Browse more cannabis research, findings, methods, and limitations.
A systematic review found strong biological rationale and patient reports supporting cannabinoids for Tourette syndrome, but only two small trials exist, leaving efficacy and safety largely undetermined.
A 25-year-old developed delayed brain hemorrhage days after synthetic cannabinoid use, despite an initially normal brain CT, highlighting the risk of late intracranial complications.
A survey of nearly 6,000 adults found 2.2% had functional vomiting disorders, with all cannabinoid hyperemesis cases in the US and hot water bathing for symptom relief augmented by cannabis use.
A survey of 1,000 Colorado recreational dispensary customers found 65% used cannabis for pain and 74% for sleep, with most reporting they reduced or stopped using other medications including opioids.
Focus groups with 37 cannabis-using teens identified rewards, self-monitoring, peer support, privacy, and customizable notifications as key elements for an engaging cessation app.
A 16-patient cohort with bleeding from rat poison-contaminated synthetic cannabinoids showed 75% had severely abnormal clotting, one died, and treatment averaged $5,300 per hospitalization.
A comprehensive review of THC covers its pharmacology as a CB1 partial agonist, approved uses for pain and nausea, and ongoing debates about psychosis risk, cognitive effects, and addiction potential in 192 million users worldwide.
In 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.
A comprehensive review details how alcohol alters the endocannabinoid system to drive addiction, how CB1 receptors contribute to alcohol reward, and how ECS disruption contributes to fetal alcohol spectrum disorders.
A review distinguishes the endocannabinoid system's role in alcohol addiction (CB1 in reward circuits) from its role in fetal alcohol disorders (developmental ECS disruption), suggesting different therapeutic targets.
A 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.
A review of 27+ jurisdictions found wide variation in home cannabis cultivation policies and argues they could serve as a foundation for community-level supply models.
High-sensitivity testing found 25% of urban teens positive for THC, far more than standard tests detected. Cigarette smokers had 13x the odds of marijuana use.
Beta-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.
An RCT found weekly text messages to parents about school performance reduced teen alcohol and marijuana initiation from 18.2% to 10.2% by 8th grade, at just $15/student/year.
Cyclic vomiting hospitalizations in Colorado rose 46% from 2010-2014 alongside rising cannabis use after legalization, with CVS patients 8-10x more likely to use cannabis than other patients.
AKB48 stimulated dopamine reward pathways at low doses but caused hypothermia, catalepsy, and cardiac depression at higher doses, with all effects mediated through CB1 receptors.
Epidiolex 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.
Cannabis users with two copies of a specific FAAH gene variant had 10x higher odds of a first psychotic episode, identifying a gene-environment interaction that could explain selective psychosis risk.
A 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.
An fMRI study found adolescent cannabis use disorder was linked to reduced brain activation in threat-processing regions including the amygdala, an effect not seen with alcohol use disorder.
A meta-analysis found altered brain network function in teen cannabis users even after 25+ days of abstinence, when cognitive test performance had already recovered.
A review of 40 studies found chronic cannabis use consistently increases cerebellar gray matter volume, alters resting brain activity, and impairs memory and decision-making.
A review found increasing pediatric hospitalizations from high-potency cannabis products like edibles, causing sedation and respiratory depression in young children, while chronic teen use causes cognitive and GI problems.
A comprehensive neuroimaging review found cannabis affects executive, emotional, reward, and memory brain systems through direct and indirect pathways, with adolescent use carrying particular risk for lasting changes.
Focus groups with 136 Colorado adults over 60 found older adults want cannabis education from providers but stigma and lack of research prevent meaningful conversations about use.
A survey of 1,321 chronic pain patients found 80% substituted cannabis for traditional pain meds, including 53% for opioids, citing fewer side effects and better symptom control.
A survey of 1,321 chronic pain patients found wide variability in cannabis preferences by sex and experience, with only 2.6% receiving medical professional guidance on product selection.
Among young adults with psychosis, cannabis users and non-users showed no cognitive differences at illness onset, suggesting cannabis may trigger psychosis in individuals who would not otherwise develop it.
A 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.
THC increased brain activity in attention and salience networks, with the COMT gene variant determining how executive networks responded, linking dopamine genetics to cannabis susceptibility.
Cannabis use predicted suicidal ideation, planning, and attempts in 451 Latinx LGB teens, with the strongest association (OR 3.12) for actual suicide attempts.
Prenatal cannabinoid exposure in rats accelerated early motor development but worsened alcohol-related motor impairment specifically in females, with combined exposure showing complex interactions.
A systematic review of cannabis pharmacology in cancer found only 18 relevant studies and virtually no absorption data, revealing a critical gap in dosing knowledge for this patient population.
A prospective study of 3,005 injured drivers found no crash risk increase with THC below 5 ng/mL and only a non-significant increase above, compared to sixfold increase for alcohol above 0.08%.
Adolescent cannabis smoke and THC exposure in rats produced no lasting anxiety, depression, or cognitive effects in adulthood, suggesting human associations may involve non-cannabinoid factors.
A randomized trial found online responsible vendor training for marijuana stores improved ID checking skills and intoxication detection confidence, with 91% of employees recommending it.
A review found substantial evidence that cannabis affects brain structure and cognition, particularly during adolescence, while paradoxically some cannabinoid compounds are approved for medical use in children.
A 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.
A study of 86,254 teens across 21 countries found cannabis use approximately doubled the odds of suicide attempts, with the association consistent across countries with widely varying cannabis prevalence.
A review for pediatric gynecologists found adolescent marijuana use carries risks for brain development, reproductive health, and mental health, with limited research on gynecological-specific effects.
A synthetic marijuana user developed severe blood clotting failure and cardiac arrest from brodifacoum (rat poison) contamination, adding to evidence of a contamination crisis.
Follow-up potency monitoring found cannabis THC doubled to 17.1% by 2017, concentrates hit 55.7%, and the THC:CBD ratio reached 104:1 in both U.S. and European markets.
A review found cannabis smoke can trigger asthma attacks and allergic reactions, with users showing more symptoms and medical visits, making cannabis an underrecognized respiratory disease trigger.
A heavy cannabis user developed Wernicke's encephalopathy (brain damage from thiamine deficiency) after severe vomiting from cannabis hyperemesis, a complication usually associated with alcoholism.
A review found CBD shows therapeutic potential across autism, anxiety, psychosis, pain, epilepsy, and neurodegenerative diseases, with mainly diarrhea and somnolence as side effects.
Epidiolex (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.
Cannabis-related pediatric ER visits are rising, ranging from accidental ingestion (hyperkinesis, coma in young children) to chronic hyperemesis and psychosis in adolescents.
Past-year marijuana use nearly doubled among former US cigarette smokers from 2002-2016, while depression and binge drinking also rose, threatening sustained smoking cessation.
Among 12,642 teens, bullies and bully-victims had higher marijuana use, but stronger parent and peer attachments significantly reduced this risk, suggesting targets for prevention programs.