Browse more cannabis research, findings, methods, and limitations.
About 9-10% of participants in a U.S./Mexico border community had tried synthetic cannabinoids or Salvia, with current marijuana use being the strongest predictor.
Swedish monitoring detected over 50 different new psychoactive substances in emergency patients, predominantly young males, with synthetic cannabinoids among many diverse classes.
Smokers who used marijuana and other drugs expected quitting cigarettes would cause adverse outcomes, reducing their quit motivation across all six substance categories tested.
A 21-year-old regular cannabis user had a heart attack with normal arteries, confirmed by intravascular ultrasound, suggesting cannabis can trigger clotting without underlying arterial disease.
A patient with chronic vomiting previously diagnosed as cyclic vomiting syndrome was found to have cannabinoid hyperemesis syndrome, highlighting the importance of cannabis screening.
A selective endocannabinoid enzyme blocker (KML29) reduced inflammatory and nerve pain in mice without cannabis-like side effects like sedation or immobility.
Among 9,288 Ontario students, about 1 in 5 had a history of brain injury, which was linked to cannabis use, mental health problems, and risky behaviors with sex-specific patterns.
Cannabis-dependent veterans with moderate/high physical activity were less likely to relapse during the first week of quitting, especially in the first four days.
In chronic pain patients, oral THC at 10-20 mg produced psychoactive effects comparable in peak intensity to smoking marijuana, peaking at 2 hours vs. 30 minutes for smoking.
Review found cannabis crosses the placenta and enters breast milk, with evidence suggesting adverse effects on fetal brain development that may persist into adulthood.
In a randomized trial, lithium did not reduce overall cannabis withdrawal severity vs. placebo, though it improved appetite loss, stomach aches, and nightmares.
Review found regular marijuana smoking causes bronchitis symptoms and airway inflammation, while occasional use does not increase COPD risk and the cancer link remains unproven.
French national data identified 35 serious cardiovascular events in cannabis users (2006-2010), including 20 heart attacks and 9 deaths, mostly in young men.
Among Arkansas high schoolers, cannabis (33% ever use), inhalants (19%), and prescription drugs (13%) were all linked to suicidality, with prescription drug abuse showing the strongest association.
The 2013 national youth survey found 23% past-month marijuana use among high schoolers, a rate that had not changed over time despite declining cigarette use.
Cannabis-dependent men showed reduced cognitive control brain activity, and those with greater pre-treatment activation in control and reward regions used less cannabis during and after treatment.
The AAN systematic review found oral cannabis extract effective for MS spasticity and pain, but ineffective for tremor and of unknown efficacy for epilepsy (pre-CBD trials).
A 20-year-old woman with protracted nausea and vomiting from cannabis withdrawal was successfully treated with the synthetic cannabinoid nabilone.
Review of oral fluid cannabis testing found THC can exceed 1,000 micrograms/L after smoking, with detection windows varying by route, dose, and use history.
During monitored cannabis abstinence, most withdrawal symptoms peaked in days 0-3 and improved, but sleep disturbance and strange dreams got progressively worse over time.
Pilot study found that adding tobacco treatment to cannabis treatment did not harm cannabis outcomes, with 5 of 6 participants achieving cannabis abstinence.
Among 25,456 high schoolers, marijuana use was associated with twice the odds of gambling and gambling problems, alongside alcohol and prescription drug misuse.
Across 22 longitudinal cohorts, cannabis use was linked to about 29 percent higher odds of later depression, with exposure measures often weak and overall bias rated medium.
A dual enzyme inhibitor that boosts natural endocannabinoids suppressed anticipatory nausea in rats through CB1 receptor activation, with enhanced effects when combined with anandamide.
Daily cannabis users were more likely to meet hyperactive‑impulsive ADHD symptom criteria; nondaily users showed no subtype split.
Charlotte Figi: 50 seizures/day to 2-3/month on CBD cannabis extract. Single case that launched a movement, a drug approval, and a national policy shift.
Clozapine reduced cannabis craving and insula brain activity more than risperidone in patients with schizophrenia and cannabis use disorder over 4 weeks of treatment.
A large Dutch randomized trial of the Healthy School and Drugs prevention program found no significant effects on adolescent alcohol, tobacco, or marijuana use at 32 months.
Among 290 adolescents with eating disorders, nearly half of those with bulimia nervosa reported substance use, with older age being the strongest predictor of regular use.
First study examining THC dependence in both sexes of adult rats found broadly similar withdrawal signs spanning somatic, cognitive, and affective domains, with females showing more retropulsion.
Longitudinal study found marijuana use predicted dating aggression in girls, hard drug use predicted it in boys, and alcohol predicted aggression timing for both sexes across grades 8-12.
Systematic review found that exercise, massage, acupuncture, several medication classes, and lifestyle factors all upregulate the endocannabinoid system, relevant to conditions like migraine and fibromyalgia.
Study of 11 daily cannabis smokers found that oral THC (dronabinol) increased blood cannabinoid levels dose-dependently, but smoked cannabis was only distinguishable from oral THC for about 1 hour.
Positive schizotypy, not cannabis use, predicted creativity. Cannabis was only associated with divergent thinking in people who scored low on baseline creativity measures.
Pilot study found Sativex patients had oral fluid THC over 5,356 ng/mL shortly after dosing, remaining detectable for 2+ hours, with primary roadside test often giving false negatives.
RCT of 185 patients found an 8-session CBT intervention did not outperform treatment as usual for substance users with suicide risk on any measure over 6 months.
Review of early clinical data found cannabis improved Crohn's disease activity scores in small trials, but low-dose CBD alone did not work, and larger controlled studies are needed.
Population study of 1,560 young adults found lifetime crack cocaine use (2.5% prevalence) was associated with PTSD, antisocial personality disorder, suicide risk, and polysubstance use including cannabis.
CB1 receptor activation with a synthetic cannabinoid impaired memory-related brain signaling (LTP) by causing abnormal overproduction of proteins and inhibiting acetylcholine release.
Twelve-week study of 48 laying hens found hempseed (up to 30%) and hempseed oil (up to 9%) had no negative effects on performance, egg quality, or blood chemistry.
RCT of 764 students found the Climate Schools online prevention program reduced truancy, psychological distress, and moral disengagement for up to 12 months.
Pilot of the Australian Climate Schools online drug prevention program in 2 UK schools found 85% of students found it easy to understand and 82% of teachers would use it again.
Black pepper compound guineensine inhibited endocannabinoid uptake at nanomolar concentrations and produced cannabis-like effects in mice that were blocked by a CB1 antagonist.
Case report of a 32-year-old woman who developed takotsubo (stress) cardiomyopathy during an episode of cannabinoid hyperemesis syndrome after resuming marijuana use.
Canadian study found teens with ADHD reported cannabis use at 14.2%, comparable to or lower than the 16.5-26.0% rates in two general population samples.
Review found marijuana smoke causes cough and sputum similar to tobacco but does not appear to cause COPD, with mixed and unclear evidence on cancer risk.
Mouse study found acute and repeated cocaine exposure produced distinct endocannabinoid and glutamate system changes in the cerebellum, implicating it in addiction processes.
MS patients who used cannabis showed worse cognitive performance and more diffuse brain activation on fMRI, suggesting cannabis disrupts compensatory brain mechanisms already strained by MS.
Analysis of 2,142 drug evaluations found field sobriety tests detected impairment across all drug categories including cannabis, with different patterns for each drug class.
Review describes how GW Pharmaceuticals manages cannabis variability in genetics, growing, harvesting, and processing to produce Sativex, the first UK-approved cannabis medicine.