Browse more cannabis research, findings, methods, and limitations.
Cannabis users under the influence showed impaired emotion recognition (especially for positive stimuli) but maintained emotional empathy, with specifically dampened reactions to negative stimuli.
A 21-year-old with prior cannabis psychosis developed catatonia after resuming use, triggering rhabdomyolysis, kidney injury, and autonomic instability.
Review reveals the spinal endocannabinoid system has dual effects on neuropathic pain: typically relieving it, but paradoxically promoting pain under certain pathological conditions.
Analysis of US states found marijuana legalization is significantly predicted by socioeconomic factors including use prevalence and household income, suggesting legalization requires a supportive broader context.
Mouse study found prenatal cannabis exposure impaired metabolic control in female but not male offspring, with paradoxically different effects depending on diet.
Mouse study found oral bacteria enriched in cannabis smokers can cause anxiety through metabolites that impair mitochondrial function and GABA signaling in the brain, without bacteria reaching the brain.
Mini-review summarizes preclinical evidence that cannabinoids can inhibit tumor growth, trigger cancer cell death, and suppress blood vessel formation, though clinical translation faces major challenges.
Analysis of national survey data found that medical cannabis laws were associated with shifts from frequent to occasional non-medical opioid use, with the effect concentrated among people with cannabis use disorder.
Two nationally representative Mexican surveys found recreational cannabis use was more common in wealthier, more educated municipalities, and this socioeconomic gradient grew steeper between 2016 and 2023.
A study of 1,037 adults in Greenlandic substance use treatment found that among women, parental cannabis abuse and physical abuse were linked to high cannabis use, while no specific ACE-substance associations emerged for men.
Researchers 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.
A review of the two-hit hypothesis of schizophrenia found that animal studies do not consistently show adolescent cannabis worsening outcomes after prenatal immune activation, complicating the expected risk narrative.
A six-month observational study of 60 fibromyalgia patients found Bedrocan medical cannabis significantly improved both overall fibromyalgia severity and multiple gastrointestinal symptoms, though the study lacked a control group.
A 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.
Two 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.
A 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.
Omega-3 supplementation reversed cognitive and emotional deficits from prenatal THC exposure in male rat offspring but not females, while brain lipid metabolism disruptions persisted in both sexes.
Among 7,332 adolescents in the ABCD study, witnessing violence was consistently linked to stronger positive expectations about cannabis, regardless of race/ethnicity, with advantaged neighborhoods providing only modest buffering.
Nationally 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.
Nationally representative survey found delta-8 THC use was highest in states prohibiting marijuana (10.9%) and lowest where delta-8 was directly regulated (3.9%), suggesting both marijuana access and targeted regulation reduce delta-8 consumption.
Saliva testing of 1,024 NYC nightclub attendees detected THCA-A in 11.7% and CBN in 8.9%, with significant disparities by sex, race, and education level, highlighting the spread of hemp-derived cannabinoids.
A 12-month study of 223 adults with chronic pain found medical cannabis was not associated with improvements in ADHD symptoms, including in those with moderate or severe symptoms, countering popular claims about cannabis as an ADHD treatment.
Lab 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.
A 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.
Data 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.
Survey of 1,335 Brazilian medical cannabis patients identified five distinct typologies, with mental health patients forming the largest group (36%), followed by pain relief (24.3%) and neurological conditions (17.8%).
Cannabis 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.
A PRISMA-guided review of 17 studies identified key perioperative risks for chronic cannabis users, including increased heart attack risk, higher opioid needs, bronchospasm, and anticoagulant interactions.
Longitudinal study of 715 Dutch adolescents found childhood trauma predicted earlier and faster-escalating cannabis use from age 16 to 22, but stress physiology differences did not explain the connection.
Analysis of 1,695 poison control reports found child cannabis exposures requiring medical attention increased significantly after California legalization, with 83.5% involving edibles, most in children under 5 at home.
Analysis of 78,678 German adults over 26 years found cannabis use odds increased roughly 9-fold from 1995 to 2021, with 800-fold differences between older and younger birth cohorts, and steep decline with age.
National survey of 1,000+ law enforcement agencies found cannabis enforcement was consistently less common than alcohol enforcement, with minimal difference between legal and nonlegal cannabis states.
Latent class analysis of 563 German cannabis-using drivers identified three distinct risk profiles: low risk (48%), DUIC-specific risk (30%), and global risk (22%), suggesting tailored prevention approaches are needed.
Analysis of 301 cannabis use disorder inpatients found 89.4% were taking drugs that could interact with cannabis, with opioid substitution therapies posing the greatest interaction risks.
Urine drug screening of 43,553 first-time jail arrestees across 25 U.S. counties found cannabis in 69% of positive screens, frequently combined with stimulants and opioids, highlighting polysubstance patterns in carceral settings.
Randomized trial of 238 adolescents found that four weeks of cannabis abstinence improved inhibitory control compared to continued use, with abstinent users performing similarly to non-users by the end of the study.
Review found medical cannabis produces modest pain relief (0.43-0.70 points on a 10-point scale) compared to placebo, with rare serious side effects but a 29% risk of cannabis use disorder, plus important medico-legal considerations.
Study of 80,018 Colombian students found marijuana use was associated with higher aggression, but polydrug involvement and the order of drug initiation were stronger predictors, complicating simple causal narratives.
CBD 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.
Review describes the three phases of Cannabis Hyperemesis Syndrome in youth (prodromal nausea, severe vomiting, recovery), emphasizes frequent misdiagnosis, and calls for educational interventions in schools and healthcare settings.
Meta-analysis of 17 studies (1.9 million people) found cannabis use associated with 48% higher risk of composite cardiovascular events, though individual associations with heart attack and stroke alone did not reach statistical significance.
PATH Study analysis of 8,218 cigarette smokers found cannabis co-use (reported by 36%) was associated with 19% lower odds of quitting smoking and 25% lower odds of quitting all combustible tobacco.
Four cannabis terpenes (geraniol, linalool, beta-caryophyllene, alpha-humulene) relieved post-surgical and fibromyalgia pain in mice through adenosine A2a receptors, suggesting a non-cannabinoid pathway for pain treatment.
Phase 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.
Analysis of NSDUH data found recreational legalization increased women's cannabis use more than men's, narrowing the gender gap, while daily use and cannabis use disorder did not increase for either gender or for youth.
Study of 197 mother-child pairs found prenatal insecticide exposure (not cannabis itself) was the primary predictor of altered child behavior, but cannabis exposure modified the insecticide-tobacco mixture effects in sex-specific ways.
NLP analysis of 13,025 adolescent health records found mood instability predicted cannabis use in both ADHD (61% higher odds) and depression (38% higher odds), with the association stronger in ADHD.
CBD 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.
First comprehensive pharmacokinetic study found delta-8 THC has 3% oral bioavailability in rats with rapid absorption, extensive tissue distribution, and extrahepatic clearance pathways.
Three weeks of a drug that boosts brain endocannabinoid levels restored motor learning and synaptic plasticity in Huntington's disease mice, suggesting the endocannabinoid system as a therapeutic target for early HD symptoms.