Mixing tobacco with cannabis is linked to nicotine dependence in young adults ↗
Nearly half of young adult cannabis users mixed tobacco with cannabis, and more frequent mixing was associated with greater nicotine dependence.
Research library — page 62
Browse more cannabis research, findings, methods, and limitations.
Self-reported driving high was less common in states with legal cannabis ↗
National survey found cannabis users in legal states were 59-61% less likely to report driving within 3 hours of getting high compared to users in non-legal states.
Could CBD help treat schizophrenia symptoms? ↗
Narrative review found emerging evidence that CBD may address positive, negative, and cognitive symptoms of schizophrenia with fewer side effects than standard antipsychotics.
Could cannabis reduce opioid use in gynecology and obstetrics? ↗
Review found cannabis may reduce opioid use for gynecological pain but noted unclear risks during pregnancy due to lack of controlled trials.
Cannabis extract triggered cancer cell death in 3D pancreatic tumor models ↗
A CBD-rich cannabis extract killed human pancreatic cancer cells in 3D models through apoptosis pathways that the standard drug gemcitabine alone did not activate.
Cannabis-based medicines improved quality of life for autism patients in UK registry ↗
UK registry data showed 74 ASD patients had significant improvements in quality of life, sleep, and anxiety after starting cannabis-based medicines.
Chronic cannabis use may impair the brain's error-correction system through the cerebellum ↗
Review and computational model suggest chronic cannabis use impairs the cerebellum's ability to process sensory errors, explaining observed motor learning deficits.
Acidic cannabinoids, especially CBGA, blocked a key inflammatory pathway in immune cells ↗
Minor acidic cannabinoids, especially CBGA, potently blocked a key calcium-driven inflammatory pathway in immune cells, while CBD and THC did not.
Combining alcohol and cannabis increased driving impairment beyond either drug alone ↗
A controlled trial found combining alcohol and cannabis increased driving impairment beyond either substance alone, and users were unaware of the added impairment.
How young adults' cannabis use patterns changed after California legalized recreational use ↗
Longitudinal study tracked how young adults' cannabis use and medical patient status shifted after California legalized recreational use.
Motivational interviewing reduced alcohol use in Hispanic and non-Hispanic adolescents ↗
RCT found motivational interviewing reduced alcohol use equally well in Hispanic and non-Hispanic adolescents, with indirect effects on cannabis use through motivation.
Licensed California cannabis shops verified age 100% of the time in compliance checks ↗
All 50 licensed California cannabis outlets checked required age verification, suggesting effective compliance with minimum age laws.
Swedish Workplace Drug Tests Over 25 Years: Positive Results Quadrupled, With Cannabis Driving the Recent Surge ↗
25 years of Swedish workplace drug testing showed positive results quadrupling from 1.3% to 5.6%, with cannabis becoming the most detected substance after 2007.
Broad-spectrum cannabis oil reversed fibromyalgia-like symptoms in mice ↗
Low-THC broad-spectrum cannabis oil reversed pain, thermal sensitivity, and depression in a mouse fibromyalgia model at doses as low as 0.1 mg/kg.
Housing First program reduced alcohol and cannabis use among homeless individuals ↗
A randomized trial found Housing First reduced alcohol and cannabis use among homeless individuals at 21 months, with additional mental health benefits for those with severe mental illness.
A cannabinoid receptor agonist broadly suppressed inflammatory gene activity in human brain cells ↗
A synthetic cannabinoid broadly suppressed inflammatory gene expression in human astrocytes through CB1-independent mechanisms involving neuroprotective transcription factors.
Cochrane review: nabiximols probably reduces MS spasticity, but pain evidence is uncertain ↗
Cochrane review of 25 trials found nabiximols probably reduces MS spasticity (moderate certainty) but uncertain evidence for chronic pain, with modestly increased side effects.
The DSM-5 cannabis use disorder diagnosis holds up well, especially for severe cases ↗
Study validated the DSM-5 cannabis use disorder diagnosis and severity levels, with severe CUD showing the strongest associations with psychiatric and social impairment.
Veterans who co-use tobacco and cannabis have worse mental health symptoms ↗
Survey of 1,230 veterans found those who co-used tobacco and cannabis had significantly higher stress, PTSD, depression, and anxiety than single-substance users.
Early reports on medicinal cannabis for childhood autism look positive but evidence is very limited ↗
Scoping review found 61-93% of children with autism showed improvement with medicinal cannabis in small studies, with up to 80% reducing other medications.
How cannabis and cannabinoids affect reproductive hormones and fertility ↗
Review found THC disrupts reproductive hormones, egg development, and sperm function through the hypothalamic-pituitary-gonadal axis, though mostly from preclinical evidence.
Arthritis patients reported less pain and reduced medication use with CBD ↗
Survey of 428 arthritis patients found CBD was associated with 44% average pain reduction, and 60% reduced or stopped other medications including opioids.
CBD disrupted fear memory reconsolidation in female rats through hippocampal CB1 receptors ↗
CBD disrupted fear memory reconsolidation in female rats through hippocampal CB1 receptors, reducing fear behavior for over a week without reinstatement.
Cannabis use more than doubled the risk of suicide attempt in youth ages 11-21 ↗
Meta-analysis of 20 studies found cannabis use was associated with 2.3x risk of suicide attempt, 2.0x suicidal ideation, and 1.7x suicide planning among youth ages 11-21.
CBD combined with ginseng compound in nanoparticles achieved 82% tumor inhibition in breast cancer mice ↗
CBD combined with a ginseng compound in nanoparticles achieved 82% tumor inhibition in breast cancer mice with good tolerability.
Cannabis exposure significantly altered DNA methylation in human ovarian follicle cells ↗
First study of its kind found cannabis exposure altered DNA methylation at 3,679 sites in human ovarian follicle cells, some in a dose-dependent manner.
Young adults with ADHD had significantly higher rates of cannabis and other substance use disorders ↗
Nationally representative Canadian data showed young adults with ADHD had 46% higher odds of cannabis use disorder and 69% higher odds of any substance use disorder.
Regular cannabis users showed better facial emotion recognition, including those with schizophrenia ↗
Large study of 6,229 people found lifetime cannabis use was linked to better facial emotion recognition across schizophrenia patients, siblings, and healthy controls.
Cannabinoid-related psychiatric hospitalizations increased nearly 5-fold in Germany over 18 years ↗
German hospital data showed a 4.8-fold increase in cannabinoid-related psychiatric admissions from 2000-2018, while alcohol and schizophrenia admissions remained stable or declined.
A neutral CB1 blocker reduced cocaine-seeking behavior in animals without the side effects of rimonabant ↗
A neutral CB1 antagonist reduced cocaine-seeking behavior and relapse in rodents through dopamine pathways without the side effects seen with rimonabant.
CB2 receptors may play a key role in alcohol addiction ↗
Converging evidence from animal models and human studies suggests CB2 cannabinoid receptors play an important role in alcohol addiction biology.
Prenatal exposure to multiple substances, including cannabis, increased childhood ADHD risk ↗
Birth cohort study found prenatal opioid exposure doubled ADHD risk, with cannabis and alcohol interactions increasing risk further.
Blocking endocannabinoid signaling combined with stress hormones made fear memories stronger and more generalized ↗
Combining stress hormones with a CB1 blocker turned normal fear memories into intense, generalized ones resembling traumatic memories in rats.
Cognitive behavioral therapy for insomnia improved sleep, mood, and reduced cannabis use ↗
Pilot study showed CBT for insomnia resolved sleep problems in cannabis users, with 80% reducing cannabis use at 3 months and sustained improvements in mood.
Cannabis use during the pandemic was associated with higher suicidal thinking among Canadian adults ↗
Canadian survey during COVID-19 found increased cannabis use was associated with nearly twice the odds of suicidal ideation, alongside social isolation and depression.
Schizophrenia with heavy cannabis use showed different brain structure than cannabis-induced psychosis ↗
Brain imaging showed schizophrenia patients with cannabis use had thinner cortex than cannabis-induced psychosis patients, supporting distinct pathophysiology.
Boosting endocannabinoid levels disrupted habit formation in mice ↗
Boosting either major endocannabinoid (anandamide or 2-AG) disrupted habitual behavior formation in mice, suggesting potential for preventing compulsive drug seeking.
Cannabis flower with balanced THC and CBD produced less anxiety and paranoia than THC-only strains ↗
Trial found cannabis flower with balanced THC:CBD produced similar positive effects but significantly less anxiety and paranoia than THC-dominant flower.
A portable brain scanner detected THC impairment more accurately than field sobriety tests ↗
Portable brain imaging with machine learning detected THC impairment with 76% accuracy and only 10% false positives, outperforming field sobriety tests.
Cannabinoids showed limited benefit for chronic primary pain in short-term studies ↗
Meta-analysis of 8 small trials found cannabinoids showed limited short-term pain benefit, but treatment beyond 4 weeks significantly reduced chronic primary pain.
Cannabis use did not predict negative beliefs about antipsychotic medications ↗
Among 265 first-treatment psychosis patients, cannabis use was not linked to negative beliefs about antipsychotic medications despite predicting poor adherence.
Getting a medical cannabis license did not reduce opioid prescription use in Rhode Island ↗
Population-based study found obtaining a medical cannabis license in Rhode Island was not associated with any change in opioid prescription filling patterns.
Low risk perception and high accessibility predicted cannabis use among Spanish teens ↗
Large Spanish survey found low cannabis risk perception and high accessibility mediated the path from demographics to cannabis use among 35,369 adolescents.
Most people are poorly informed about cannabis health risks, especially psychosis ↗
Survey of 72,459 people found most knew about driving and pregnancy risks of cannabis, but only 23-37% knew about psychosis risk, with frequent users knowing least.
Canada's mandatory cannabis warning labels tripled health risk recall after legalization ↗
Canada's mandatory cannabis warning labels tripled health risk recall post-legalization, significantly outpacing U.S. states with less comprehensive requirements.
CB2 receptors play a complex, age- and sex-dependent role in motor tics ↗
CB2 receptors suppress motor tics in adult mice but may generate them in juveniles, with sex differences potentially relevant to Tourette syndrome prevalence.
Clinical guideline recommends avoiding cannabis during pregnancy and breastfeeding ↗
Canadian clinical guideline recommends avoiding cannabis during pregnancy and breastfeeding, with harm reduction strategies when abstinence is not feasible.
THC and CBD each affected brain responses to unexpected sounds differently based on cannabis use history ↗
Controlled trial showed THC and CBD each altered brain responses to unexpected sounds, with CBD modifying THC's effects differently in frequent vs less-frequent users.
Discouraging breastfeeding for cannabis-using mothers may cause more harm than good ↗
Ethics analysis found discouraging breastfeeding in cannabis-using mothers may cause net harm, compromise autonomy, and worsen racial health disparities.
Most published case reports claiming cannabis fights cancer provide insufficient evidence ↗
Review of 77 published case reports found only 14% provided strong evidence for cannabis anticancer effects, with 81% rated weak and no supporting clinical trial data.