Browse more cannabis research, findings, methods, and limitations.
Systematic review of 64 studies found synthetic cannabinoids (K2/Spice) caused more severe toxicity than THC, with 14 studies reporting deaths and seizures as common symptoms.
Multi-site study of 1,185 people found cannabis and childhood trauma interacted to predict earlier psychosis onset, with hippocampal volume as a biological mediator.
Meta-analysis of 23 studies found a modest link between prenatal cannabis and birth defects overall, but most associations disappeared after adjustment except for two rare defects.
A dual enzyme inhibitor called AKU-005 boosted endocannabinoid levels in meningeal tissue from rats and humans, reducing pain-related nerve firing through CB1 receptors.
High stress sensitivity in heroin treatment patients predicted worse psychopathology, impaired well-being, and greater social dysfunction, especially among women with low income.
Expert commentary outlines the clinical tradeoffs of prescribing stimulants for ADHD in youth who also use cannabis, noting that untreated ADHD may itself increase substance use risk.
New pyrazole-based synthetic cannabinoids designed to bypass China's 2021 ban showed minimal receptor activation and even antagonistic properties in lab tests.
Among 709 youth at risk for psychosis, persistent negative symptoms were predicted by poor late-adolescent social functioning — while those without persistent symptoms actually used more cannabis.
In 660 virally suppressed HIV patients, tobacco, alcohol, and cannabis use showed no significant association with immune inflammation markers, though chemsex drugs trended toward worse immune ratios.
A systematic review of 20 studies found complex relationships between cannabis and ADHD, with self-medication common but limited evidence of benefit and clear risks.
A driving simulator study found no linear THC dose-response for impairment, but legal thresholds in blood and saliva did detect increased lane weaving.
Researchers used Google Trends and public databases to show that rising cannabis interest in the UK has paralleled increases in psychosis cases, though the method cannot prove causation.
A phase 1b trial in 8 Parkinson's patients found three THC/CBD oil formulations tolerated at similar doses with no serious adverse events.
THC triggered an anxiety-linked dopamine receptor mechanism in adult but not adolescent brains, potentially explaining why teens feel less negative effects from cannabis — and keep using it.
A review of all canine CBD research found some evidence for osteoarthritis pain relief, but highlighted small studies, variable methods, and no long-term safety data.
Higher nitrogen fertilization increased cannabis leaf mass but decreased cannabinoid concentration and per-plant yield, with optimal nitrogen between 60-210 mg/L.
In a mouse seizure model, combining CBD with a low dose of THC (15:1 ratio) modestly improved seizure protection compared to CBD alone.
A longitudinal study found prenatal alcohol exposure independently predicted heavier drinking and greater alcohol tolerance at age 19, separate from ADHD and environmental factors.
Marijuana use during pregnancy reduced birth weight even with first trimester only exposure, while continued use additionally decreased head circumference.
A randomized trial found that a CBD/THC drug caused small cognitive declines in verbal fluency and twice as many cognitive side effects compared to placebo in Parkinson's patients.
A review of 3,515 donor offers found that lungs from donors with marijuana, opioid, or cigarette use history provided equivalent transplant outcomes, despite lower acceptance rates.
Massachusetts policymakers highlight that cannabis science hasn't kept pace with legalization, particularly around impaired driving detection and medical cannabis standardization.
Quebec's government cannabis stores reach at-risk users at similar rates to illegal sources, with the key advantage that legal purchasers are 4x more likely to know their product's cannabinoid content.
A cumulative meta-analysis of 27 studies found prenatal cannabis exposure increases preterm birth risk by 35%, with the finding now statistically stable.
THC-rich cannabis extract delivered higher THC levels to the brain than pure THC in mice, but only CBD reduced neuropathic pain.
US medical marijuana use rose from 1.6% to 2.4% (2015-2019) as painkiller use declined, but prescription painkiller users were ~2x more likely to also use medical marijuana.
Veterans with alcohol use disorder carrying a BDNF gene variant showed faster age-related brain decline in the prefrontal cortex, along with higher rates of cannabis use disorder and depression.
A comprehensive toxicology assessment found a CBD-rich hemp extract non-mutagenic and well-tolerated in rats for 90 days, with a NOAEL of ~186 mg/kg/day.
A review found preliminary evidence that medical cannabis may help some autism symptoms and CBD gel may help Fragile X, but rigorous controlled trials in children are almost entirely absent.
Vaping legal CBD-rich cannabis (<1% THC) caused no driving impairment but left detectable THC in blood for up to 5 hours, creating potential legal issues for drivers.
In two European cohorts, cannabis use at age 16 predicted psychotic-like experiences independent of genetic risk for schizophrenia, with no gene-environment interaction.
In a 24-week opioid treatment trial, cannabis use showed no significant effect on opioid use, craving, or withdrawal, with Bayesian analysis actively supporting the null hypothesis.
A randomized trial found that adding CBD at ratios up to 3:1 did not reduce THC-induced memory impairment or psychotic symptoms in 46 infrequent cannabis users.
A UK medical cannabis registry of 312 patients showed significant improvements in anxiety, sleep, and quality of life over 6 months with a low adverse event rate.
In 35 children with treatment-resistant epilepsy, CBD/THC combination achieved 94% seizure reduction response rate vs 32% for CBD isolate and 18% for broad-spectrum CBD.
CBD achieved a 69% responder rate and 12% seizure freedom in 78 patients with drug-resistant epilepsy beyond the conditions it's currently approved for.
A new eco-friendly extraction method detects 31 synthetic cannabinoids in just 300 µL of blood plasma using switchable solvents instead of toxic chemicals.
Cannabis use in HIV patients on treatment was linked to reduced immune activation and T-cell aging markers without affecting anti-HIV immunity or the viral reservoir.
In over 10,700 children from the ABCD study, early prenatal cannabis exposure was linked to weaker connectivity between brain networks for attention and emotional processing.
The kratom alkaloid mitragynine required cannabinoid receptors to relieve neuropathic pain in mice and restored chemotherapy-disrupted endocannabinoid levels in the spinal cord.
A review found the endocannabinoid system and gut microbiota both influence endometriosis through inflammation and immune pathways, with potential for integrated therapeutic approaches.
A systematic review of 61 studies found recreational cannabis legalization produced mixed effects: some increased young adult use and healthcare visits, but minimal adolescent impact.
Five-year Italian DUI study found 55% of cannabis-positive drivers only had inactive metabolites in blood — delayed testing couldn't confirm recent use or impairment at time of driving.
Among California cannabis users, only 44% of 26-33 year olds were vaccinated for COVID-19 vs 72% of 18-21 year olds, with race, insurance, and cannabis use orientation predicting hesitancy.
Among 802 first-episode psychosis patients, premorbid deterioration was linked to daily high-potency cannabis use rather than higher genetic risk for schizophrenia.
A review reveals how adenosine A2A and cannabinoid CB1 receptors form physical complexes in brain circuits, creating drug targets for Parkinson's disease and restless legs syndrome.
Hemp seeds provide good protein quality and a favorable fatty acid ratio for dogs and cats, but tryptophan deficiency means they need complementary protein sources.
The common additive pFPP found with synthetic cannabis AMB-FUBINACA in New Zealand did not increase toxicity and actually modestly blunted some physiological effects.
International experts identified modifiable cannabis risk factors for psychosis and developed harm reduction recommendations, noting uncertain CBD protective effects.
A German study protocol describes a representative web-based survey of 256 medical cannabis patients using validated questionnaires to assess therapy outcomes across multiple conditions.