Browse more cannabis research, findings, methods, and limitations.
Meta-analysis of 26 RCTs found cannabinoids beat placebo for chemo nausea, but nearly all studies predate modern antiemetics, leaving their current role unclear.
Study of 17,423 COVID-19 patients found cannabis and other substance use linked to more ICU admissions and longer hospitalizations but not increased death rates.
Pilot RCT found vortioxetine improved clinician-rated mood in cannabis users over 6 months but did not reduce cannabis dependence or self-reported mood symptoms.
National survey of 70,000 US adolescents found cannabinoid vaping increased across all types from 2021-2023, with 2.55 million teens vaping THC and synthetic cannabinoid use doubling among youngest students.
Meta-analysis of 31 studies found male, older, White adolescents who use alcohol or tobacco had the highest odds of vaping cannabis, with Black adolescents having lower odds.
Among 7,178 cannabis users, dual-use (vaping + smoking) was linked to severe externalizing symptoms, while vaping-only was more common among White, higher-income adults.
Meta-analysis of 81 million participants found cannabis use associated with 71% higher atrial arrhythmia risk, with concurrent drug use and legal country status further increasing risk.
Parents of children with sickle cell disease expressed concerns about medical marijuana similar to their concerns about opioids, with societal stigma as a major barrier to treatment acceptance.
Interviews with 40 US teens found most viewed cannabis as more acceptable than alcohol, citing alcohol's worse health effects, higher addiction risk, and more aggressive intoxication.
Survey of 935 people found dispensary proximity weakly correlated with medical cannabis attitudes, with gender and state legal status being stronger predictors than physical proximity.
Lab and modeling study found THC and CBD inhibit the enzyme that metabolizes hydromorphone, predicting a 20-30% increase in opioid exposure when cannabis and hydromorphone are used together.
Among 868 HIV-positive cannabis users in legal Ontario, only 14% held medical authorization, with medical users reporting worse physical health, more symptoms, and more frequent therapeutic-style use.
A 45-year-old with 20 years of daily marijuana use required three vascular bypass surgeries for severe PAD despite having no diabetes, hypertension, or hyperlipidemia.
Analysis of 21.9 million Arizona hospital visits found cannabis-related visits were ~7 times more likely to involve psychosis, a stable pattern from 2016 to 2022.
Survey found 33% of people with hair-pulling or skin-picking disorders used cannabis in the past year, and users had more frequent symptoms and greater distress.
Systematic review found 15 Canadian youth DUIC prevention initiatives since legalization, but limited evidence that any changed actual driving behavior.
Pilot RCT of a smartphone app for youth cannabis-impaired driving showed positive reception and preliminary efficacy, but faced significant recruitment and retention challenges.
Mouse study found that CBD exposure during pregnancy or nursing decreased pup survival and caused lasting sex-dependent changes in behavior and metabolism.
Review found CBT and motivational therapy improve cannabis use outcomes short-term, but effects typically fade by nine months. No medications are approved for cannabis use disorder.
Analysis of 214,505 U.S. adults found cannabis use clustered with heavy drinking, tobacco, and obesity in distinct gender-specific patterns, concentrated in younger and higher-income groups.
Experiment with 2,523 young adults found copycat cannabis packaging reduced correct identification by 65%, highlighting accidental ingestion risks.
Experiment with 4,500 young adults found plain cannabis packaging boosted warning recall by 47% and reduced appeal, while health claims on packages increased appeal.
Interviews with 24 CHS patients found that positive beliefs about cannabis led many to contest their diagnosis and try alternative use patterns rather than abstaining.
Study of 93 older adults found cannabis smoking linked to thousands of epigenetic changes, mostly persisting after quitting, concentrated in cancer and aging pathways.
Mouse study found repeated JWH-018 exposure progressively increased hyperactivity and aggression through CB1 and dopamine pathways, with brain receptor changes.
Study of 70 adolescent smokers found daily cannabis users wanted more cigarettes but were more sensitive to price increases than non-cannabis users.
Pilot trial with 101 young adults with psychosis found a digital cannabis harm reduction app was feasible (82% retention) and showed early signals of benefit.
35-year CARDIA study of 4,328 adults found no association between cumulative cannabis use and developing hypertension, with results robust across sensitivity analyses.
ALSPAC study of 15,013 families found prenatal cannabis-outcome links were largely explained by confounding, since paternal cannabis use showed similar associations.
Pooled analysis of 684 cancer patients found cannabinoid use during dual immunotherapy was safe and associated with improved progression-free survival by one measure.
Rat study found a standardized cannabis extract at doses up to 56 mg/kg had no significant effects on fertility, hormones, sperm quality, or early embryo development.
Cross-sectional study of 82 methadone patients found childhood trauma correlated with greater pain, more alcohol use, and earlier cannabis initiation.
In a zebrafish autism model, CBD reversed hyperactivity and aggression more effectively than risperidone and normalized underlying neurobiological markers.
A cannabis harm-reduction app co-designed with young adults scored 4.43/5.0 on usability and is now being evaluated for efficacy.
34 severe poisonings in New Jersey linked to gas station tianeptine products adulterated with synthetic cannabinoids. 43% required intubation.
Rodent brain study reveals stress hormone corticosterone triggers endocannabinoid (2-AG) production in a pain-control region, reducing inhibitory GABA signaling through CB1 receptors.
Parents are increasingly giving children unregulated CBD products despite FDA approval only for specific epilepsy — with concerns about product quality, drug interactions, and absent pediatric evidence.
Synthetic cannabinoids found in vapes at 78% of 27 English secondary schools tested, with prevalence tied to socioeconomic deprivation.
Seven disposable vapes sold as cannabis in the UK all contained synthetic cannabinoid 5F-MDMB-PICA at 0.85 mg/mL median, with zero natural cannabinoids.
345 healthcare trainees across four disciplines completed a cannabis education program; 96% reported improved ability to counsel patients.
Neonatal MRI found lower total brain volume in infants exposed to cannabis in utero — in a carefully controlled study excluding alcohol, tobacco, and other drug exposure.
Mouse study finds CB1 receptors on dopamine neurons in the VTA-to-NAc circuit link trait anxiety to enhanced reward learning.
Survey of 4,031 young adults found cannabis-using parents nearly tripled their odds of using cannabis.
Study of 1,359 young adult cannabis users identified four spending profiles. Higher-spending groups reported more problematic use.
European longitudinal study finds genetic risk for cannabis use disorder is associated with impulsivity, novelty seeking, and white matter brain changes as early as age 14.
Pilot trial with 6 sickle cell patients showed dronabinol for pain is feasible and safe. A larger parallel trial is underway.
Longest cannabinoid trial in Alzheimer's: 26 weeks of very low-dose THC-CBD extract showed significantly higher cognitive scores vs placebo.
Survey of 1,721 medical cannabis patients shows widespread use of delta-8 THC, THCA, CBG, and CBN. Most reported stopping at least one pharmaceutical.
Among 63,713 insured epilepsy patients, 1.1% had cannabis use disorder. Young adults 18-24 were at 5x the risk.
In rat migraine models, CBD combined with 0.3% THC provided the longest pain relief and was the only treatment reducing light sensitivity.