Browse more cannabis research, findings, methods, and limitations.
A schizophrenia patient hospitalized 30 times in 8 years reported significantly less need for illegal cannabis and no further hospitalizations after switching to low-THC CBD cigarettes.
A study of 101 low-income pregnant women found sexual partner violence predicted marijuana use during pregnancy, while physical violence and childhood adversity predicted cigarette use at different intensity levels.
Among 33,343 US stress cardiomyopathy admissions, 210 marijuana-related cases were younger, had fewer traditional risk factors, but experienced more cardiac arrest, respiratory failure, and cardiogenic shock.
About 25% of marginalized drug users in Vancouver reported using cannabis to reduce harm from other substances, most commonly as a substitute for stimulants and opioids.
Two controlled studies found cannabis reliably increased psychotic-like symptoms, but CBD in the cannabis did not reduce these effects. Adolescents were actually less vulnerable to acute psychotic effects than adults.
A study of 441 adolescents with chronic kidney disease found cigarette smoking worsened proteinuria, but marijuana, alcohol, and e-cigarette use were not associated with kidney disease progression.
Review of whole-plant cannabis and sleep found effects depend on dose, strain, and delivery — with vaporized high-THC cannabis promoting deep sleep in animals.
A study of 605 young adolescents (mean age 13) found cannabis users scored much higher on hopelessness, depression, and anomalous reality perception, with hopelessness being the strongest unique predictor of use.
Analysis of 1,110 digital cannabis assessments found higher problem scores and polysubstance use predicted driving after cannabis use, with the tool costing under a dollar per use.
CBD prevented anxiety, memory loss, and depressive behavior after brain ischemia in mice, working through four different receptor systems including CB1, CB2, serotonin, and PPAR-gamma.
Inhaled cannabis reduced eye pressure by 16% in healthy adults, with the effect strongly correlated to plasma THC levels up to 20 ng/ml but plateauing beyond that threshold.
A study of 20 breastfeeding mothers found THC concentrated in breast milk at 7 times plasma levels, with mothers increasing cannabis use in the early postpartum period.
A survey of 100 IBD patients in Puerto Rico found 27% used cannabis, most had limited knowledge, 78% had not told their doctor, and 68% reported symptom improvement.
A large genetic study found significant positive correlations between anorexia nervosa and both cannabis initiation and cannabis use disorder, with substance-specific patterns suggesting complex shared biology.
Children exposed to marijuana before birth showed more sleep problems, withdrawal symptoms, and aggressive behaviors at age 3.5 compared to non-exposed children, but executive function was not affected.
A study of 40 cannabis-dependent patients found significant psychiatric symptoms but no changes in thyroid hormones or cardiovascular measures compared to controls, suggesting tolerance to some but not all effects.
A double-blind trial of 56 Crohn's patients found CBD-rich cannabis oil improved symptoms and quality of life but did not change endoscopic scores or inflammatory markers, raising questions about symptom masking.
A study of 2,335 opioid use disorder patients found that current cannabis use was associated with 41% higher odds of suicidal ideation, adding complexity to the cannabis-for-opioid-harm-reduction narrative.
THC and CBD both inhibit the liver enzymes that process most prescription drugs — meaning cannabis can effectively increase your medication doses. Even THC metabolites cause inhibition, extending the interaction window.
Interviews with 97 cannabis users in Nigeria found that abstinence-only recovery frameworks led to feelings of failure after relapse, prompting some to redefine recovery as a process of reduced use and improved well-being.
A survey of 417 German IBD patients found 4.3% used cannabis for their condition, with most reporting benefits but over half obtaining cannabis from the black market rather than through medical channels.
A 30-day daily diary study found sexual minority young adult smokers had 2-3 times the odds of same-day cigarette-cannabis and triple substance use compared to heterosexual peers.
An fMRI study of 74 young adults found that depression and cannabis use each independently altered brain activation during emotion regulation, but in different temporal lobe regions.
In a Danish cohort of 1,632 children, early cannabis use by age 15 was the strongest independent predictor of subclinical hypomania at age 16, with a 3-fold increased risk.
Systematic review finds FAAH plays a role in alcohol use disorder biology, with inhibition reducing withdrawal symptoms but potentially increasing alcohol preference.
Meta-analysis of 17 studies finds uncertain evidence for cannabis reducing opioid use, with RCTs showing little effect on pain and increased nausea and vomiting.
Analysis of 85 Maryland dispensaries found no racial or income disparities in geographic placement, with dispensaries located in racially diverse, retail-dense areas.
Scoping review of 6 studies finds preliminary positive signals for cannabis in IBD, but evidence is too limited for clinical recommendations.
Review links cannabis use to increased cardiovascular risk, including nearly 5x higher MI risk, particularly affecting younger men immediately after consumption.
Small crossover trial finds CBD increases hippocampal glutamate in psychosis patients, correlating with reduced symptom severity.
fMRI study finds single CBD dose partially normalizes altered brain activation in psychosis patients toward patterns seen in healthy controls.
Animal study finds the synthetic cannabinoid MMB-Fubinaca produces stronger effects in males than females, all through CB1 receptors.
Review finds cannabis metabolic pathways overlap with transplant drugs, creating risks of unstable immunosuppression, graft failure, and infection in heart transplant recipients.
Meta-analysis of 8 national surveys finds cannabis use disorder is associated with 3x higher odds of major depression and generalized anxiety disorder.
Survey of 145 Colombian psychiatrists finds strong support for medical cannabis availability but low confidence in legal access knowledge, with most disapproving its use for psychiatric conditions.
Comparative study finds cannabis-induced psychosis and schizophrenia have distinct symptom profiles, with different patterns of speech and thought disorder.
Drug seizure analysis finds marijuana seizures dipped during early COVID then surged past pre-pandemic levels by August 2020, while fentanyl seizures rose continuously.
Qualitative study of 50 young SGM men finds cannabis used to manage anxiety during sex, substitute for harder drugs, and self-treat depression, with some experiencing adverse effects.
Rat study finds CB2 receptor activation with AM1241 protects against bleomycin-induced lung fibrosis by reducing inflammation and oxidative stress.
Study of 598 heavy-drinking young adults finds daily cannabis use linked to modestly poorer working memory and more impulsivity, while occasional use showed no deficits.
Study finds cannabis users show elevated neurological soft signs regardless of psychosis status, suggesting cannabinoids affect brain circuits involved in motor and sensory processing.
National analysis of 68 million hospital records finds cannabis use disorder associated with 28-52% higher odds of arrhythmia hospitalization in young adults, with atrial fibrillation most common.
Daily diary study finds simultaneous alcohol-marijuana use increases riding with impaired drivers, while non-simultaneous use of both substances most increases driving after use.
ABCD study of 11,489 children finds prenatal cannabis exposure associated with greater psychopathology, sleep problems, higher BMI, and lower cognition at ages 9-11.
Brain scan study of 408 individuals finds cannabis use frequency linked to smaller hippocampal volume, which mediated the relationship with working memory impairment.
Study across 6 Canadian managed alcohol programs finds 63% of participants already substitute cannabis for alcohol, with 84% willing to join a formal substitution program.
Review finds cannabis impairs driving skills but blood THC levels are unreliable impairment markers, arguing that cannabis driving policy has outpaced the science.
Mouse study finds CBD prevents psychosis-like behavior with effects lasting 24 hours, involving DNA methylation changes in brain regions implicated in schizophrenia.
Lab study finds specific cannabis extract fractions kill glioblastoma cells, inhibit migration and invasion, and prevent colony formation in multiple cancer models.
Study of 102 psychosis patients finds earlier cannabis use linked to altered cerebellar brain network structure previously implicated in schizophrenia.