preliminary evidenceFirst case report of cannabis-assisted psychotherapy for dissociative PTSD showed dramatic improvement over 10 sessions, drawing parallels to psychedelic-assisted therapy.
2023 / Review / Strong evidenceReview of CBD (Epidiolex) clinical evidence shows efficacy for seizures in Dravet syndrome, Lennox-Gastaut syndrome, and tuberous sclerosis complex, with unresolved dosing and interaction challenges.
2023 / Lab Study / Preliminary evidenceLab study showed CBD oil and vitamin E acetate in vaping aerosols accumulated on and inside human airway cells, causing dramatic cell death and metabolic stress.
2023 / Lab Study / Preliminary evidenceComputational screening and lab testing found CBD selectively inhibits brain enzyme PDE9 at nanomolar concentrations, suggesting a potential neuroprotective mechanism.
2023 / Randomized Controlled Trial / Strong evidencePlacebo-controlled crossover trial found THC/CBD cannabis oil helped 60% of insomnia patients no longer qualify as clinical insomniacs, with increased melatonin and sleep duration.
2023 / Animal Study / Preliminary evidenceIn female rats, high-CBD cannabis vapor reduced opioid reward and fentanyl self-administration with no abuse potential and a robust safety profile.
2023 / Animal Study / Preliminary evidenceCBD injected into the amygdala reversed pain sensitivity caused by living with a partner in chronic pain, working through serotonin 5-HT3 receptors.
2023 / Review / Moderate evidenceReview found cannabis may help brain tumor patients with nausea, pain, appetite, and seizures, but standardized dosing guidance and clinical trials are lacking.
2023 / Lab Study / Strong evidenceStudy revealed CBD prevents seizures by blocking a lipid (LPI) that simultaneously boosts excitatory and weakens inhibitory signaling in the hippocampus through GPR55 receptors.
2023 / Randomized Controlled Trial / Preliminary evidencePilot RCT of 17 volunteers found 600mg CBD did not alter ayahuasca's effects on social cognition, with good tolerability and no safety concerns.
2023 / Animal Study / Preliminary evidenceCBD extended sleep in rats but disrupted sleep oscillations critical for memory, impairing complex memory consolidation while leaving simple memory intact.
2023 / Review / Moderate evidenceComprehensive review found CBD has documented benefits for epilepsy, anxiety, and pain, with emerging evidence for cognition and sleep, but called for better product regulation.
2023 / Umbrella Review / Strong evidenceUmbrella review of 25 systematic reviews found consistent evidence linking recreational cannabis to suicidal ideation and attempts, with dose-response patterns.
2023 / Observational / Preliminary evidenceIn 15 ASD children on medical cannabis, 22 salivary lipid biomarkers shifted toward typically developing levels, suggesting inflammation and oxidative stress pathways.
2023 / Observational / Preliminary evidenceMetabolomics analysis found 65 salivary biomarkers shifted toward typical levels in 15 ASD children on medical cannabis, including inflammation and neurotransmitter markers.
2023 / Retrospective Cohort / Preliminary evidenceWomen increasingly use cannabis for endometriosis, pelvic pain, and period cramps, with retrospective data suggesting benefit — but clinical trials are nearly nonexistent and barriers to medical access persist.
2023 / Review / Low evidenceReview examines CBD safety profile as an anti-inflammatory agent, noting general tolerability but flagging liver effects, drug interactions, and gaps in long-term data.
2023 / Review / Low evidenceReview of cannabinoids for multiple sclerosis finds preclinical promise and some clinical support for spasticity relief, but limited trial data overall.
2023 / Randomized Controlled Trial / Moderate evidenceControlled fMRI study found THC blunted reward-related brain activity in adults but not adolescents. Adding CBD partially offset the effect in adults.
2023 / Case Report / Very Low evidenceCase series reported hair regrowth with topical hemp extract containing CBD, THCV, and CBDV over 6 months. No control group.
2023 / Animal / Low evidenceRat study found CBD prevented the negative emotional conditioning associated with opioid withdrawal through 5-HT1A serotonin receptor activation.
2023 / Animal / Low evidenceCBD and cannabis-inspired terpene blends both improved social behavior in an autism mouse model within 30 minutes of administration.
2023 / Randomized Controlled Trial / Moderate evidenceCrossover RCT found 1:1 THC:CBD oil significantly reduced chemotherapy-induced nausea in 54 gynecologic cancer patients, though dizziness was common.
2023 / Animal / Low evidenceSingle-cell sequencing study found CBD reprogrammed tumor macrophages and enhanced anti-PD-1 immunotherapy response in a colon cancer mouse model.
2023 / Animal / Moderate evidence90-day rat toxicology study established CBD safety limits: NOAEL of 460 mg/kg/day (males) and 230 mg/kg/day (females), with most changes reversible.
2023 / Meta Analysis / High evidenceMeta-analysis of 6 RCTs confirms CBD (Epidiolex) significantly reduces seizures in Dravet, Lennox-Gastaut, and tuberous sclerosis complex, with notable side effects.
2023 / Observational / Preliminary evidenceCannabis extracts from four different plant varieties all inhibited liver enzymes that metabolize warfarin and other blood thinners — with interaction strength varying by chemotype.
2023 / Retrospective Cohort / Moderate evidenceReal-world study found prescribed CBD reduced seizures in a substantial proportion of epilepsy patients over 12 months with mostly mild side effects.
2023 / Observational / Preliminary evidenceFive high-CBD cannabis extracts reduced gut cell inflammation through microRNA pathways, suppressing COX-2, IL-6, and IL-8 — but high doses also slowed cell growth.
2023 / Animal / Low evidenceAnimal study found THC and CBD had distinct effects on BDNF and TrkB expression in the adolescent hippocampus, suggesting different impacts on brain development.
2023 / Narrative Review / Preliminary evidenceCannabinoids — especially CBD — show biological rationale for treating psoriasis through antioxidant and anti-inflammatory pathways, but clinical evidence in human patients remains minimal.
2023 / In Vitro / Very Low evidenceLab study found cannabis extracts reduced inflammatory cytokine release in human macrophages, supporting anti-inflammatory potential at the cellular level.
2023 / Randomized Controlled Trial / High evidenceRandomized trial found CBD dose-dependently altered THC blood levels and effects when co-administered orally in healthy adults.
2023 / Review / Low evidenceReview examines how plant and endogenous cannabinoids affect CNS diseases, finding diverse pharmacological activities with varying levels of clinical evidence.
2023 / Randomized Controlled Trial / High evidenceRandomized trial found 4 weeks of pharmaceutical CBD did not significantly improve symptoms in idiopathic or diabetic gastroparesis versus placebo.
2023 / Randomized Controlled Trial / High evidenceFour-arm randomized trial compared CBD, THC, CBD/THC combination, and placebo capsules for peripheral neuropathic pain.
2024 / Review / Moderate evidenceReview of 10 clinical trials confirms CBD reduces seizures in pediatric Dravet syndrome with manageable side effects and notable clobazam interactions.
2024 / Systematic Review / Moderate evidenceSystematic review found individual cannabis terpenes have exploratory therapeutic benefits, but the synergistic entourage effect with cannabinoids remains unproven.
2024 / Mini Review / Moderate evidenceReview of cannabinoid treatments for autism found encouraging but mixed evidence from clinical trials, with good safety profiles but not enough data to recommend CBD for ASD.
2024 / Animal Study / Low evidenceRat study found CBD reduced pain effectively in both sexes, but females in late diestrus responded to doses 10-fold lower than males, suggesting hormonal influence on CBD efficacy.
2024 / Computational Review / Low evidenceComputational analysis mapped how 8 phytocannabinoids interact with neurodegenerative disease targets through ErbB and PI3K-Akt pathways, with effects varying by sex, age, and disease.
2024 / Narrative Review / Moderate evidenceReview found FDA-approved CBD causes dose-dependent liver toxicity, with higher risk when combined with valproate, and current models cannot fully predict CBD safety.
2024 / Cross Sectional Survey / Moderate evidenceSurvey of 498 caregivers found CBD improved seizures in 85% of severe epilepsy patients, plus alertness, cognition, and emotional functioning even in some without seizure improvement.
2024 / Repeated Cross Sectional Survey / Moderate evidenceLarge survey found 20% of pregnant women used CBD-only products, nearly double the rate of non-pregnant women, primarily for anxiety, pain, and depression.
2024 / Quasi Experimental / Moderate evidenceFour-week study found CBD-dominant cannabis reduced anxiety, tension, and paranoia more than THC-dominant cannabis in people with anxiety symptoms, with THC not worsening anxiety.
2024 / Animal Study / Preliminary evidenceIn C. elegans worm models, CBD and THC both reduced pain responses but through entirely different receptor systems, with CBD effects wearing off within 6 hours while THC effects persisted.
2024 / Epidemiological / Moderate evidenceEuropean adverse event data on unlicensed CBD products found serious reactions in 18.9% of reports, most commonly liver problems, mental disorders, and worsening epilepsy, predominantly in men using CBD alongside antiepileptic drugs.
2024 / Observational / Moderate evidenceReal-world study of 91 adults found CBD showed similar effectiveness for drug-resistant epilepsy whether used for approved conditions or off-label, with clobazam co-prescription strongly predicting who responded.
2024 / Animal Study / Preliminary evidenceC. elegans exposed to CBD from early life showed irreversible developmental delays, with purified CBD slightly more toxic than hemp extract, though all adverse doses far exceeded human recommended levels.
2024 / Narrative Review / Preliminary evidenceComprehensive review maps cannabinoid drug interactions across epilepsy, cancer, MS, and pain — CYP450 inhibition by CBD and THC can significantly alter blood levels of co-administered medications.
2024 / Laboratory / Preliminary evidenceFirst study to test CBD-CAR T cell interaction found CBD reduced proliferation through apoptosis but preserved cancer-killing function and cytokine secretion, suggesting a complex but not necessarily harmful interaction.
2024 / Animal Study / Preliminary evidenceCBD reduced nicotine self-administration in mice without affecting food intake, and attenuated both physical withdrawal symptoms and withdrawal-related pain sensitivity, suggesting potential as a smoking cessation aid.
2024 / Randomized Controlled Trial / High evidenceCrossover RCT of 46 healthy volunteers found THC inhalation acutely raised anandamide and related lipids, but co-administered CBD at 10-30 mg did not influence these endocannabinoid changes.
2024 / Randomized Controlled Trial / High evidenceClinical trials in 75 volunteers found 800 mg oral CBD raised anandamide 1.6-fold, while combining CBD with THC boosted it to 2.1-fold, revealing a dose threshold and synergistic effect relevant to psychiatric treatment.
2024 / Laboratory / Preliminary evidenceLab study found cannabinoids preserved 70-89% of neuron viability (vs. 40% with chemo alone) and limited axon shortening to 23-44% (vs. 63%), suggesting potential for preventing chemotherapy-induced nerve damage.
2024 / Mixed Methods / Moderate evidenceMixed-methods study of 87 autistic children found 75% adhered to 6-month CBD-rich cannabis treatment with mild side effects and substantial reported benefits, though dosing complexity and unrealistic expectations were barriers for some families.
2024 / Clinical Trial / Strong evidenceControlled fMRI study found vaporized cannabis disrupted five major brain networks equally in teens and adults, and CBD co-administration did not reduce THC effects, challenging assumptions about CBD safety.
2024 / Observational / Preliminary evidenceA Colombian case series of 24 patients found 12 months of CBD oil (100-120 mg/day) reduced significant anxiety from 100% to 37.5% and improved sleep disturbances from 47% to 12.5%, with no significant adverse effects.
2024 / Clinical Trial / Strong evidenceA rigorous crossover trial of 37 volunteers found high-dose CBD increased THC blood levels by 118%, boosted "Feeling High" by 60%, and did not improve pain relief, contradicting the assumption that CBD reduces THC effects.
2024 / Clinical Trial / Preliminary evidenceOpen-label study of 20 daily e-cigarette users found 320 mg oral CBD reduced nicotine withdrawal severity and anxiety during a 4-hour abstinence period.
2024 / Randomized Controlled Trial / Moderate evidenceA crossover RCT with 48 cannabis users found THC eliminated the tendency to look away from cannabis images. CBD did not change this effect, and adolescents responded similarly to adults.
2024 / Cross Sectional / Moderate evidenceSurvey of 550 opioid addiction patients found 23% use CBD — primarily for anxiety, pain, and sleep, with 42% using it specifically for withdrawal relief.
2024 / Randomized Controlled Trial / Preliminary evidenceTwo Phase 1 trials of 83 healthy adults found one week of oral cannabis products reduced a marker of bone resorption, the first human evidence that cannabinoids may affect bone turnover.
2024 / Observational / Moderate evidenceAnalysis of 4,214 US Epidiolex prescriptions found 40% were off-label (sleep, anxiety, mood, autism), with nearly half of patients co-prescribed interacting benzodiazepines.
2024 / Randomized Controlled Trial / Moderate High evidenceTwo-week RCT of 61 Parkinson's patients found no significant motor benefit from high-CBD/low-THC cannabis extract vs. placebo, with possible worsening of cognition and sleep.
2024 / Animal Study / Preliminary evidenceCBD rescued memory deficits in Fragile X model rats through hippocampal GPR55 receptors, pointing to a specific mechanism for cognitive benefits in neurodevelopmental disorders.
2024 / Randomized Controlled Trial / Moderate evidenceA placebo-controlled trial found that a single dose of a high-CBD medicinal cannabis oil mildly impaired some memory tasks while improving mood in 31 healthy adults.
2024 / Case Report / Preliminary evidenceA woman with a rare genetic epilepsy experienced major improvements in seizures, sleep, mood, language, and motor skills after starting off-label CBD treatment.
2024 / Narrative Review / Preliminary evidenceLab and animal studies show CBD may protect against Alzheimer's-related neurodegeneration, but no controlled human trials have been conducted.
2024 / Observational / Preliminary evidenceLab tests showed THC/THCA-dominant cannabis extracts protected brain cells from Alzheimer's-related amyloid-beta toxicity, but not by preventing plaque formation.
2024 / Review / Preliminary evidenceA review found CBD shows anti-cancer properties through multiple molecular pathways that trigger cancer cell death.
2024 / Review / Preliminary evidenceWhile CBD works for several genetic epilepsies, evidence for CDKL5 Deficiency Disorder remains largely anecdotal.
2024 / Observational / Preliminary evidenceCBD-dominant cannabis extract improved communication, attention, and behavior while reducing aggression in 30 children with moderate-severe autism.
2024 / Randomized Controlled Trial / Moderate evidenceA placebo-controlled trial found 150mg CBD had no effect on mood, enjoyment, pain, or performance during a 10km run.
2024 / Narrative Review / Moderate evidenceNarrative review finds strongest evidence for THC-based medical cannabis in chronic neuropathic pain and balanced THC/CBD products for MS spasticity, with manageable side effects and low dependence risk.
2024 / Narrative Review / Moderate evidenceReview finds natural cannabinoids may protect kidneys through CB2 activation and help prevent stones, while synthetic cannabinoids pose serious acute kidney injury risk.
2024 / Review / Moderate evidenceReview finds CBD shows strong preclinical promise for gut and lung diseases, but its poor absorption and metabolism create a major gap between lab results and real-world clinical outcomes.
2024 / Systematic Review / Strong evidenceEvidence map of 194 studies found medical cannabis showed positive effects in 57% of treatment descriptions across 71 health outcomes, with strongest support for pain, seizures, and spasticity.
2024 / Animal Study / Moderate evidenceA non-euphoric cannabis extract reduced inflammatory pain in rats without the behavioral impairment caused by THC or synthetic cannabinoids, supporting the entourage effect.
2024 / Systematic Review / Moderate evidenceSystematic review found 31 documented cases of serious drug interactions between cannabis and narrow-therapeutic-index medications — likely a vast undercount of the true burden.
2024 / Narrative Review / Preliminary evidenceReview examines cannabinoids' disease-modification potential in MS and nano-cannabinoid drug delivery.
2024 / Randomized Controlled Trial / Strong evidenceCrossover trial: THC increased attentional bias toward cannabis cues; CBD at three doses did not help.
2024 / Narrative Review / Preliminary evidenceReview of 170 articles maps CBD's neuroprotective mechanisms across brain disorders.
2024 / Animal Study / Preliminary evidenceLab experiments showed CBD shifted immune responses in psoriasis patients' blood cells from inflammatory to anti-inflammatory across multiple immune cell types.
2024 / Review / Preliminary evidenceReview finds CBD shows promise for autism through endocannabinoid system interaction, gut-brain modulation, and a favorable safety profile, though evidence is still preliminary.
2024 / Retrospective Cohort / Moderate evidencePharmaceutical CBD helped about 25-29% of adults with various drug-resistant epilepsies in French epilepsy centers, with no difference in response between epilepsy types.
2024 / Narrative Review / Preliminary evidenceReview of preclinical evidence suggests cannabinoids, especially CBD, could help manage pain, inflammation, and tissue damage after open-heart surgery.
2024 / Animal Study / Preliminary evidenceCBD promoted heart cell regeneration and reduced heart attack damage in mice by downregulating miR-143-3p through the CB2 receptor, restimulating cardiomyocyte proliferation.
2024 / Retrospective Cohort / Moderate evidencePurified CBD as add-on therapy achieved >50% spasm reduction in 68% of 28 infants with treatment-resistant epileptic spasms, with particularly strong responses in Down syndrome patients.
2024 / Case Report / Preliminary evidenceFive of 6 patients with drug-resistant epilepsy from rare GPI-anchored protein deficiencies achieved >=50% seizure reduction with add-on CBD over a median 27-month treatment period.
2024 / Animal Study / Preliminary evidenceA full-spectrum cannabis extract significantly reduced brain cell inflammation and protected neurons from damage in lab models, outperforming CBD alone.
2024 / Randomized Controlled Trial / Preliminary evidenceIn a crossover trial, CBD improved Theory of Mind vs placebo while THC reduced cognitive empathy vs CBD in 18 chronic cannabis users, the first evidence that CBD enhances social cognition.
2024 / Animal Study / Preliminary evidenceMouse study found CBD dose-dependently reduced gastrointestinal symptoms of opioid withdrawal, with consistent effects across both sexes during precipitated withdrawal.
2024 / Animal Study / Preliminary evidenceCBD improved social deficits (at 20 mg/kg) and reduced repetitive behaviors and hyperactivity (at 50 mg/kg) in a mouse model of autism, suggesting dose-dependent targeting of different symptoms.
2024 / Review / Strong evidenceDutch economic analysis found pharmaceutical CBD is cost-effective for Lennox-Gastaut syndrome (21,493 euros/QALY) and cost-saving for Dravet syndrome, supporting reimbursement decisions.
2024 / Randomized Controlled Trial / Strong evidenceRandomized controlled trial found CBD-rich cannabis extract significantly improved social interaction, anxiety, and agitation in 60 children with autism over 12 weeks, with minimal side effects.
2024 / Scoping Review / Moderate evidenceCritical review found the cannabis "entourage effect," widely promoted in marketing, lacks strong scientific evidence as a stable and predictable phenomenon, cautioning against premature acceptance.
2024 / Animal Study / Preliminary evidenceLab study found CBD, CBN, and hemp extract did not harm human liver cells at consumer-relevant doses, though hemp extract showed modest effects on liver function markers at the highest concentration.
2024 / Animal Study / Preliminary evidenceCBGA was the most potent cannabinoid at blocking TRPM7 ion channels, which are involved in cancer, stroke, and kidney disease, working through the channel's kinase domain.
2024 / Review / Moderate evidenceReview of preclinical evidence finds multiple non-intoxicating cannabinoids beyond CBD can reduce gut pain and inflammation through TRP and ion channels, not just classical cannabinoid receptors.
2024 / Animal Study / Preliminary evidenceBlinded lab study found CBD and THC suppressed both pro-inflammatory Th17 cells and regulatory T cells in human immune cells, representing broad immunomodulation rather than simple anti-inflammatory action.
2024 / Animal Study / Preliminary evidencePrenatal CBD oil (THC-free) prevented autism-like behaviors in all three core symptom domains in male rat offspring from a neuroinflammation-based ASD model.
2024 / Animal Study / Preliminary evidenceMouse colitis study found CB2 agonist HU308 matched high-dose CBD efficacy at 1/24th the dose, with both normalizing gut inflammation and GLP-1 hormone levels.
2024 / Pilot Study / Preliminary evidenceSmall feasibility trial found CBD-dominant cannabis oil was safe and well-tolerated over 21 weeks in 12 long COVID patients, with no serious adverse events and 100% adherence.
2024 / Retrospective Cohort / Moderate evidenceMulticenter Israeli study found purified CBD reduced seizures in 92% of 139 children with drug-resistant epilepsy, with 41% achieving >50% reduction and prior CBD oil response predicting success.
2024 / Animal Study / Preliminary evidenceRat study found prenatal CBD exposure caused glucose intolerance in male offspring by 3 months, with altered liver circadian clock and metabolic gene expression, despite no effects at birth.
2024 / Animal Study / Preliminary evidenceInhaled cannabis terpenes linalool and beta-myrcene reduced anxiety in mice, but effective dosing patterns and CBD synergy differed between males and females.
2024 / Observational / Preliminary evidenceCBD reduced the cancer-killing ability of activated NK cells against tumors with high Hsp70 expression by suppressing key immune mediators like interferon-gamma and granzyme B.
2024 / Review / Preliminary evidenceReview of preclinical research finds CBD extends healthspan and lifespan in model organisms through autophagy and antioxidant mechanisms, with emerging evidence against cellular senescence.
2024 / Randomized Controlled Trial / Preliminary evidenceSmall 16-day RCT found no significant CBD effect on seborrheic dermatitis in Parkinson's patients, though trends favored CBD over placebo (p = .07 between groups).
2024 / Review / Moderate evidenceExpert panel developed practical consensus guidelines for optimizing Epidiolex dosing in rare epilepsies, emphasizing individualized titration, drug interaction management, and distinguishing from non-approved CBD products.
2024 / Cross Sectional / Preliminary evidencePET imaging shows cannabis users with trauma have 15-20% higher mGlu5 glutamate receptors in frontal and limbic brain regions — a molecular link between the endocannabinoid and glutamate systems.
2024 / Animal Study / Preliminary evidenceSynthetic CBD analogue H4CBD reduced body mass by 15% and improved glucose response by 29% in aged diabetic rats, primarily through abdominal fat loss rather than changes in insulin signaling.
2024 / Review / Moderate evidenceUpdated risk assessment establishes a 10 mg/day health-based guidance value for CBD in food products, based on liver toxicity data from both animal and human studies.
2024 / Systematic Review / Moderate evidenceReview of 14 randomized trials found CBD improved anxiety and cognition in 9 of 16 outcomes, with oral doses of 200-1,500 mg showing efficacy and a good safety profile.
2025 / Pilot Study / Preliminary evidencePilot trial of oral CBD after tooth extraction (n=8) established that the trial protocol is feasible — setting up a larger study to determine whether CBD actually works for dental pain.
2025 / Retrospective Cohort / Moderate evidenceMulticenter retrospective study found CBD as add-on therapy reduced median monthly seizures from 30 to 8 across multiple drug-resistant epilepsy types in children.
2025 / Longitudinal Cohort / Moderate evidenceNational ABCD Study of 2,262 adolescents found hair cannabinoid levels predicted sex-specific changes in sleep, exercise, and mental health outcomes a year later.
2025 / Randomized Controlled Trial / Preliminary evidenceFeasibility RCT found nabiximols oral spray was safe and well-tolerated for agitation in 29 Alzheimer's nursing home residents, with zero adverse reactions.
2025 / Animal Study / Preliminary evidenceMouse study found CBD oil improved autistic behaviors and reduced brain oxidative stress comparably to risperidone in a valproic acid-induced autism model.
2025 / Observational / Preliminary evidenceReddit analysis of 63.5 million posts found users reporting previously undocumented drug interactions between consumer cannabis products and immunosuppressants.
2025 / Systematic Review / Moderate evidenceSystematic review of 22 RCTs found cannabis-based medicines reduced neuropathic pain in 68% of trials, with better outcomes using personalized dosing strategies.
2025 / Animal Study / Preliminary evidenceMouse study found combining CBD and beta-caryophyllene produced synergistic pain relief with antidepressant effects through reduced neuroinflammation.
2025 / Animal Study / Preliminary evidenceRat study found CBD prevented morphine-induced pain hypersensitivity in both sexes and partially reduced withdrawal symptoms, with sex-dependent response patterns.
2025 / Animal Study / Preliminary evidenceMouse study found cannabigerol (CBG) had no effect on fear memory at any dose tested, though females showed an unusual biphasic pain response.
2025 / Observational / Preliminary evidenceHigh-CBD extract reduced inflammatory cytokines from human immune cells and lessened arthritis severity in two mouse models of RA — the most complete preclinical package yet for cannabinoids in rheumatoid arthritis.
2025 / Case Report / Preliminary evidenceCase report of a 31-year-old with no psychiatric history who developed a manic episode after three months of escalating high-dose CBD vaping, resolving after discontinuation.
2025 / Animal Study / Preliminary evidenceThree weeks of THC-CBD treatment did not improve Alzheimer's-related deficits in transgenic mice and produced genotype-dependent effects on anxiety.
2025 / Animal Study / Preliminary evidencePrenatal CBD exposure in rats reduced birth weight and altered early neurodevelopmental behaviors at higher doses, though differences resolved by weaning.
2025 / Animal Study / Preliminary evidenceCBD dose-dependently reduced binge-like alcohol drinking in mice, with the effect maintained over repeated dosing and evidence pointing to a novel neuropeptide S receptor mechanism.
2025 / Case Report / Preliminary evidenceCase report of a 45-year-old woman who developed liver injury while using cannabis oil, with improvement after discontinuation, highlighting CBD as a potential hepatotoxin.
2025 / Animal Study / Preliminary evidenceA non-psychoactive cannabis extract reduced cocaine preference extinction time and blocked priming-dose relapse in mice, with serotonin receptors mediating the effect.
2025 / Pilot Study / Preliminary evidence300 mg CBD increased feelings of calm and relaxation before a 2-mile run but had no effect on running speed, heart rate, or other performance measures in 12 runners.
2025 / Randomized Controlled Trial / Strong evidenceDouble-blind RCT found 50 mg CBD enhanced opioid pain relief and reduced psychomotor impairment without additional side effects, suggesting opioid-sparing potential.
2025 / Randomized Controlled Trial / Moderate evidenceInterim analysis of 240 children with Fragile X syndrome found transdermal CBD gel was safe over 28 months with mild side effects and encouraging behavioral improvements.
2025 / Animal Study / Preliminary evidenceChronic nicotine pouch exposure worsened seizures and brain inflammation in mice, but inhaled CBD reversed these effects by restoring brain waste clearance and reducing inflammatory markers.
2025 / Animal Study / Preliminary evidenceMouse study found cannabidiolic acid (CBDA) reached plasma levels roughly 100 times higher than CBD at the same dose, suggesting the acid form may be far more bioavailable.
2025 / Animal Study / Preliminary evidenceDaily CBD reversed more than 75% of over 1,000 Alzheimer's-related molecular changes in a mouse model, affecting pathways from inflammation to synaptic plasticity.
2025 / Animal Study / Preliminary evidenceCBD treatment reduced pro-death cell signaling and restored glial cell populations in the brains of adult rat offspring born to obese mothers.
2025 / Animal Study / Preliminary evidenceRat study found smoked cannabis during pregnancy produced different and generally milder offspring behavioral changes than injected THC or CBD, with some effects resolving by adulthood.
2025 / Observational / Preliminary evidenceIn lab tests, a CBD-rich cannabis extract suppressed T cell activation and inflammatory markers more potently than dexamethasone or tacrolimus, two standard immunosuppressants.
2025 / Animal Study / Preliminary evidenceA very low dose of CBD (1 mg/kg) partially reversed stress-induced behavioral changes in mice and completely restored mature synapse formation in the prefrontal cortex.
2025 / Animal Study / Preliminary evidenceRat study found combining CBD with sub-therapeutic buprenorphine produced significant pain relief while CBD also reduced buprenorphine-induced respiratory depression, suggesting a safer analgesic approach.
2025 / Retrospective Cohort / Preliminary evidenceRetrospective study of 15 children with drug-resistant epilepsy found CBD reduced seizures in 11 (2 seizure-free), with improved social participation and a good safety profile, including off-label use.
2025 / Retrospective Cohort / Moderate evidenceFive-year monitoring of 38 children on pharmaceutical CBD found zero detectable THC in blood at any timepoint, with CBD levels rising predictably with dose.
2025 / Meta Analysis / Strong evidenceMeta-analysis of 13 clinical studies found CBD and THC had trivial, non-significant effects on blood inflammatory markers (IL-6, IL-8, IL-10, TNF-alpha), with evidence certainty ranging from very low to moderate.
2025 / Animal Study / Preliminary evidenceCBD reduced brain inflammation and improved neurological outcomes after traumatic brain injury in rats by acting through the PGE2-EP2-cAMP-PKA signaling pathway.
2025 / Animal Study / Preliminary evidenceIn morphine-dependent monkeys, THC modestly reduced some withdrawal signs but was not more effective than existing medication lofexidine, while CBD had no effect alone or combined with THC.
2025 / Animal Study / Preliminary evidenceDaily CBD given to young mice from weaning reduced Sertoli cells during spermatogenesis and lowered sperm viability and morphology after 34 days.
2025 / Retrospective Cohort / Strong evidenceMulticenter study of 266 patients with 77 different genetic epilepsies found nearly half achieved 50%+ seizure reduction with CBD, with comparable effectiveness between approved and off-label uses.
2025 / Animal Study / Preliminary evidenceMouse study found CBD dampens seizure-like hippocampal activity spread by boosting fast-acting inhibitory PV interneurons through GPR55 receptor signaling.
2025 / Review / Preliminary evidenceReview of case reports and 9,142 FDA adverse event reports identified potential cannabis-drug interactions in children, particularly involving enzyme inhibition of methadone, everolimus, and antidepressants.
2025 / Prospective Cohort / Strong evidenceProspective study of 103 children with drug-resistant epilepsy found over half responded to CBD, with sustained seizure and non-seizure benefits and 55% retention at 18 months.
2025 / Animal Study / Preliminary evidenceMouse study found CBD improved treadmill endurance by reshaping gut microbiome; the effect required intact gut bacteria and was reproduced by a single CBD-enriched bacterial species.
2025 / Randomized Controlled Trial / Strong evidenceCrossover RCT found CBD pre-treatment (1000mg) worsened cannabis-induced memory impairment and psychotic symptoms in 30 patients with schizophrenia, contradicting the protective hypothesis.
2025 / Systematic Review / Strong evidenceLiving systematic review of 276 studies found most evidence for pediatric cannabinoids is for epilepsy, with CBD showing 30-50% seizure reduction in RCTs.
2025 / Animal Study / Preliminary evidenceSingle vaporized THC exposure suppressed hippocampal dopamine receptor genes and upregulated glutamate genes in mice, with most recovering within 14 days except persistent Adcy5 downregulation.
2025 / Animal Study / Preliminary evidenceMouse study found that CBD exposure during pregnancy or nursing decreased pup survival and caused lasting sex-dependent changes in behavior and metabolism.
2025 / Animal Study / Preliminary evidenceIn a zebrafish autism model, CBD reversed hyperactivity and aggression more effectively than risperidone and normalized underlying neurobiological markers.
2025 / Narrative Review / Preliminary evidenceParents are increasingly giving children unregulated CBD products despite FDA approval only for specific epilepsy — with concerns about product quality, drug interactions, and absent pediatric evidence.
2025 / Randomized Controlled Trial / Moderate evidenceLongest cannabinoid trial in Alzheimer's: 26 weeks of very low-dose THC-CBD extract showed significantly higher cognitive scores vs placebo.
2025 / Cross Sectional / Moderate evidenceSurvey of 1,721 medical cannabis patients shows widespread use of delta-8 THC, THCA, CBG, and CBN. Most reported stopping at least one pharmaceutical.
2025 / Animal Study / Preliminary evidenceIn rat migraine models, CBD combined with 0.3% THC provided the longest pain relief and was the only treatment reducing light sensitivity.
2025 / Meta Analysis / Moderate evidenceMeta-analysis of 6 RCTs (1,077 patients): cannabinoids improve sleep quality, but the effect is driven by non-CBD formulations. CBD alone showed no benefit.
2025 / Animal Study / Moderate evidenceRat study: CBD accelerated extinction of meth-seeking behavior and prevented relapse. Both effects required D1 dopamine receptors in the hippocampal dentate gyrus.
2025 / Observational / Preliminary evidenceOpen-label study: CBD-rich cannabis for autistic children reduced family accommodation burden and parental distress at 3 and 6 months.
2025 / Observational / Preliminary evidence65 autistic children on CBD-rich cannabis for 6 months: reduced anxiety and repetitive behaviors. Anxiety reduction predicted subsequent behavior improvement.
2025 / Systematic Review / Preliminary evidenceA systematic review of 7 clinical studies found topical CBD showed promise for oral pain, gum inflammation, and mouth sores with no serious side effects, though evidence remains preliminary due to small study sizes and varying methods.
2025 / Animal Study / Preliminary evidenceCBD reduced nerve pain in mice through a mechanism involving peripheral mu and delta opioid receptors, suggesting it may engage the body's own pain-relief pathways without being an opioid itself.
2025 / Animal Study / Preliminary evidenceNanoemulsion-delivered CBD, THC, and their combinations reduced seizures and brain oxidative stress in mice, with low-dose combinations matching the anticonvulsant drug valproic acid in delaying seizure progression.
2025 / Systematic Review / Moderate evidenceA systematic review of 49 controlled studies across 11 mental health diagnoses found CBD may offer short-term anxiety relief and CBD/THC combinations helped with cannabis withdrawal and sleep, but THC worsened psychosis and no long-lasting benefits were found for any product.
2025 / Animal Study / Preliminary evidenceNanoencapsulated CBD reduced panic-like responses in mice confronted by a venomous snake at much lower doses than standard CBD, with confirmed delivery to fear-processing brain regions via both injection and nasal routes.
2025 / Animal Study / Preliminary evidenceA rat study comparing five cannabis oils found THC-rich formulations best reduced liver fat and damage while CBD-rich oils better lowered blood pressure, with 1:1 and 2:1 CBD:THC ratios offering benefits across multiple metabolic syndrome features.
2025 / Animal Study / Preliminary evidenceA 90-day rat safety study of CBD-rich hemp extract found no organ damage or behavioral changes at doses up to 35 mg/kg/day, but detected sex-dependent kidney and liver biomarker shifts, with CBD accumulating most in muscle, skin, and kidneys.
2025 / Animal Study / Preliminary evidenceA cannabis extract with equal parts CBD and THC reduced neuroinflammation, prevented tissue damage expansion, and improved movement recovery in rats after spinal cord injury, working across both acute and chronic phases.
2025 / Case Report / Preliminary evidenceTwo patients with life-threatening status epilepticus that failed standard treatments achieved seizure resolution after adding highly purified CBD via nasogastric tube, with continued benefit at 6 months and no adverse events.
2025 / Observational / Preliminary evidenceCBN reduced pro-inflammatory cytokines and increased anti-inflammatory markers in human skin cells, with the key finding that its reduction of itch-associated IL-31 was mediated specifically through TRPV1 receptors.
2025 / Observational / Preliminary evidenceCBD treatment of chronic myeloid leukemia cells triggered over 3,400 gene expression changes at both 4 and 12 hours, affecting oxidative stress, p53-mediated cell death, immune signaling, and metabolic pathways.
2025 / Animal Study / Preliminary evidenceChronic CBD treatment increased brain copper in healthy female mice but not in Alzheimer's model mice, disrupting the coordinated regulation of metals across brain regions in the disease model, suggesting CBD's brain effects differ between healthy and diseased states.
2025 / Animal Study / Preliminary evidenceCBD selectively induced beneficial cell death in amyloid-beta-expressing cells while causing side effects in healthy cells, with FAAH involvement helping to rescue dysfunction in amyloid-expressing worm models, revealing context-dependent effects.
2025 / Pilot Study / Preliminary evidenceThe first trial of medicinal cannabis in teenagers with Tourette syndrome found significant improvements in tics, behavior, and quality of life, with tiredness as the most common side effect.
2025 / Randomized Controlled Trial / Preliminary evidenceThe first placebo-controlled trial of medicinal cannabis for Tourette syndrome in teenagers found the protocol was feasible, with some signal of benefit and dizziness as the most common side effect.
2025 / Randomized Controlled Trial / Moderate evidenceA controlled study found raw cannabinoids (CBDA, THCA) achieved 19-25x higher blood levels than activated forms (CBD, THC), and even 7.2mg of THC in a full-spectrum product caused noticeable intoxication.
2025 / Animal Study / Preliminary evidenceCombining CBD-rich cannabis oil with omega-3 fish oil prevented nerve pain and protected against nerve damage in rats, suggesting a potential combination therapy for neuropathic pain.
2025 / Retrospective Cohort / Moderate evidenceA UK early access program found pharmaceutical CBD reduced motor seizures by a median 60% at 12 months in 26 children with Lennox-Gastaut or Dravet syndrome, with 67% achieving at least 50% improvement.
2025 / Animal Study / Preliminary evidenceIn Alzheimer's mice, inhaled CBD reduced two key neuroinflammation pathways (IDO and cGAS) and lowered proinflammatory cytokines, suggesting a multi-target anti-inflammatory mechanism.
2025 / Review / Moderate evidenceGermany's food safety commission found CBD supplement doses on the market can reach levels causing liver enzyme changes (4.3 mg/kg/day), while no health benefit claims were supported at any tested dose.
2025 / Animal Study / Preliminary evidenceCBD activated cellular autophagy and reduced alpha-synuclein levels in neuroblastoma cells through CB1 receptor signaling, suggesting a mechanism relevant to Parkinson's disease.
2025 / Animal Study / Preliminary evidenceCBD protected nerve cells from a Parkinson's-relevant toxin by activating the Nrf2 antioxidant pathway, reducing oxidative stress, and preventing cell death in culture.
2025 / Systematic Review / Preliminary evidenceA systematic review found CBD targets pancreatic cancer through multiple mechanisms and enhances chemotherapy in lab studies, but no clinical trials have been conducted.
2025 / Systematic Review / Preliminary evidenceA systematic review of 19 studies found CBD killed lung cancer cells through multiple pathways, inhibited metastasis, boosted immune response, and enhanced cisplatin and radiation effectiveness.
2025 / Systematic Review / Preliminary evidenceA review of 16 studies found CBD fought liver cancer through multiple mechanisms including a specific inflammatory cell death pathway, and enhanced the effectiveness of standard drugs sorafenib and cabozantinib.
2025 / Systematic Review / Preliminary evidenceA systematic review found CBD fights gastrointestinal cancers through multiple mechanisms including cell death induction, growth inhibition, and potential enhancement of conventional chemotherapy.
2025 / Randomized Controlled Trial / Preliminary evidenceA pilot RCT found 4 weeks of low-dose CBD (60mg/day) did not improve blood sugar control, gut microbiome composition, or inflammation in 16 overweight or obese adults.
2025 / Animal Study / Preliminary evidenceCBD reversed elevated dopamine neuron activity in both male and female rats in a schizophrenia model and corrected memory deficits in males.
2025 / Animal Study / Preliminary evidenceA nano-formulated CBD preparation fully suppressed neuropathic pain in mice with a single dose by selectively quieting overactive pain circuits.
2025 / Pilot Study / Preliminary evidencePhase 2 trial found CBD reduced aromatase inhibitor joint pain in 44% of breast cancer patients, with an average 2.36-point improvement among completers.
2025 / Cross Sectional / Preliminary evidenceSurvey found nearly half of breast cancer patients used CBD, mainly for pain and insomnia, with mixed self-reported results.
2025 / Randomized Controlled Trial / Strong evidenceFDA trial found 5.6% of healthy adults on consumer-level CBD doses developed significant liver enzyme elevations in 28 days.
2025 / Cross Sectional / Moderate evidenceEuropean survey of 35,789 cannabis users found 42% also used CBD for similar reasons.
2025 / Animal Study / Moderate evidenceCBD treatment preserved heart function in mice with heart failure by maintaining mitochondrial function and calcium handling through PPARgamma receptors.
2025 / Animal Study / Moderate evidenceCBDA was the most effective of five cannabinoids tested in ALS mice, outperforming standard medication riluzole in preserving motor neurons and shifting brain immune cells toward an anti-inflammatory state.
2025 / Animal Study / Preliminary evidenceCBD inhibited EGFR signaling in triple-negative breast cancer cells and doubled their susceptibility to natural killer cell attack by upregulating the FAS death receptor.
2025 / Animal Study / Moderate evidenceA CBD:CBDV combination reduced colitis in mice by suppressing immune cell trafficking through CB2 receptors, providing mechanistic evidence for the entourage effect.
2025 / Cross Sectional / Moderate evidenceNearly 70% of CBD users in an ED survey were taking prescription medications with known drug interaction potential, primarily antidepressants and blood pressure medications.
2025 / Animal Study / Moderate evidenceCBD reshaped gut bacteria in arthritic rats, boosting butyric acid and L-carnitine levels that reduced inflammation in immune cells and joint tissue.
2025 / Observational / Moderate evidenceIn 751 cancer patients with chemotherapy-induced neuropathy, THC-dominant cannabis products produced significantly better symptom relief, daily functioning, and quality of life than CBD-dominant products.
2025 / Animal Study / Moderate evidenceOral CBD delayed disease progression (by weight) and improved specific cognitive and social deficits in ALS mice in a sex-dependent manner, but did not rescue motor function.
2025 / Animal Study / Preliminary evidenceOral hemp extract high in CBG and CBD reduced colonic damage and pain in a mouse ulcerative colitis model, supporting further investigation of cannabinoid combinations for IBD.
2025 / Review / Preliminary evidenceLiterature review finds CBD showed anti-inflammatory and anti-angiogenic effects in experimental endometriosis models, but human clinical evidence for cannabinoid treatment of endometriosis is essentially absent.
2025 / Animal Study / Preliminary evidenceFive cannabinoids (THC, CBD, THCV, CBC, CBG) protected insulin-producing cells from metabolic stress-induced death, with most also preserving cell function, suggesting potential relevance for type 2 diabetes.
2025 / Cross Sectional / Preliminary evidenceSurvey of 261 women found widespread uncertainty about cannabis and CBD risks during pregnancy, with no difference between pregnant and non-pregnant respondents.
2025 / Animal Study / Preliminary evidenceAlzheimer's model mice given daily CBD for two months showed improved memory, less anxiety, and reduced brain oxidative stress.
2025 / Clinical Trial / Moderate evidenceA single 30 mg CBD dose increased amitriptyline blood levels by 13% in healthy volunteers, demonstrating drug interaction potential even at low doses.
2025 / Retrospective Cohort / Moderate evidenceAmong 50 children with drug-resistant epilepsy treated with CBD for at least six months, 56% had meaningful seizure reduction and 16% became seizure-free.
2025 / Observational Study / Preliminary evidenceProspective study of 16 children with severe autism found CBD-rich extract reduced internalizing behaviors after three months, with caregivers also reporting improved mental health.
2025 / Cross Sectional / Preliminary evidenceSurvey of 84 youth in mood disorder treatment and 66 parents found most believe cannabis and CBD effectively treat mental health conditions.
2025 / Clinical Trial / Preliminary evidencePilot trial of 12 women found oral cannabis capsules (100 mg CBD/5 mg THC TID) did not outperform placebo for chemotherapy-induced nerve pain.
2025 / Clinical Trial / Preliminary evidenceSmall crossover trial found a low-dose cannabinoid supplement (3 mg THC, 6 mg CBN, 10 mg CBD) improved sleep quality and insomnia symptoms vs placebo over 10 days.
2025 / Animal Study / Preliminary evidenceResearchers created CBD-like molecules from spearmint compounds that showed stronger anti-seizure effects than natural CBD in mouse models of epilepsy.
2025 / Retrospective Cohort / Moderate evidenceOff-label CBD treatment across 108 patients with various refractory epilepsies achieved 38.9% responder rate at three months, with tolerability similar to approved indications.
2025 / Cross Sectional Survey / Low evidenceAnonymous survey found chronic pain sufferers using CBD isolate reported decreased pain at low doses with minimal side effects, though the design limits conclusions.
2025 / Animal Study / Low evidenceMouse study found CBD reduced stress-induced liver damage by activating CB2 receptors and protective antioxidant pathways, improving inflammation, fibrosis, and mitochondrial health.
2025 / Randomized Controlled Trial / Moderate evidenceCrossover trial found CBD normalized glutathione, glutamate, and GABA levels in AUD participants who drank the day before, but had no effect in those who abstained.
2025 / Randomized Controlled Trial / Moderate evidenceCrossover fMRI trial found 800 mg CBD reduced precuneus activation during alcohol cue exposure in AUD participants, though craving and mood were unaffected.
2025 / Animal Study / Low evidenceMouse study found CBD-rich cannabis extract was more effective than pure synthetic CBD against brain inflammation, reducing anxiety, cognitive deficits, and oxidative stress.
2025 / Randomized Controlled Trial / Moderate evidenceCrossover RCT found 60 mg/day CBD for 7 days blunted exercise-induced liver enzyme elevations in athletes without hepatotoxicity, with medium-to-large effect sizes.
2025 / Cross Sectional Survey / Low evidenceSurvey of 918 hand surgery patients found 15% had tried CBD, with only 39% of users reporting pain relief. CBD users had higher pain scores and worse function.
2025 / Preclinical Study / Low evidenceZebrafish epilepsy model found cannabis extracts matched pure CBD for seizure reduction despite containing much less CBD, supporting an entourage effect.
2025 / Animal Study / Low evidenceAged obese rats given CBD showed reduced anxiety, lower circulating endotoxin, and decreased brain inflammation markers, with disrupted endocannabinoid signaling partially restored.
2025 / Animal Study / Low evidenceRat study found oral THC provided dose-dependent inflammatory pain relief (stronger in females), but adding CBD diminished THC's analgesic effects rather than enhancing them.
2025 / Meta Analysis / Moderate evidenceMeta-analysis found people with autism had significantly lower blood anandamide levels, and animal models showed reduced brain endocannabinoids, with symptom improvement when levels were raised.
2025 / Animal Study / Low evidenceIn a rat PTSD model, CBD did not significantly reduce anxiety but improved spatial memory and reduced brain oxidative stress, suggesting neuroprotective rather than directly anxiolytic effects.
2025 / Laboratory Analysis / Moderate evidenceLab analysis of 80 CBD products found all contained CBDV, most contained CBG, CBC, CBN, and CBDA at widely varying concentrations not disclosed on labels.
2025 / Cross Sectional Survey / Low evidenceA survey of 80 elite Canadian athletes found 38% had used CBD, with most reporting benefits for sleep (93%) and relaxation (90%). Anti-doping violation concerns were the top barrier to use.
2025 / Narrative Review / Preliminary evidenceAbout 30% of epilepsy patients resist standard drugs—and the evidence for CBD and THC as anticonvulsants keeps growing, though access remains limited.
2025 / Open Label Clinical Trial / Low evidenceAn open-label trial of 11 girls with Rett syndrome found a low-THC cannabis extract improved communication, eye contact, attention, anxiety, and quality of life over 12 weeks.
2025 / Preclinical Study / Low evidenceCBG suppressed key inflammatory markers and pathways (MAPK, NF-kB) in cell cultures and a mouse model, though physical inflammation reduction in mice was not statistically significant.
2025 / Preclinical Study / Low evidenceCBD blocked metastasis-promoting EMT in pancreatic cancer cells by inhibiting the lncRNA MALAT1 and PI3K/Akt/mTOR signaling, and synergized with gemcitabine chemotherapy in 3D tumor models.
2025 / Randomized Controlled Trial / Moderate evidenceA placebo-controlled trial of 36 youth with alcohol use disorder found single-dose 600mg CBD had no effect on brain chemistry, alcohol cue-reactivity, cravings, or drinking behavior.
2025 / Animal Study / Preliminary evidenceIn mouse meningeal preparations, anandamide showed stronger suppression of pain-related firing than 2-AG, pointing to FAAH inhibition as a migraine target.
2025 / Cross Sectional / Moderate evidenceA German survey of 702 CBD users found 38% self-medicate for sleep, pain, depression, and anxiety, with older and unemployed individuals most likely.
2025 / Animal Study / Preliminary evidenceIn mice, FAAH inhibition reduced anxiety while CB1 blockade and CB2 manipulation increased it.
2025 / Observational / Preliminary evidenceCBG relaxes human pulmonary arteries through endothelium-dependent mechanisms, modified by hypertension and high cholesterol.
2025 / Randomized Controlled Trial / Strong evidenceCBD raised anandamide but this did not correlate with blood pressure reduction in 66 hypertensive patients.
2025 / Observational / Preliminary evidenceOf five cannabinoids tested against MRSA biofilms, CBN was most effective at reducing biomass and viability, while each cannabinoid showed a different mechanism of action.
2025 / Animal Study / Preliminary evidenceCBD nanoparticles restored gut barrier function, reduced inflammation, and normalized metabolites in stressed rats, performing comparably to standard antidepressants.
2025 / Retrospective Cohort / Moderate evidenceAnalysis of 130 cannabinoid-related seizure reports found 68% of individuals had pre-existing risk factors, with drug interactions the most common contributor.
2025 / Cross Sectional / Preliminary evidencePain clinic patients with nerve pain used THC/CBD products more frequently than those with other pain types—possibly reflecting a gap in conventional treatment.
2025 / Observational / Preliminary evidenceCBD and its metabolites reduced human neural stem cell viability at clinically relevant concentrations and altered differentiation markers, raising prenatal safety concerns.
2025 / Meta Analysis / Moderate evidenceA meta-analysis of 26 animal studies found cannabinoids significantly reduced brain damage after stroke, with CBD showing the most consistent benefits across multiple protective pathways.
2025 / Animal Study / Preliminary evidenceCBD protected dopamine neurons and delayed motor symptoms in a progressive Parkinson mouse model, with preventive treatment working better than treatment started after symptom onset.
2025 / Observational / Preliminary evidenceA study of people with anxiety found that baseline inflammation levels influenced whether different cannabis products improved mood and sleep, with CBD-dominant products showing the most reliable benefits.
2025 / Systematic Review / Moderate evidenceAnalysis of 105 datasets found THC and CBD have largely different molecular effects: CBD consistently suppressed inflammation while THC primarily affected neuronal signaling.
2025 / Randomized Controlled Trial / Preliminary evidenceA small controlled trial of THC/CBD capsules found no evidence that cannabinoids reduced essential tremor amplitude, despite widespread anecdotal reports of cannabis helping.
2025 / Review / Moderate evidenceA review found unregulated cannabinoid vaping products contain high concentrations and produce potentially toxic heating byproducts called quinones that may damage lung tissue.
2025 / Animal Study / Preliminary evidenceCBD reduced depression-like symptoms and protected memory in socially isolated mice, but unexpectedly increased anxiety in non-stressed mice, highlighting CBD's context-dependent effects.
2025 / Prospective Cohort / Moderate evidenceA Thai multicenter study found CBD-enriched oil reduced seizures in children who had failed an average of 7 medications, with benefits sustained over 12+ months and mostly mild side effects.
2025 / Animal Study / Preliminary evidenceMouse study found sesame oil delivered far more CBD and THC to tissues than omega-3 oils, and different carriers directed cannabinoids to different organs, with DHA oil favoring the brain.
2025 / Review / Moderate evidenceA review found the endocannabinoid system regulates fear and extinction learning in PTSD, with preliminary evidence that cannabinoid-based treatments like nabilone can help, though self-medication carries risks.
2025 / Randomized Controlled Trial / Moderate evidenceA controlled trial of 42 dogs found CBD/THC extract added to standard painkillers did not improve pain, mobility, or recovery after knee surgery compared to placebo.
2025 / Animal Study / Preliminary evidenceCBD reduced seizures and brain damage in rats with post-traumatic epilepsy by targeting the TRPV1 channel, suggesting a potential preventive treatment for epilepsy after brain injury.
2025 / Animal Study / Preliminary evidenceBrain imaging in rats showed THC increased connectivity and blood flow while CBD decreased connectivity, and combining them produced moderate effects, providing biological evidence for how CBD moderates THC.
2025 / Animal Study / Preliminary evidenceIn a mouse model of pancreatic cancer, CBD alone extended survival and altered gut bacteria and bile acid metabolism, while THC and the THC-CBD combination did not improve outcomes.
2025 / Animal Study / Preliminary evidenceLab study found cannabis extracts containing CBD and CBG were more effective than individual cannabinoids at reducing gut inflammation and restoring intestinal barrier function.
2025 / Narrative Review / Preliminary evidenceReview proposes that cannabinoids interact with extracellular vesicles to create a signaling network relevant to neuropsychiatric disorders, with potential for biomarker-guided personalized treatment.
2025 / Randomized Controlled Trial / Moderate evidenceRandomized study found CBD reduced depression, anxiety, and stress more than THC over 4 weeks in underrepresented groups, with perceived discrimination amplifying the benefit.
2025 / Animal Study / Preliminary evidenceCBD given during repeated social stress in mice prevented social avoidance and enhanced cocaine vulnerability while normalizing serotonin, endocannabinoid, and stress hormone gene expression.
2025 / Animal Study / Preliminary evidenceLab study provides first evidence that CBD suppresses HLA-G, a molecule tumors use to hide from the immune system, in choriocarcinoma cells.
2025 / Randomized Controlled Trial / Preliminary evidenceRandomized study in 40 cats found 2 weeks of CBD reduced fear-related urination during thunderstorm simulations compared to placebo.
2025 / Review / Preliminary evidenceReview finds THC and CBD show multiple anticancer mechanisms against cervical cancer in preclinical studies, with nanotechnology delivery and combination therapies enhancing potential.
2025 / Narrative Review / Preliminary evidenceReview examines the cannabis-ADHD connection, finding elevated cannabis use risk in ADHD and early evidence that CBD may have therapeutic potential through dopamine pathway modulation.
2025 / Randomized Controlled Trial / Preliminary evidencePhase I trial of a CBD-hydroxychloroquine combination for inflammatory conditions showed good tolerability and bioavailability in 36 healthy volunteers.
2025 / Observational / Preliminary evidenceA novel drug delivery technology dramatically improved CBD absorption and brain levels in rats, showing anti-seizure effects at potentially lower doses than Epidiolex.
2025 / Cross Sectional / Preliminary evidenceSurvey finds U.S. parents split on CBD product safety for children, with many unaware of rising pediatric poison control calls.
2025 / Review / Moderate evidenceReview finds CBD targets multiple Alzheimer's pathways in preclinical studies, with computer modeling revealing potential gene targets for future research.
2025 / Review / Preliminary evidenceReview finds THCV, a non-psychoactive cannabinoid, shows promise for appetite suppression and blood sugar regulation in preclinical and early human studies.
2025 / Animal Study / Preliminary evidenceAging mice given oral CBD for 7 months showed reduced brain inflammation and improved cognitive function across multiple brain region-specific tasks.
2025 / Narrative Review / Preliminary evidenceReview finds cannabinoids have properties relevant to dental pain and anxiety, but clinical evidence, standardized protocols, and regulatory clarity are all lacking.
2025 / Randomized Controlled Trial / Moderate evidenceParkinson's RCT finds 26 mg/day CBD was safe but showed limited cognitive benefit beyond naming scores, with the low dose potentially below the therapeutic threshold.
2025 / Randomized Controlled Trial / Moderate evidenceA 60-day double-blind trial found CBD-rich cannabis oil (45 mg/day) did not reduce knee osteoarthritis pain more than placebo.
2025 / Review / Strong evidenceReview maps endocannabinoid system dysregulation in childhood epilepsy and outlines emerging treatment strategies beyond CBD, including allosteric modulators and enzyme inhibitors.
2025 / Observational / Preliminary evidenceCBD selectively killed cervical, breast, and colon cancer cells in the lab while sparing normal cells, with colon cancer cells showing the highest sensitivity.
2025 / Systematic Review / Moderate evidenceSystematic review of 22 studies finds CBD-based products improve pain, seizures, and skin conditions in dogs with no serious side effects, but cat research is minimal.
2025 / Randomized Controlled Trial / Moderate evidenceHuman clinical data shows CBD, but not THC, boosts anti-inflammatory lipid production through the 15-LOX pathway, providing molecular evidence for CBD's therapeutic potential.
2025 / Animal Study / Preliminary evidenceCBD reduced brain inflammation, oxidative stress, and cognitive impairment in rats with liver disease-induced brain dysfunction through multiple anti-inflammatory pathways.
2025 / Randomized Controlled Trial / Moderate evidenceRandomized trial finds CBD improves walking speed and reduces pain in MS patients but does not directly reduce spasticity, suggesting CBD may help through alternative mechanisms.
2025 / Randomized Controlled Trial / Preliminary evidencePilot RCT finds full-spectrum CBD with trace THC reduced alcohol craving in people with AUD, while CBD without THC did not, suggesting the trace THC component matters.
2025 / Narrative Review / Preliminary evidenceCBD modulates immune function through multiple mechanisms with potential for autoimmune diseases, though most evidence remains preclinical. Nanotechnology may improve delivery.
2025 / Randomized Controlled Trial / Preliminary evidenceControlled study finds CBD/CBDA paste effectively reduces arthritis pain in cats, but nearly half dropped out due to refusal to eat the paste, highlighting a formulation challenge.
2025 / Randomized Controlled Trial / Preliminary evidenceA small RCT found that topical CBD plus myrcene gel significantly reduced pain during sex for women with vestibulodynia compared to placebo over 60 days.
2025 / Systematic Review / Preliminary evidenceA systematic review of 18 studies found preclinical promise for cannabinoids in supporting healthy aging, but noted that human evidence remains too sparse to draw definitive conclusions.
2025 / Cross Sectional / Moderate evidenceAn analysis of over 624,000 cannabis products on Leafly and Weedmaps found more than 26,000 listings making health benefit claims, with mood disorders, pain, and sleep being the most common.
2025 / Randomized Controlled Trial / Preliminary evidenceA crossover RCT of 20 healthy adults found that low-dose THC:CBD oils (1:1 and 1:16 ratios) did not cause daytime sleepiness or change night-time sleep compared to placebo.
2025 / Animal Study / Preliminary evidenceCBD reduced involuntary movements caused by Parkinson's medication in rats without diminishing the drug's motor benefits, working through CB1, PPARy receptors, and endocannabinoid pathways.
2025 / Animal Study / Preliminary evidenceChronic CBD from weaning reversed anxiety, brain molecular changes, gut microbiota dysbiosis, and increased alcohol motivation in mice with fetal alcohol exposure, with effects varying by sex.
2025 / Narrative Review / Moderate evidenceA practical clinical guide to prescribing pharmaceutical CBD for drug-resistant epilepsy—covering dosing strategies, drug interactions, and the 'start low, go slow' approach.
2025 / Animal Study / Preliminary evidenceAmong multiple cannabinoid treatments tested in sleep-deprived mice, a CBD+CBC combination was the most effective at reversing memory impairment, depression, and brain inflammation.
2025 / Randomized Controlled Trial / Preliminary evidenceA triple-blind crossover trial of 17 older adults with poor appetite found that a THC/CBD mouth spray did not increase caloric intake compared to placebo, though it was well tolerated.
2025 / Qualitative / Preliminary evidenceA qualitative study of 24 Greeks found CBD-experienced patients reported benefits for pain and anxiety but wanted better guidance, while cannabis-naive patients were skeptical but open to regulated medical use.
2025 / Animal Study / Preliminary evidenceCBD sped up extinction and prevented reinstatement of methamphetamine-seeking in rats, effects that were partially blocked by inhibiting D2 dopamine receptors in the hippocampus.
2025 / Cross Sectional / Moderate evidenceNational survey found 40.7% of current marijuana users also use CBD, compared to 5.1% of never-marijuana-users, suggesting substantial overlap between these populations.
2025 / Cross Sectional / Preliminary evidencePilot study of 13 CBD retailers in North Carolina found 92% displayed unapproved health claims, most commonly for stress/anxiety, arthritis, and pain.
2025 / Randomized Controlled Trial / Preliminary evidenceRandomized trial of 29 autistic children found CBD oil did not improve social responsiveness but significantly reduced anxiety and parental stress.
2025 / Prospective Cohort / Moderate evidenceLong-term study found CBD reduced seizures by 45-87% through nearly 3 years in 140 patients with treatment-resistant focal epilepsies, regardless of epilepsy type.
2025 / Observational / Moderate evidenceTHC impaired verbal memory as expected, but adding CBD in a 1:1 ratio didn't protect against the effect—challenging a popular harm reduction claim.
2025 / Animal Study / Preliminary evidenceSingle-dose CBD reversed social deficits, repetitive behaviors, and cognitive problems in a mouse autism model, though it did not affect stereotyped movements.
2025 / Cross Sectional / Preliminary evidenceAnalysis of 25,000 relevant tweets found mostly positive public sentiment about CBD for insomnia, though clinical trial evidence remains limited.
2025 / Scoping Review / Moderate evidenceScoping review of 29 studies found CBD shows promise for both anxiety and sleep, but inconsistent methods and dosing across studies limit definitive conclusions.
2025 / Cross Sectional / Moderate evidenceSurvey of 243 caregivers found CBD with clobazam improved seizures (87%), cognition (84%), and communication (76-81%) in patients with severe epilepsy.
2025 / Retrospective Cohort / Moderate evidenceIn 107 patients with severe epilepsy syndromes, 69% achieved at least 50% seizure reduction with CBD—with genetic causes and LGS/TSC showing the best outcomes.
2025 / Narrative Review / Preliminary evidenceCBD fights seizures through multiple mechanisms including neuroinflammation reduction, modulation of several receptor systems, and oxidative stress reduction.
2025 / Randomized Controlled Trial / Preliminary evidenceSmall RCT found CBD 300 mg/day significantly reduced behavioral symptoms of vascular dementia after 4 weeks without cognitive or functional side effects.
2025 / Animal Study / Preliminary evidenceNeonatal rat study found CBD significantly enhanced phenobarbital's antiseizure effects, supporting potential combination therapy for newborn seizures.
2025 / Animal Study / Preliminary evidenceCombined CBD and sodium nitroprusside during early brain development prevented schizophrenia-like symptoms in rats, with stronger effects in females than males.
2025 / Animal Study / Preliminary evidenceCBD improved spatial memory and simultaneously reduced amyloid plaques, tau tangles, neuroinflammation, and oxidative stress in an Alzheimer's mouse model.
2025 / Systematic Review / Moderate evidenceA rigorous review of 8 studies found THC linked to increased psychosis risk while CBD showed potential therapeutic effects—the two cannabinoids may work in opposite directions.
2025 / Meta Analysis / Moderate evidenceMeta-analysis of 21 RCTs found pharmaceutical-grade CBD (SMD -0.61) and THC (SMD -0.65) showed moderate effects for anxiety disorders and PTSD, while CBD-THC mixtures did not reach significance.
2025 / Longitudinal Cohort / Moderate evidenceAmong 1,962 cancer patients, higher CBD doses and swallowed products were associated with the best anxiety improvement—while depression responded mainly to how cannabis was taken.
2025 / Observational / Moderate evidenceAmong 1,962 cancer patients in Minnesota's medical cannabis program, higher CBD doses were linked to better sleep improvement (1.87 points on 0-10 scale), while THC showed no consistent sleep benefit.
2025 / Review / Preliminary evidenceReview found promising preclinical evidence and limited clinical support for CBD in acne, dermatitis, psoriasis, and skin moisturizing, with several clinical trials ongoing.
2025 / Systematic Review / Strong evidenceUmbrella review of 22 systematic reviews found CBD alone is not effective for substance use disorders, but CBD+THC combination (nabiximols) helps cannabis withdrawal and craving.
2025 / Observational / Strong evidenceMulticenter study of 551 children found purified CBD reduced seizures by 50%+ in half of patients with drug-resistant epilepsy, with 14% becoming seizure-free and benefits sustained over 2+ years.
2025 / Observational / Preliminary evidenceCBG reduced nerve pain in rodent models through CB2 receptors and reduced spinal inflammation—a potential non-psychoactive alternative to THC for pain.
2025 / Animal Study / Preliminary evidenceFull-spectrum CBD reversed inflammation-induced depression in rats while CBD isolate did not, providing direct evidence for the "entourage effect" in mood disorders.
2025 / Animal Study / Preliminary evidenceCombining low-dose CBD with resveratrol or alpha-lipoic acid matched high-dose CBD for reducing aggression and depression in PTSD-model mice, though anxiety was unaffected.
2025 / Systematic Review / Preliminary evidenceSystematic review of 11 RCTs finds very limited and low-certainty evidence for cannabis derivatives in autism, with only one trial showing potential benefit for global symptoms.
2025 / Animal Study / Preliminary evidenceMouse study finds oral CBD and THC during pregnancy both impaired fetal growth and caused sex-dependent behavioral changes in offspring, challenging the assumption that CBD is safe for pregnant use.
2025 / Systematic Review / Moderate evidenceSystematic review of 57 studies found that 70% of the highest-quality research reported improvements in anxiety disorders with medicinal cannabis, though reporting standards remain a major issue.
2025 / Cross Sectional / Preliminary evidenceSurvey of 6,600+ people with eating disorders found cannabis and psychedelics rated highest for symptom relief, while most prescription antidepressants were rated ineffective for ED symptoms.
2025 / Animal Study / Preliminary evidenceCBD reversed memory deficits, restored protective brain cells, and reduced neuroinflammation in a mouse model of schizophrenia, working through serotonin and cannabinoid receptor pathways.
2025 / Animal Study / Preliminary evidenceCBD delivered via lipid nanoemulsion reduced anxiety and panic responses in rats at a low chronic dose (2.5 mg/kg), working through serotonin neurons in the brainstem.
2025 / Case Report / Preliminary evidenceCase report shows 87% reduction in pain interference for a mast cell activation syndrome patient treated with CBD oil and orphenadrine over 20 weeks.
2025 / Review / Moderate evidenceReview finds CBD shows promise for acne, psoriasis, eczema, and other skin conditions through the skin's endocannabinoid system, though formulation challenges remain.
2025 / Randomized Controlled Trial / Moderate evidenceCrossover trial found eating a high-fat meal increases CBD absorption by nearly 10-fold, with peak blood levels 17 times higher compared to fasting.
2025 / Animal Study / Preliminary evidenceCBD reduced depressive behaviors and brain inflammation in female rats exposed to both obesity and chronic stress, with effects depending on the type of stressor.
2025 / Randomized Controlled Trial / Strong evidenceRigorous crossover trial found CBD at 50 mg and 300 mg did not improve or impair running performance, mood, or perceived exertion in trained athletes.
2025 / Laboratory / Preliminary evidenceResearchers developed a biodegradable self-emulsifying CBD formulation that achieved slightly higher oral bioavailability (3.8% vs. 3.4%) and peak blood levels than Epidiolex in rat testing.
2025 / Animal / Preliminary evidenceA CBD nanoemulsion protected against Parkinson's-like damage in both the brain and gut of rats, normalizing oxidative stress markers, reducing abnormal protein aggregation, and improving behavior.
2025 / Laboratory / Preliminary evidenceTwo commercial CBD powders containing heavy metals (lead, chromium, zinc) caused oxidative stress, antioxidant enzyme inhibition, and mitochondrial damage in human neuronal cells at concentrations of 10-50 micrograms/mL.
2025 / Systematic Review / Strong evidenceA systematic review of 14 studies (682 children) found that pharmaceutical CBD achieved clinically meaningful seizure reduction in children with severe, treatment-resistant epilepsies, with mostly mild and reversible side effects.
2025 / Observational / Moderate evidenceNationally representative survey of 1,523 U.S. adults found 35% had tried CBD and 7.7% had tried delta-8 THC, with most users citing medical reasons (anxiety, pain, insomnia) except delta-8 users who primarily reported recreational use.
2025 / Laboratory / Preliminary evidenceLab study found CBD blocks Kv2.1 potassium channels in a dose-dependent manner, increasing cell vulnerability to stress-induced damage, a finding with implications for both safety and potential anti-cancer applications.
2025 / Review / Preliminary evidenceA review found THC is associated with impaired sperm quality and altered hormones, while emerging evidence suggests CBD may have protective effects on male reproductive health, though human data remain scarce.
2025 / Clinical Trial / Strong evidenceData from two randomized controlled trials showed that medicinal cannabis (CBD alone or THC/CBD) did not cause liver enzyme elevations in 287 cancer patients over 28 days at doses up to 600 mg CBD per day.
2025 / Laboratory / Preliminary evidenceCannabis extracts from nine genotypes showed antiviral activity against SARS-CoV-2 in lab tests (IC50 below 10 micromolar), but specific phenolic compounds in the plant antagonized the cannabinoids' effects.
2025 / Laboratory / Preliminary evidenceCBD killed several disease-causing oral bacteria at physiological doses but left others completely resistant, potentially explaining higher periodontitis rates in cannabis users through selective microbial dysbiosis.
2025 / Clinical Trial / Strong evidencePhase III randomized trial of 100 patients found a transdermal THC:CBD:CBN cannabis cream significantly reduced diabetic neuropathy pain across all dimensions over 12 weeks, with minimal side effects comparable to placebo.
2025 / Animal / Preliminary evidenceCBD reduced HPV-positive head and neck tumors in mice by enhancing immune cell infiltration through MAPK pathway activation, with no effect in immune-deficient animals, proving the anti-tumor mechanism is immune-dependent.
2025 / Laboratory / Preliminary evidenceTHC and CBD blocked IL-1beta production in human monocytes by inhibiting inflammasome assembly and caspase-1, working at the protein level rather than gene expression, through a mechanism independent of CB2 receptors alone.
2025 / Meta Analysis / Moderate evidenceMeta-analysis of 17 studies (3,359 participants) found cannabinoids modestly but significantly reduced itching (SMD=-0.29) with zero heterogeneity, but showed no significant benefit for skin dryness, redness, quality of life, or atopic dermatitis.
2025 / Laboratory / Preliminary evidenceX-ray crystallography revealed how THC fits inside CYP3A4, the enzyme metabolizing most drugs, with a binding affinity of 1.9 micromolar driven by hydrophobic interactions, providing a structural basis for predicting cannabinoid-drug interactions.
2025 / Systematic Review / Preliminary evidenceSystematic review of 4 clinical (74 participants) and 16 preclinical studies found CBD may reduce opioid cravings and withdrawal anxiety, with a well-tolerated safety profile, though the evidence base remains very small.
2025 / Animal / Preliminary evidenceCBD protected against methamphetamine-induced brain damage in cells and mice by directly binding to and blocking TRPV1 channels, preventing the calcium overload, oxidative stress, and cell death that drive meth-related neurological harm.
2025 / Animal / Preliminary evidenceTen weeks of daily CBD oil at 10 mg/kg caused no structural liver damage in rats, though Kupffer cells (liver immune cells) increased 1.58-fold, suggesting hepatic immune activation without pathology.
2025 / Randomized Controlled Trial / Preliminary evidenceInjectable liposomal CBD provided sustained blood levels and pain relief in arthritic dogs—bypassing the poor oral absorption that limits current CBD products.
2025 / Animal / Preliminary evidenceMouse study found CBD reduced rosacea-like skin inflammation by blocking MAPK signaling pathways, with stronger effects when combined with metronidazole.
2025 / Review / Strong evidenceReview of CBD for drug-resistant childhood epilepsy documents regulatory approval in the US, Europe, and India for Dravet syndrome, Lennox-Gastaut syndrome, and tuberous sclerosis complex, with evidence of seizure reduction and generally favorable safety.
2025 / Review / Moderate evidenceReview of 36 randomized controlled trials found CBD had variable effects on cognition: some anxiety reduction at 300-400 mg, minor Parkinson's benefits at 75-300 mg, but minimal cognitive effects in schizophrenia and substance use disorders.
2025 / Clinical Trial / Moderate evidence4-week study of 499 anxious individuals found all cannabis product types (THC, CBD, 1:1) increased both emotional reactivity to stress and recovery from it compared to non-use, with THC additionally elevating heart rate.
2025 / Clinical Trial / Preliminary evidence6-week pilot trial of 12 anxious patients found a hemp-derived CBD sublingual solution (30 mg/day) reduced anxiety and improved mood, sleep, and cognition with no serious side effects.
2025 / Laboratory / Preliminary evidenceStudy reveals CBD's anticonvulsant mechanism works through enhancing DEC2's suppression of the SCN2A sodium channel, reducing neuronal excitability and seizure susceptibility in laboratory models.
2025 / Clinical Trial / Strong evidencePost hoc analysis of two phase 3 CBD trials found that a 31% reduction in drop seizures, not the traditional 50%, was the threshold for caregiver-perceived meaningful improvement in Lennox-Gastaut syndrome.
2025 / Review / Preliminary evidenceReview finds cannabinoids may complement atopic dermatitis treatment by targeting skin barrier function, inflammation, and itching through the endocannabinoid system, though clinical evidence remains limited.
2025 / Clinical Trial / Moderate evidenceCrossover trial of 20 adults found CBD co-administration increased THC's subjective high, impairment, and blood concentrations, while caffeine had minimal effects on THC outcomes.
2025 / Observational / Strong evidenceGerman multicenter chart review of 202 epilepsy patients found adjunctive CBD achieved 43-44% responder rates at 3 and 12 months, with seizure days dropping from 30 to 18 per month and 67% remaining on treatment at 1 year.
2025 / Observational / Strong evidenceGerman real-world study of 126 patients found CBD plus clobazam achieved 48% seizure response at 3 months for LGS/DS, with 63% tonic-clonic response and 70% treatment retention at 1 year.
2025 / Laboratory / Preliminary evidenceLab study found CBD selectively blocked pro-inflammatory macrophage activation by disrupting metabolic reprogramming and PI3K/Akt signaling, without affecting TNF-alpha production.
2025 / Laboratory Analysis / Moderate evidenceLab analysis found 67% of CBD tinctures sold online had inaccurate labels, with broad-spectrum products significantly less accurate than full-spectrum. Two products contained undisclosed THC.
2025 / Preclinical / Low evidenceLab study found a 1:1 CBD:THC combination most effectively suppressed viral immune receptor (TLR7/8) inflammatory signaling in human immune cells, outperforming either cannabinoid alone.
2025 / Systematic Review / Low evidenceSystematic review of 22 medicinal plants for chemotherapy-induced nausea found cannabis, ginger, and turmeric had the strongest evidence for multi-targeted antiemetic and chemosensitizing effects.
2025 / Preclinical / Moderate evidenceMulti-species study found daily THC causes inflammatory gliosis specifically in the adolescent amygdala through astrocyte CB1 receptors. CBD co-treatment prevented the inflammation but not all neural changes.
2025 / Preclinical / Moderate evidenceMouse study showed CBD and CBG each reduced colitis-related gut pain, and a four-cannabinoid combination achieved the same effect at individually subtherapeutic doses through sodium and calcium channel mechanisms.
2025 / Narrative Review / Low evidenceComprehensive review cataloged CBD interactions across endocannabinoid receptors, ion channels, CYP450 enzymes, inflammatory pathways, and sex hormones, spanning effects on multiple body systems.
2025 / Preclinical / Low evidenceLab study found a cannabinoid product killed papillary thyroid cancer cells by activating the tumor suppressor p53 and suppressing cancer-promoting genes BCL-2 and c-Myc.
2025 / Clinical Trial / Moderate evidenceClinical trial of 12 volunteers found novel sublingual, rectal, and vaporizer cannabis products had faster cannabinoid absorption than approved products like Sativex, with comparable safety.
2025 / Systematic Review / Moderate evidenceDecade-long review of chronic pain drug trials found no breakthroughs, but identified CBD as one of only two drugs tested across fibromyalgia, CRPS, and chronic low back pain, with cannabinoid mechanisms among the most promising targets.
2025 / Preclinical / Moderate evidenceMouse study found low-dose CBD combined with standard IBD drugs olsalazine or cyclosporine enhanced treatment beyond either alone without liver or kidney toxicity.
2025 / Narrative Review / Low evidenceReview found oral CBD has only 6-19% bioavailability due to liver metabolism, while transdermal delivery offers improved absorption by bypassing the digestive system.
2025 / Cross Sectional / Low evidenceSurvey of 1,382 women with chronic pelvic pain and fibromyalgia found 81% of current CBD users reported pain improvement, with correlated improvements in sleep, mood, and fatigue.
2025 / Narrative Review / Low evidenceReview found phytocannabinoids like THCV and CBD may modulate kidney glucose transporters for diabetes management, with pilot data showing THCV lowers fasting glucose without psychoactive effects.
2025 / Preclinical / Moderate evidenceRat study found chronic CBD prevented Alzheimer's-like cognitive decline by activating CB1 receptors and reducing brain inflammation, amyloid-beta, and tau pathology.
2025 / Preclinical / Preliminary evidenceLab experiments found a 3:1 CBD:THC combination killed ovarian cancer cells more effectively than either cannabinoid alone through apoptosis and autophagy.
2025 / Preclinical / Preliminary evidenceA mouse study found targeting both CB2 and TRPV1 receptors reduced osteoarthritis pain and inflammation more effectively than either target alone.
2025 / Observational / Preliminary evidenceAn observational study of 50 autistic children found 60% improved with CBD-rich cannabis oil, with aggression and self-injury showing the most benefit.
2025 / Preclinical / Preliminary evidenceCBC and CBG killed glioblastoma cells in vitro, identifying GPR55 and PINK1 as potential therapeutic targets.
2025 / Review / Moderate evidenceCBD may protect the cardiovascular system through anti-inflammatory and vasoprotective effects, with early trials showing blood pressure reduction.
2025 / Systematic Review / Moderate evidenceCBD and CB2 activation promote bone healing; chronic THC linked to 1.8-3.6x higher spinal fusion failure.
2025 / Longitudinal Cohort / Moderate evidenceIn 11,036 adolescents, cannabis use onset altered cognitive development trajectories—and hair testing showed THC and CBD had different effects on cognition.
2025 / Observational / Preliminary evidenceCBD reduced schizophrenia-like symptoms in animals through two pathways: reducing neuroinflammation and modulating serotonin-MAPK signaling.
2025 / Clinical Trial / Moderate evidenceThree-arm RCT finding that placebo effects account for significant improvements attributed to low-dose CBD oil for psychological distress in university students.
2025 / Preclinical / Preliminary evidenceLab study showing CBD can protect human cartilage cells from ferroptosis (iron-dependent cell death), suggesting a potential mechanism for joint protection relevant to osteoarthritis.
2025 / Preclinical / Preliminary evidencePreclinical study showing cannabis extract reduces inflammation in a rat dermatitis model, supporting potential applications for inflammatory skin conditions.
2025 / Clinical Trial / Strong evidenceClinical trial in 60 adults showing that legal hemp CBD products containing trace THC can trigger positive drug tests, with effects depending on THC dose level.
2025 / Retrospective Cohort / Preliminary evidenceAmong 71 older cannabis users, 86% had genetic variants altering cannabinoid metabolism—explaining why the same dose affects people so differently.
2025 / Systematic Review / Moderate evidenceSystematic review and meta-analysis showing CBD consistently reduces neuroinflammation in preclinical Alzheimer's models with promising but limited clinical signals.
2025 / Preclinical / Preliminary evidencePreclinical study showing CBD inhibits osteosarcoma growth by directly binding NF-kB and disrupting an inflammatory signaling loop, validated in cell and mouse models.
2025 / Preclinical / Preliminary evidencePreclinical study showing THC and CBD both suppress B-cell immune activation but through distinct metabolic pathways that differ between young and aged mice.
2025 / Preclinical / Preliminary evidenceLab study showing CBD kills extensively drug-resistant A. baumannii and synergizes with antibiotics, reducing needed antibiotic concentrations by up to 1,000-fold through membrane disruption.
2025 / Preclinical / Preliminary evidenceLab study showing CBD and green tea EGCG complement each other to block SARS-CoV-2 at multiple stages — CBD reduces virus entry receptor while EGCG suppresses spike protein.
2025 / Preclinical / Preliminary evidencePreclinical study showing CBD inhibits colorectal cancer by targeting the HIF-1alpha/LDHA glycolysis pathway, disrupting the metabolic reprogramming that fuels tumor growth.
2025 / Preclinical / Preliminary evidencePreclinical study showing a 100:1 CBD:THC ratio pretreatment rescues CGRP-induced migraine symptoms including light aversion and pain in mice.
2026 / Randomized Controlled Trial / Moderate evidenceA rigorous crossover trial found that even 20 mg of CBD altered the body's natural cannabinoid levels—with men and women showing different dose-response patterns.
2026 / Narrative Review / Preliminary evidenceMayo Clinic review of CBD's potential in cardiovascular medicine, covering anti-inflammatory and cardioprotective mechanisms across pericarditis, ischemic heart disease, and heart failure.
2026 / Preclinical / Preliminary evidenceRat study finds adolescent THC vapor exposure doesn't increase alcohol consumption but alters the psychological framework of drinking behavior differently in males and females.
2026 / Preclinical / Preliminary evidenceRat study shows CBD and aerobic exercise synergistically protect insulin-producing beta cells in obesity through the PI3K/AKT/PDX1 pathway, with CBD driving functional improvement.
2026 / Preclinical / Preliminary evidenceRat study demonstrates CBD protects the heart from ischemia-reperfusion injury by boosting mitochondrial biogenesis and suppressing inflammation through the SIRT-1/PGC-1α pathway.
2026 / Review / Moderate evidenceReview of how cannabis's 100+ compounds interact with molecular targets in the body, highlighting major gaps in understanding beyond THC and CBD, especially for acid cannabinoids.
2026 / Systematic Review / Moderate evidenceMeta-analysis of 9 trials with 2,544 MS patients confirms cannabis-based therapies improve spasticity, especially with longer treatment duration, with mild side effects like dizziness and dry mouth.
2026 / Preclinical / Preliminary evidenceSynthetic CBD analogues are over 13 times less toxic than natural CBD to brain cells while maintaining protective effects against alcohol-induced damage, supporting their development for alcohol use disorder.
2026 / Systematic Review / Moderate evidenceThe Cochrane Review found cannabis provides modest neuropathic pain relief for a minority of patients, but side effects are common—the benefit-harm balance is delicate.
2026 / Cross Sectional / Moderate evidenceNational survey finds 90 million US adults have tried CBD, with one-third of users taking it to replace or supplement conventional medications — most commonly OTC pain relievers like ibuprofen.
2026 / Preclinical / Preliminary evidenceRat study shows CBD helps extinguish meth-seeking behavior and prevents relapse through D2 dopamine receptors in the hippocampus, identifying a specific brain mechanism for CBD's anti-addiction potential.
2026 / Laboratory Analysis / Moderate evidencePrecise vapor pressure measurements show THC, CBD, and CBN likely exist primarily as vapor (not aerosol) in exhaled breath, explaining why current cannabis breathalyzers give inconsistent results.
2026 / Preclinical / Preliminary evidenceLab study shows CBD and CBG alter melanoma cell membranes, boost endocannabinoid levels, and reduce inflammatory signals — effects enhanced when combined with UVA radiation.
2026 / Clinical Trial / Moderate evidenceTwo randomized trials found CBD up to 1200mg/day was tolerable but no better than placebo for alcohol use disorder or co-occurring PTSD, despite both groups showing large improvements.
2026 / Observational / Preliminary evidenceCBD reduced opioid self-administration in rats with nerve pain without reducing oxycodone's analgesic effects—a potential path to safer opioid prescribing.
2026 / Randomized Controlled Trial / Moderate evidenceIn a rigorous trial, pharmaceutical CBD altered brain waves and improved cognitive abilities in boys with severe autism—with blood CBD levels predicting the brain changes.
2026 / Preclinical / Moderate evidenceWell-designed rat study finds CBD does not protect against postmenopausal bone loss and may even increase bone resorption, ruling it out as a standalone osteoporosis treatment.
2026 / Narrative Review / Preliminary evidenceReview describes how CBD's interactions with multiple ion channels — separate from cannabinoid receptors — offer a novel approach to liver cancer prevention and treatment.
2026 / Systematic Review / Moderate evidenceUpdated systematic review of 25 RCTs found THC products slightly reduce chronic pain but with significant side effects; CBD-dominant products showed no benefit.
2026 / Preclinical / Preliminary evidenceLab study found CBD activated anti-aging pathways SIRT1 and autophagy in stem cells, preserving their function and delaying cellular aging — a potentially significant finding for regenerative medicine.
2026 / Cross Sectional / Moderate evidenceNational survey of nearly 70,000 U.S. teens found THC vaping linked to depression while CBD-only vaping was associated with higher anxiety symptoms — a surprising finding that challenges simple narratives.
2026 / Systematic Review / Moderate evidenceSystematic review of 57 studies and 971 patients found prescription CBD (Epidiolex) reduced seizures across 37 different rare epilepsy types beyond its three approved conditions, with some patients achieving seizure freedom.
2026 / Clinical Trial / Preliminary evidenceProof-of-concept study in 7 opioid use disorder patients found CBD improved heat pain tolerance in those on buprenorphine but not methadone, with excellent safety at doses up to 1200mg — suggesting medication type matters for CBD pain relief.
2026 / Cross Sectional / Strong evidence2023 national survey reveals 15% of Americans use cannabis monthly, with distinct age patterns: young adults favor dual cannabis-CBD use, middle-aged adults prefer cannabis-only, and seniors lean toward CBD-only.
2026 / Clinical Observation / Preliminary evidenceFirst study using teacher assessments found CBD-rich cannabis oil significantly improved hyperactivity, anxiety, and emotional regulation in 53 children with autism over 3-6 months — promising but uncontrolled.
2026 / Narrative Review / Moderate evidenceReview of preclinical evidence shows CBD protects brain support cells (glia) after stroke by reducing inflammation, oxidative stress, and barrier damage — a promising multi-target neuroprotective approach.
2026 / Preclinical / Moderate evidenceComprehensive preclinical study showed CBD reduced alcohol dependence across every dimension tested — consumption, withdrawal, anxiety, relapse, and brain damage — while leaving non-alcohol rewards unaffected.
2026 / Narrative Review / Preliminary evidenceComputational study modeled CBD's interactions with five brain receptor types involved in seizures, finding multi-target binding that may explain its broad anti-epileptic activity.
2026 / Systematic Review / Moderate evidenceScoping review found CBD failed to beat placebo for cocaine addiction in clinical trials despite promising animal data — well-tolerated but not effective as standalone treatment, highlighting the preclinical-to-clinical translation gap.
2026 / Systematic Review / Moderate evidenceSystematic review confirms CBD potently inhibits liver enzymes (CYP3A4, CYP2C9, CYP2C19) that process 80% of medications — a critical safety concern for the millions combining CBD with prescriptions.
2026 / Systematic Review / Moderate evidenceSystematic review shows CBD has multi-target anti-cancer activity — inhibiting growth, triggering cell death, blocking spread, and modulating immunity — but almost all evidence is preclinical and clinical trials are urgently needed.
2026 / Narrative Review / Moderate evidenceReview finds THC disrupts male fertility through multiple pathways — reducing testosterone, impairing sperm motility and shape, and disrupting hormonal signaling via cannabinoid receptors in the testes.
2026 / Clinical Trial / Moderate evidenceClinical study of 33 subjects found genetics significantly affect CBD processing and side effects — certain gene combinations caused 5.6x more diarrhea, pointing toward personalized CBD dosing based on pharmacogenomics.
2026 / Preclinical / Preliminary evidencePreclinical study discovers CBD improves cognition after traumatic brain injury through a novel mechanism — directly binding the SET protein to activate a neuroprotective pathway previously unknown in cannabinoid research.
2026 / Clinical Trial / Moderate evidenceA 10-week trial found that daily broad-spectrum CBD use produced WADA-prohibited cannabinoids (CBG, CBDV) in urine, with exercise significantly increasing concentrations — posing real anti-doping risks for athletes.
2026 / Clinical Trial / Preliminary evidenceA small pilot trial found that CBD and THC capsules reduced specific endocannabinoid mediators in people with HIV but did not change gut bacteria composition over 12 weeks.
2026 / Retrospective Analysis / Moderate evidenceA study of 53 children found that CBD (Epidyolex) reduced drug-resistant epileptic spasms by ≥50% in nearly 60% of patients, with the best results in children with Down syndrome and cortical malformations.
2026 / Cross Sectional / Moderate evidenceA study of 1,492 young Spanish adults found that most would try cannabis if legalized, with existing CBD+THC product users showing the highest demand for both medicinal and recreational cannabis.
2026 / Clinical Trial / Strong evidenceA rigorous crossover trial found CBD had no effect on brain excitability or sedation at either low or high doses, suggesting its anti-epileptic benefits may come from drug interactions rather than direct activity.
2026 / Clinical Trial / Preliminary evidenceA randomized trial found 300 mg CBD improved sleep more than 50 mg CBD in high-worry individuals, but the difference from placebo was not statistically significant after 2 weeks of daily use.
2026 / Randomized Controlled Trial / Preliminary evidencePharmacokinetic trial of nanodispersible CBD solution found food tripled blood absorption levels compared to fasting, with significant implications for dosing consistency.
2026 / Laboratory Analysis / Moderate evidenceAnalysis of 13 CBD oils found hazardous contaminants including hormone disruptors (phthalates) and a carcinogenic mycotoxin (zearalenone), along with antimicrobial, neurotoxic, and genotoxic compounds.
2026 / Preclinical / Preliminary evidenceEx vivo placental study shows CBD crosses to the fetal side and dilates placental blood vessels by 36%, while THC constricts them — revealing opposing cannabinoid effects during pregnancy.
2026 / Review / Moderate evidenceA comprehensive review finds cannabis disrupts the placental endocannabinoid system, linking use to fetal growth restriction and preeclampsia, with emerging evidence of transgenerational effects through epigenetic changes.
2026 / Review / Moderate evidenceA comprehensive review finds mixed evidence for cannabis as a pain treatment, with effectiveness depending on the cannabinoid, delivery method, and type of pain — underscoring the need for more rigorous research.
2026 / Preclinical / Preliminary evidenceLab study finds CBD is much more effective than CBDA against colorectal cancer cells, with a whole-plant cannabis extract outperforming purified compounds — supporting entourage effects in anti-cancer activity.
2026 / Observational / Preliminary evidenceWomen with endometriosis using prescribed medicinal cannabis reported pain reduction from 5.5 to 3.8 and quality-of-life scores nearly halving over 12 weeks, though the study lacked a control group.
2026 / Meta Analysis / Moderate evidenceJAMA review found strong evidence for cannabinoids treating nausea, appetite loss, and seizures, but guidelines recommend against inhaled or high-potency cannabis for most conditions.
2026 / Observational / Preliminary evidenceWell-powered rat study found oral CBD did not significantly reduce acute opioid withdrawal symptoms, with limited sex-specific effects in the protracted phase.
2026 / Preclinical / Preliminary evidencePreclinical study shows CBD protects neuron-like cells from ferroptosis (iron-dependent cell death) during oxygen deprivation by modulating antioxidant defenses, Nrf2 signaling, and iron metabolism.
2026 / Preclinical / Preliminary evidenceRat study shows CBD supplementation reduces early inflammatory lipid markers in diet-induced fatty liver disease by shifting the balance from pro-inflammatory to anti-inflammatory pathways.
2026 / Systematic Review / Moderate evidenceSystematic review of 57 studies finds CBD shows dental promise for pain, oral inflammation, and radiation-induced mucositis, with emerging but limited evidence for regenerative applications.
2026 / Laboratory Analysis / Preliminary evidenceLab study finds CBD inhibits all 20 tested clinical strains of drug-resistant Enterococcus bacteria at very low concentrations (MIC ≤ 1 μg/mL), with pure CBD outperforming CBD oils.
2026 / Preclinical / Preliminary evidenceLab study reveals THC, CBD, and CBN all activate the human PXR receptor (which controls drug metabolism) at much lower concentrations than rodent versions, suggesting underestimated drug interaction risks.
2026 / Preclinical / Preliminary evidenceCell study shows THC promotes fat uptake and inflammation in macrophages via CB1/NFκB pathway while CBD partially counteracts these effects, with implications for atherosclerosis risk in cannabis users.
2026 / Preclinical / Preliminary evidencePreclinical study shows CBD reverses methamphetamine-induced brain damage by suppressing sigma 1 receptor expression, validated through three independent experimental approaches in cells and mice.
2026 / Preclinical / Preliminary evidenceLow-dose CBD reduced cocaine self-administration in female mice by altering reward pathways, while higher doses showed paradoxical effects. Males showed no response, highlighting critical sex differences.
2026 / Narrative Review / Preliminary evidenceReview mapped CBD's gut-protective mechanisms: antioxidant pathway activation, anti-inflammatory signaling, barrier integrity preservation, and microbiota modulation.
2026 / Preclinical / Preliminary evidenceChronic CBD reduced nerve pain in all rat anxiety lineages but had differential anxiety effects, with anxiety-prone animals responding less — suggesting individual anxiety traits may affect CBD treatment outcomes.
2026 / Preclinical / Preliminary evidenceGenetically modified fruit fly with chronic pain-related sodium channel mutation responds to CBD but not conventional treatment, validating a fast, ethical model for screening new pain medications.
2026 / Retrospective Analysis / Moderate evidenceLGS diagnoses in the US jumped ~60% after the 2018 FDA approval of CBD for the condition, then returned to baseline, suggesting treatment availability may have influenced diagnostic practices.
2026 / Randomized Controlled Trial / Moderate evidencePhase 2 RCT: CBD missed primary cardiac endpoints but significantly reduced LV mass and showed anti-inflammatory trends in myocarditis.
2026 / Narrative Review / Strong evidenceReview confirms THC impairs driving for 4-5 hours, CBD does not impair driving, and alcohol plus cannabis amplifies the effect.
2026 / Animal Study / Preliminary evidenceNon-psychoactive hemp seed extract slowed colorectal cancer cell growth by triggering metabolic stress; adding an autophagy inhibitor boosted the effect by 30%.
2026 / Animal Study / Preliminary evidenceHigh-dose CBG impaired sustained attention in female rats but not males, contradicting marketing claims of cognitive enhancement.
2026 / Review / Preliminary evidenceReview finds cannabinoids modulate autophagy in oral tissues via mTOR/AMPK pathways, with potential for oral cancer and periodontal disease.
2026 / Animal Study / Preliminary evidenceDaily CBD in Alzheimer mice reduced brain immune cell reactivity but did not improve cognition, behavior, or brain volume.
2026 / Review / Moderate evidenceReview maps CBD's extensive receptor interactions beyond the endocannabinoid system, highlighting both therapeutic potential and complexity for Parkinson's disease.
2026 / Meta Analysis / Strong evidenceMajor meta-analysis shows cannabis co-use reduces tobacco quit odds by 35%, but CBD interventions cut cigarette consumption by 40%, suggesting a promising new cessation approach.
2026 / Animal Study / Moderate evidenceCBD prevented precancerous colorectal growths in two mouse models by targeting EEF1B2 to suppress immune-blocking cells, enabling stronger anti-tumor immune responses.
2026 / Review / Moderate evidenceReview finds preclinical evidence supporting cannabinoid antitumor activity against skin cancers through multiple mechanisms, with topical CBD formulations as a promising delivery approach.
2026 / Narrative Review / Preliminary evidenceReview explored how age-related endocannabinoid system changes and chronic inflammation ('inflammaging') create a rationale for cannabinoid pain therapy in older adults, though clinical evidence is limited.
2026 / Narrative Review / Moderate evidenceReview found hemp-derived compounds from seeds, leaves, and flowers show neuroprotective potential across epilepsy, Alzheimer's, Parkinson's, and MS — mostly in preclinical studies.
2026 / Animal Study / Preliminary evidenceStudy finds lesser-known cannabinoids CBV and THCV reduce pain through both vanilloid and cannabinoid receptor pathways in a genetic model organism.
2026 / Randomized Controlled Trial / Moderate evidenceRCT finds oral CBD at 60 mg/day did not improve psoriasis severity versus placebo, though temporary benefits in itch and sleep onset were observed.
2026 / Animal Study / Moderate evidenceCBD:THC (99:1) mixture enhanced microglial clearance of Alzheimer's plaques in mice but also worsened anxiety and depression behaviors, highlighting the therapeutic trade-off.
2026 / Animal Study / Preliminary evidenceA cell study found CBG was genotoxic at moderate concentrations, highly toxic at high concentrations, and failed to reduce neuroinflammation in microglial cells, challenging claims of CBG as a safe anti-inflammatory cannabinoid.
2026 / Prospective Cohort / Moderate evidenceA crossover study of 20 TMD patients found 90 days of sublingual THC/CBD (1:1 ratio, 10 mg/day) halved pain scores, improved jaw function, and nearly eliminated pain sensitization, with large effect sizes and minimal placebo response.
2026 / Randomized Controlled Trial / Strong evidenceThe first RCT of cannabis for acute migraine found vaporized THC+CBD significantly superior to placebo for pain relief (67% vs 47%), pain freedom, and symptom freedom at 2 hours, with sustained benefits to 48 hours, while CBD alone was ineffective.
2026 / Scoping Review / Preliminary evidenceScoping review of 24 studies finds CBD shows bone-protective effects in about half of preclinical models, enhancing bone-building cells and suppressing bone-breakdown cells through multiple molecular pathways.
2026 / Retrospective Cohort / Moderate evidenceRetrospective study of 29 pediatric patients with intractable epilepsy found CBD therapy had 86%+ retention at 2 years, with nearly 80% achieving at least 50% seizure reduction across diverse genetic and non-genetic causes.
2026 / Animal Study / Preliminary evidencePreclinical study found a chemically characterized CBD-rich cannabis extract reduced inflammatory markers in cells and showed dose-dependent anti-inflammatory and analgesic effects in animal models.
2026 / Narrative Review / Preliminary evidenceNarrative review finds acidic cannabinoids (THCA, CBDA, CBGA, CBCA) have distinct therapeutic properties including neuroprotective and anti-inflammatory effects, but chemical instability and absent human trials limit clinical use.
2026 / Observational / Preliminary evidenceLab study found CBD killed kidney cancer cells but equally killed normal kidney cells, lost effectiveness in the presence of serum proteins, and required concentrations far beyond clinically achievable levels.
2026 / Observational / Preliminary evidenceSystematic comparison of ten non-psychoactive cannabinoids found CBDV was the most anti-inflammatory, and combinations with CBG or CBN plus cannabis plant matrices showed synergistic effects.
2026 / Pilot Study / Preliminary evidencePilot trial of rectal CBD/hyaluronic acid suppositories found 81% of men with chronic pelvic pain improved over 30 days, with significant reductions in symptom scores.
2026 / Randomized Controlled Trial / Preliminary evidenceRCT found THC/CBD reduced total sleep time by 25 minutes and dramatically cut REM sleep by 34 minutes in insomnia patients — challenging the cannabis-aids-sleep belief.
2026 / Observational / Preliminary evidenceCell-based screening detected synthetic cannabinoid activity in 6 of 23 vape liquids faster and cheaper than chemical analysis, and flagged unexpected CB1-interfering substances in five others.
2026 / Animal Study / Preliminary evidenceRat study found neonatal CBD treatment reduced some immediate pain responses but failed to prevent long-term anxiety from early pain exposure, while raising safety concerns including elevated stress hormones.
2026 / Scoping Review / Preliminary evidenceScoping review of 14 studies found THC/CBD combinations showed modest opioid-sparing potential after orthopedic surgery, while CBD-only interventions had inconsistent results.
2026 / Animal Study / Preliminary evidenceFourteen days of daily CBD reduced T cell and B cell populations in rat spleens while leaving natural killer cells and their cancer/infection-fighting ability intact.
2026 / Animal Study / Preliminary evidenceRat study found a hemp extract with only 2.5 mg/kg CBD was more effective than 80 mg/kg of pure CBD at reducing meth relapse-like behavior, supporting the therapeutic value of full-spectrum cannabinoid preparations.
2026 / Observational / Moderate evidenceUK registry data from 497 fibromyalgia patients showed medical cannabis was linked to improved pain, anxiety, sleep, and quality of life, though nearly half reported side effects.
2026 / Animal Study / Preliminary evidenceFirst preclinical evidence that 14 days of inhaled CBD pretreatment significantly reduced glioblastoma tumor growth in mice by modulating immune checkpoint markers.
2026 / Animal Study / Preliminary evidenceCBD reduced CD47 (an immune evasion signal) on leukemia cells and triggered apoptosis through VDAC-1 oligomerization, a specific mitochondrial mechanism.
2026 / Meta Analysis / Strong evidenceFirst meta-analysis of CBD prevalence found nearly 29% lifetime use in North America vs. 13% in Europe, with opposite patterns for clinical vs. community use between continents.
2026 / Animal Study / Preliminary evidenceCannflavin B, a non-psychoactive cannabis flavonoid, normalized social behavior, reduced anxiety in females, and corrected brain wave abnormalities in an adolescent rat model of autism.
2026 / Animal Study / Preliminary evidenceCBD protected mice from acute liver injury by preventing degradation of the mitochondrial protein MFN2, reducing inflammation, cell death, and oxidative stress.
2026 / Animal Study / Preliminary evidenceCBD inhibited melanoma growth and metastasis in mice by activating PPARgamma-TET1 to demethylate LRSAM1, a newly identified anti-cancer gene.
2026 / Animal Study / Preliminary evidenceCBD reversed depression-like behavior in mice by restoring mitochondrial function, reducing oxidative stress, and decreasing neuroinflammation in the hippocampus.
2026 / Animal Study / Preliminary evidenceCombining CBD with the non-psychoactive cannabinoid CBG cut the anti-seizure CBD dose by over 50% in mice — the first detailed dose-response data for this combination.
2026 / Review / Moderate evidenceReview found cannabinoid receptor agonists reduced chemotherapy-induced organ damage in preclinical studies by suppressing inflammation and oxidative stress.
2026 / Randomized Controlled Trial / Preliminary evidenceRandomized trial found topical THC and CBD balms well tolerated for breast cancer treatment-related joint pain, with 86% reporting improvement and THC balm outperforming CBD.
2018 / Randomized Controlled Trial (Phase 3, Double Blind, Placebo Controlled) / Strong — Gold Standard RCT Design Published In The Lancet evidencePhase 3 RCT in The Lancet: CBD reduced Lennox-Gastaut drop seizures by 43.9% vs 21.8% placebo (p=0.0135). The second RCT that led to Epidiolex becoming the first FDA-approved cannabis drug.
1980 / Double Blind, Placebo Controlled Clinical Trial (Two Phases: Safety + Efficacy) / Moderate — Gold Standard Design But Very Small Sample Size (N=15 For Efficacy) evidenceThe first CBD epilepsy trial (1980): 10% of CBD patients still seizing vs 90% placebo. Published by Carlini and Mechoulam, ignored for 40 years, vindicated by Epidiolex trials in 2017-2018.
2018 / Randomized Controlled Trial (Dose Ranging, Double Blind, Class I Evidence) / Strong For Safety Characterization; Underpowered For Efficacy (N=34) evidenceSmall dose-ranging trial (34 Dravet patients, ages 4-10) that identified the CBD-clobazam interaction explaining somnolence, confirmed the CBD-valproate liver signal, and showed dose-proportional pharmacokinetics.
2012 / Randomized Controlled Trial / Strong evidenceCBD matched amisulpride for treating acute schizophrenia with dramatically fewer side effects — working through a novel mechanism: enhancing the brain's own anandamide signaling rather than blocking dopamine.
2011 / Preclinical / Moderate evidenceHarvard-affiliated preclinical study showing CBD selectively kills both triple-negative and ER-positive breast cancer cells through coordinated autophagy and apoptosis while sparing normal mammary cells.
2008 / In Vitro / Preliminary evidenceAll five major cannabinoids killed MRSA as effectively as vancomycin — opening an unexpected new front in the fight against antibiotic-resistant superbugs.
2018 / Randomized Controlled Trial / Moderate evidenceThe first controlled trial of CBD for dog arthritis — from Cornell University — found significant pain reduction and activity improvement. Dogs can't placebo, making this unusually clean evidence.
2018 / Randomized Controlled Trial / Strong evidenceLargest CBD-for-psychosis RCT: 88 patients, 6 weeks. CBD 1000mg/day significantly reduced positive symptoms with zero side effect burden.
2024 / Crossover / Preliminary evidenceCannabis made running more enjoyable (90.5%), less painful (69%), and more motivating (57%) — without improving performance. CBD worked better than THC for exercise enjoyment.
2017 / Randomized Controlled Trial / Strong evidenceNEJM RCT: CBD reduced seizures 39% vs 13% placebo in Dravet syndrome. Led to Epidiolex FDA approval — first cannabis-derived drug.