Childhood Trauma Combined With Cannabis Use Dramatically Amplifies Psychosis Risk ↗
Review of 62 studies found childhood trauma plus cannabis use amplified psychosis risk up to 31-fold, with earlier onset and worse outcomes than either factor alone.
Research library — page 114
Browse more cannabis research, findings, methods, and limitations.
Cannabis Use Significantly Increases Suicide Risk in First-Episode Psychosis Patients ↗
Review of 50 studies found cannabis nearly tripled suicide risk in first-episode psychosis patients, with dose-dependent effects and identified high-risk intervention windows.
Synthetic Cannabinoids Carry 4-5 Times Higher Psychosis Risk Than Natural Cannabis ↗
Systematic review of 85 studies found synthetic cannabinoids carry 4-5x higher psychosis risk than cannabis, with a distinct clinical syndrome termed "spiceophrenia."
Continuing Cannabis After First Psychosis Led to Worse Depression, More Psychotic Symptoms, and Higher Suicide Risk ↗
Patients who continued cannabis after first psychotic episode had dramatically worse depression, 3x higher relapse rates, persistent suicidality, and no functional improvement over 9 months.
How Cannabis Triggers Psychotic-Like Experiences in Otherwise Healthy People ↗
Systematic review of 38 studies finds high-potency cannabis, genetic predisposition, and environmental stressors interact to drive psychotic-like experiences in otherwise healthy people, with evidence of a bidirectional relationship.
Adding Antioxidants to CBD Boosted Its Anti-Aggression and Antidepressant Effects in Stressed Mice ↗
Combining 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.
High-Intensity Exercise Did Not Repair Brain Changes From Cannabis Use Disorder ↗
Rigorous RCT found 12 weeks of high-intensity exercise did not improve brain structure or mental health in cannabis use disorder, though 80% of participants completed the program and exercise reduced cravings.
New Dataset Captures How Differently Each US State Regulates Cannabis ↗
New dataset tracks 36 cannabis policy indicators across all 50 US states from 1994-2023, organized into pharmaceutical, permissive, and fiscal dimensions scored 0-100.
Marijuana Use Linked to 77% Higher Depression Risk in Black Male College Students ↗
Analysis of 1,599 Black male college students found recent marijuana use associated with 77% higher odds of moderately severe to severe depression, compounded by financial stress and racial discrimination.
Cannabis for Autism: Systematic Review Finds Very Limited Evidence From Clinical Trials ↗
Systematic 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.
Oral CBD and THC During Pregnancy Both Harmed Fetal Development in Mice ↗
Mouse 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.
Major Review: High-THC Cannabis Products Tied to Psychosis and Addiction, Mixed Results for Anxiety and Depression ↗
Annals of Internal Medicine review of 99 studies (221K participants) finds high-THC cannabis consistently associated with psychosis and addiction, with mixed results for anxiety and depression depending on therapeutic context.
Toddler Developed Status Epilepticus After Eating Cannabis Edibles ↗
First reported case of status epilepticus in a toddler from confirmed cannabis edible ingestion, requiring intubation and five-day hospitalization before full neurologic recovery.
Inside India's Unregulated Cannabis Market: A 13-Year User's Call for Safety Testing ↗
Drawing on 13 years in India's prohibited cannabis market, a researcher argues the real risks come from unregulated product contamination and unpredictable potency, not cannabinoids themselves.
Can Medical Cannabis Help With Anxiety Disorders? A Systematic Review of 57 Studies ↗
Systematic 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.
What's Actually on Delta-8 THC Product Labels? A Packaging Analysis ↗
Analysis of 140 delta-8 THC products found most lack health warnings and many don't clearly state cannabinoid content, highlighting gaps in an unregulated market.
Inhaled Cannabis for Diabetic Nerve Pain: A 5-Year Follow-Up Study ↗
Five-year observational study of 52 patients found inhaled cannabis associated with dramatic pain reduction (9.0 to 2.0) in treatment-resistant diabetic neuropathy, plus opioid-sparing effects.
People With Eating Disorders Rate Cannabis and Psychedelics as Most Helpful for Their Symptoms ↗
Survey 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.
CBD Reversed Memory Problems and Brain Cell Damage in a Mouse Model of Schizophrenia ↗
CBD reversed memory deficits, restored protective brain cells, and reduced neuroinflammation in a mouse model of schizophrenia, working through serotonin and cannabinoid receptor pathways.
Activating CB2 Receptors While Blocking Dopamine D4 Reduced Binge Eating More Than Either Alone in Mice ↗
Mouse study found that combining a CB2 cannabinoid receptor activator with a dopamine D4 blocker reduced binge eating more effectively than the dopamine blocker alone.
Combining Endocannabinoid Boosters With Anti-Inflammatory Drugs Reduced Post-Surgical Pain in Mice ↗
Mouse study found that boosting endocannabinoids via MAGL inhibition reduced post-surgical pain through CB2 receptors, with additive benefit when combined with an NSAID at sub-threshold doses.
How Genetics and Environment (Including Cannabis) Combine to Influence Psychosis Risk ↗
Study of 573 psychosis cases found genetic and environmental risks (including cannabis) act independently, with schizophrenia-spectrum disorders driven more by genetics and affective psychosis by environment.
Cannabis Use Linked to Lower Inflammation Markers in People Who Use Methamphetamine or Have HIV ↗
Cross-sectional study found past-month cannabis use associated with lower inflammatory markers in blood, especially among people with methamphetamine use history.
How Cannabis Affects Men and Women Differently: A Scoping Review ↗
Scoping review highlights growing evidence that cannabis affects males and females differently, with sex-based variations in sensitivity, tolerance, withdrawal, and behavioral outcomes.
Childhood Trauma Predicts Cannabis Use in New Mothers, But Resilience May Help (Up to a Point) ↗
Longitudinal study found childhood trauma predicts cannabis use in new mothers, with resilience protective at low-to-moderate trauma but losing its effect at high trauma levels.
Psychedelic Experiences Linked to Reduced Cannabis Use and Greater Psychological Flexibility ↗
Retrospective survey of 152 cannabis users found significant psychedelic experiences associated with reduced cannabis use, with 'mystical' quality predicting greater reductions.
FAAH Gene Expression Altered in Chronic Migraine Patients, Linked to Psychiatric Symptoms ↗
Small study found FAAH, the enzyme that breaks down endocannabinoids, is specifically altered in chronic migraine patients, with changes correlating to headache severity and psychiatric symptoms.
Could the Endocannabinoid System Explain Why Different Depression Treatments All Work? ↗
Narrative review proposes the endocannabinoid system as a unifying mechanism behind diverse treatments for treatment-resistant depression, from brain stimulation to psychedelics.
CBD Nanoemulsion Reduced Both Anxiety and Panic Responses in Rats at Lower Doses ↗
CBD 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.
What Do Patients Actually Think About Medical Cannabis? A Review of 40 Qualitative Studies ↗
Scoping review of 40 qualitative studies found patients generally report positive medical cannabis experiences but face stigma, costs, and a disconnect with cautious medical providers.
Two-Thirds of Danish Medical Cannabis Patients Report Moderate to Large Benefits ↗
Danish nationwide survey found 67% of medical cannabis patients report moderate to large benefits, but side effects are common and unrelated to perceived treatment effect.
Medical Cannabis Users Report Lower Quality of Life Than Non-Users With the Same Conditions ↗
Large Danish survey found medical cannabis users had lower quality of life (0.44) than non-users (0.74) with the same conditions, likely reflecting that sicker patients are more likely to try cannabis.
Nearly a Third of German Cannabis Users Experience Stigma About Their Use ↗
Pre-legalization German survey found nearly a third of regular cannabis users experienced external stigma, with medical users and those with use disorder most affected.
A 16-Year-Old's Recurrent Vomiting Turned Out to Be Cannabis Hyperemesis Syndrome ↗
Case report of a 16-year-old with two years of unexplained recurrent vomiting finally diagnosed as cannabis hyperemesis syndrome, emphasizing the need for CHS awareness in pediatric care.
Fitter Adults With Depression Have Lower Endocannabinoid Levels in Their Blood ↗
Study of 80 adults with depression found higher physical fitness associated with lower resting plasma endocannabinoid levels, suggesting a more regulated system.
Legal and Illegal Cannabis Prices Are Converging Five Years After Canadian Legalization ↗
Five years after Canadian legalization, 78% of cannabis purchases come from legal sources, with price gaps narrowing though legal dried flower still costs 24% more.
Only 1 in 10 Cannabis Users Seek Help for Problems, and Most Go to a Doctor First ↗
Survey found only 9.2% of cannabis consumers sought help for problems, with doctors most common in legal jurisdictions and family/friends preferred where cannabis is illegal.
Pre-Transplant Cannabis Use Linked to Higher Immediate Opioid Needs But No Worse Liver Transplant Outcomes ↗
Study of 4,236 liver transplant patients found cannabis users needed slightly more opioids initially but had no differences in length of stay, readmission, or mortality.
Who Downloads an App to Take a 30-Day Break From Cannabis? ↗
Analysis of 4,415 cannabis break app users found they were predominantly young daily users seeking mental clarity, with most planning to reduce rather than quit entirely.
CBD Oil Combined With Orphenadrine Dramatically Reduced Pain in a Patient With Mast Cell Activation Syndrome ↗
Case report shows 87% reduction in pain interference for a mast cell activation syndrome patient treated with CBD oil and orphenadrine over 20 weeks.
Daily Inhaled Cannabis Linked to Higher Odds of Asthma and COPD in Nearly 380,000 Adults ↗
Analysis of 379,049 adults found daily inhaled cannabis associated with 44% higher asthma odds and 27% higher COPD odds, persisting after tobacco adjustment.
CBD in Skincare and Dermatology: What the Science Shows So Far ↗
Review finds CBD shows promise for acne, psoriasis, eczema, and other skin conditions through the skin's endocannabinoid system, though formulation challenges remain.
Prenatal Cannabis Exposure Alone Didn't Predict Child Maltreatment After Policy Changed ↗
Study of 35,437 births found prenatal THC exposure alone did not predict maltreatment after policy stopped automatically substantiating it as abuse, and revealed racial bias in testing.
Eating a High-Fat Meal Increases CBD Absorption by Nearly 10-Fold ↗
Crossover trial found eating a high-fat meal increases CBD absorption by nearly 10-fold, with peak blood levels 17 times higher compared to fasting.
CBD Reduced Depression-Like Behavior and Brain Inflammation in Female Rats Exposed to Stress and a High-Fat Diet ↗
CBD reduced depressive behaviors and brain inflammation in female rats exposed to both obesity and chronic stress, with effects depending on the type of stressor.
Cannabis Increases Spontaneous Mind-Wandering and Impairs the Ability to Control It ↗
Controlled study found cannabis significantly increases spontaneous mind-wandering and impairs the ability to regulate attention in regular users.
Cannabis and Mental Health: Why Results Seem Contradictory and What Actually Matters ↗
Review explains why cannabis-mental health findings seem contradictory: it depends on THC vs CBD content, use frequency, age, genetics, and other often-overlooked factors.
CBD at 50mg or 300mg Did Not Improve or Impair Running Performance in Trained Athletes ↗
Rigorous crossover trial found CBD at 50 mg and 300 mg did not improve or impair running performance, mood, or perceived exertion in trained athletes.
How the Brains of People Seeking Cannabis Use Disorder Treatment Respond to Cannabis Cues ↗
fMRI study of 65 treatment-seeking CUD patients found increased brain activation to cannabis cues in executive and reward regions, with an unexpected inverse relationship between craving and reward area activation.
A Gene That May Determine Who Gets Psychosis From Cannabis ↗
A genetic variant in the cannabinoid receptor 1 gene (rs1049353) differed in frequency between cannabis users who developed psychosis and those who didn't.