Browse more cannabis research, findings, methods, and limitations.
National analysis of 1.6 million urologic cancer surgeries found CUD prevalence increased 7-fold (2003-2014) and was linked to 31% longer stays and 33% higher costs, but not more complications.
New Mexico study found reported prenatal cannabis use paradoxically decreased after recreational legalization, while cannabis-exposed infants continued to show worse birth outcomes in both periods.
French ER study found nearly 1 in 4 young visitors (16-25) were using cannabis, with strong associations to unemployment, sexual abuse history, and alcohol problems.
First study of drug use in Burkina Faso prisons found cannabis was the most common drug (71% of users), with one-third of in-prison users starting drug use while incarcerated.
21-country survey of 28,154 drug users found higher perceived harm from secondhand cannabis smoke was associated with 70% greater odds of not smoking cannabis at home.
US survey of 21,381 adults found perceiving secondhand cannabis smoke as "extremely harmful" was associated with 6x higher odds of banning cannabis smoking in the home.
Global Drug Survey of 64,000 cannabis users found about 64% smoked at home, with daily home smoking in roughly 25-28%, raising concerns about residential secondhand smoke exposure.
Review of the past decade of research explains how cannabis triggers psychosis by disrupting the endocannabinoid system during adolescent brain development, affecting synaptic pruning and neurotransmitter signaling.
Multicenter 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.
Scoping review of 35 studies found cannabinoids in cancer care most studied for nausea/vomiting (77%), with far less evidence for appetite, pain, and tumor effects.
NIDA leaders identify critical research gaps: effects of high-THC cannabis during brain development, therapeutic endocannabinoid system manipulation, and CUD treatment strategies.
Rat study found prenatal THC disrupted stress hormone receptors and dopamine signaling specifically in male offspring, causing stress vulnerability that was correctable with a developmental intervention.
Systematic review found cannabis smoking independently increases heart attack risk (aOR up to 5.24) after adjusting for tobacco, while non-smoked cannabis showed no significant cardiac risk.
Fibromyalgia RCT found cannabis combined with oxycodone reduced opioid intake by 35% but offered no advantage in pain or side effects, with one-third of cannabis users dropping out.
Spine surgery patients with CUD had 2.6x more readmissions and 3.4x more reoperations after neck fusion, but paradoxically fewer medical complications at 6 and 12 months.
Rat 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.
Study of 140 adults in addiction treatment found those with ADHD started substance use younger and had higher rates of cannabis, alcohol, and methamphetamine use.
Meta-analysis of 58 RCTs in adults 50+ found cannabinoid medicines increase common side effects dose-dependently but do not significantly increase serious adverse events, withdrawals, or deaths.
RCT of 1,489 university students found the Minder app significantly reduced anxiety, depression, and cannabis use frequency over 30 days, with 77% engagement.
Systematic review found only 5 RCTs on integrated treatment for psychiatric disorders in cannabis-using youth, revealing a critical gap for depression, bipolar, anxiety, and PTSD.
National study of 113,000 young adults found daily cannabis use associated with 1.7-1.8x violent behavior in males, while any cannabis use was linked to 1.6-2.4x higher odds in females.
Retrospective study found adding marijuana to tobacco during pregnancy did not produce additional adverse birth outcomes, though both groups had high rates of adverse outcomes.
Study of 225 young adults found greater cannabis use linked to small reductions in emotional processing speed and working memory, with modest age-of-onset effects but no sex differences.
Hair testing for THC metabolites in 13- to 14-year-olds revealed cognitive deficits in memory, verbal ability, and inhibitory control that self-reported cannabis use alone did not capture.
Inhaled cannabis terpenes linalool and beta-myrcene reduced anxiety in mice, but effective dosing patterns and CBD synergy differed between males and females.
Among 12- to 15-year-olds in the ABCD Study, cannabis use was linked to more depression symptoms, with the strongest association in teens who also had smaller amygdala volumes.
Medical marijuana patients reported significant relief from gastrointestinal symptoms at every survey point over a 12-month period, with mild to moderate side effects.
CBD 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.
Controlled study found eyelid tremor had only 18% specificity for detecting recent cannabis use, with trained experts unable to reliably distinguish users from non-users.
Lab analysis of vaping products from 16 California high schools found 90% of disposable vape pens contained THC or CBD, and some nicotine labels were inaccurate.
In a study of over 680,000 patients, semaglutide was associated with 40-56% lower risk of new cannabis use disorder and 38% lower relapse risk compared to other obesity and diabetes medications.
A compound from cannabis seeds called trilinolein improved eczema in mice by repairing mitochondrial damage in skin cells, performing comparably to the prescription drug crisaborole.
Review of preclinical research finds CBD extends healthspan and lifespan in model organisms through autophagy and antioxidant mechanisms, with emerging evidence against cellular senescence.
Review outlines how medicinal cannabis could protect gut mucosal barriers during cancer treatment, potentially addressing the cascade of symptoms from mucositis through the endocannabinoid system.
Data from 24 European countries shows synthetic cannabinoids cause more neurological emergencies (coma, seizures) while natural cannabis is linked to cardiovascular symptoms (tachycardia, chest pain).
Large pandemic-era cohort found prenatal cannabis exposure linked to a borderline increase in communication delays at 12 months that did not survive statistical correction, with no effects on birth outcomes or other developmental domains.
Small 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).
Expert 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.
PET 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.
Cannabis use was the only substance independently linked to lower grades, truancy, and detention in teens, with significantly stronger associations among adolescents with chronic illness.
Brain connectivity patterns linked to poor sustained attention at age 14 predicted increases in cannabis and cigarette use through age 23, suggesting attention deficits precede substance use.
Analysis across four studies found that shifts toward using cannabis for multiple motives predicted worse outcomes, offering a foundation for adaptive, personalized interventions.
National survey of 14- to 24-year-olds found most believe cannabis is harmful during pregnancy and want clinician counseling, though over one-third would classify prenatal use as child abuse.
First systematic comparison finds glass pipes release about 80% of radioactive polonium-210 from cannabis, while water pipes release about 40% and filters absorb some contamination.
Interviews with 20 psychiatric hospital staff found cannabis legalization improved some aspects of care but increased use, complicated mental health treatment, and exposed gaps in provider training.
After ER visits for cannabinoid hyperemesis syndrome, patients had persistent symptoms for a week and most resumed cannabis use within days, with 25% returning to the ER within three months.
Survey of 23,500 New Zealand cannabis users found 60% reported using less alcohol due to cannabis, with substitution patterns varying by age, ethnicity, and urban/rural location.
In a study of over 558,000 teen surgical patients, those with cannabis use disorder had 2.4x higher risk of needing mechanical ventilation and nearly 2x the risk of ICU admission.
Synthetic 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.
Updated 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.