A 23-year-old experienced recurring catatonia episodes triggered by cannabis use ↗
A 23-year-old with substance use history developed recurrent catatonic episodes after cannabis use, requiring ongoing lorazepam to prevent relapse.
Research library — page 88
Browse more cannabis research, findings, methods, and limitations.
How You Use Cannabis Changes What It Does to Your Heart and Lungs: A Systematic Review by Route ↗
Systematic review finds smoking cannabis carries the most cardiovascular and respiratory risks, vaping may reduce respiratory harm, and edibles/dabbing are poorly studied.
Cannabis-based medicine for tic disorders did not impair driving and may have actually improved it ↗
Randomized trial found nabiximols for tic disorders did not impair driving and improved it in 42% of patients who were initially unfit to drive.
Practical guide finds growing evidence for cannabinoids in autism, Tourette syndrome, anxiety, and PTSD ↗
Clinical review finds growing evidence for cannabinoids in autism, Tourette syndrome, anxiety, and PTSD, with practical dosing: start 1-2.5 mg THC/day, target 10-20 mg.
Cannabis use disorder was not linked to worse outcomes after complex cancer surgery ↗
Among 15,014 matched cancer surgery patients, cannabis use disorder was not independently associated with worse overall outcomes, though kidney injury was slightly elevated.
UK medical cannabis patients with MS reported improved quality of life across multiple domains over six months ↗
UK registry data from 141 MS patients found prescribed cannabis products improved quality of life across cognitive, physical, emotional, and social domains over six months.
People with HIV had altered endocannabinoid levels, but cannabis use frequency did not change immune markers ↗
People with HIV showed higher inflammation and lower endocannabinoid levels, but cannabis use frequency did not alter these immune measures.
Cannabis extracts blocked multiple steps of atherosclerosis development in lab cells ↗
Three cannabis extracts blocked LDL oxidation, foam cell formation, and inflammation through non-traditional receptors, targeting multiple steps of plaque development.
People who visited the ER for cannabis had nearly four times the risk of developing an anxiety disorder ↗
Among 12 million Ontarians, cannabis-related ER visits were linked to nearly 4x higher risk of anxiety disorder within three years, with young males at highest risk.
Cannabis-involved self-harm ER visits nearly doubled over 12 years in Ontario, accelerating after medical cannabis liberalization ↗
Cannabis-involved self-harm ER visits increased 90% over 12 years in Ontario after medical liberalization, while alcohol-involved self-harm declined.
Real-World Cannabis Drug Interactions: A Systematic Review Found 31 Documented Cases with Serious Medications ↗
Systematic review found 31 documented cases of serious drug interactions between cannabis and narrow-therapeutic-index medications — likely a vast undercount of the true burden.
What Half a Million Cannabis Products Look Like on a Major Online Marketplace ↗
Analysis of 500K+ cannabis product listings from Weedmaps found THC dominates, 42% feature flavor marketing, and multisystem delivery methods are most common.
Testing a Web Tool to Help Teen Drivers Avoid Cannabis- and Alcohol-Impaired Driving ↗
A web-based tool for teen drivers addressing cannabis and alcohol impaired driving showed strong acceptability in early testing, with nearly all participants finding it helpful.
How Cannabis May Change the Adolescent Brain at the Cellular Level ↗
A translational study connecting mouse neuroscience with human brain imaging identified specific genes and cell types that may explain cannabis-related cortical thinning in adolescents.
Mouse Model of Prenatal THC Exposure Shows Anxiety, Depression, and Increased Alcohol Preference in Offspring ↗
A mouse model of high-dose prenatal THC exposure found offspring developed anxiety, depression, cognitive problems, and increased alcohol preference, with sex-dependent effects.
Cannabis-Related Diagnoses Among Pregnant Women Rose 24% After Canada Legalized Non-Medical Use ↗
Diagnosed cannabis-related disorders among pregnant women in Quebec rose 24% after Canada legalized non-medical cannabis.
ER Visits for Cannabis Intoxication Jumped After Michigan Legalized Recreational Use ↗
Cannabis-related ER visits in Michigan rose 47-70% immediately after recreational legalization across 8 hospitals.
Cannabis Legalization Showed No Clear Effect on Opioid Prescriptions or Overdose Deaths ↗
Rigorous 15-year analysis found cannabis legalization had no significant effect on opioid prescriptions or deaths overall.
Why We Urgently Need Better Treatments for People Who Use Both Tobacco and Cannabis ↗
Only 9 studies address tobacco-cannabis co-use treatment. Combined therapy showed promise with no compensatory use.
68% of Psychiatric Patients with Psychotic Disorders in Greenland Had Harmful Cannabis Use ↗
Study of 104 psychotic disorder patients in Greenland found 68% had harmful cannabis use and 80%+ smoked daily.
Review of Cannabinoids for Multiple Sclerosis and the Emerging Field of Nano-Cannabinoid Medicine ↗
Review examines cannabinoids' disease-modification potential in MS and nano-cannabinoid drug delivery.
Prenatal Cannabis Use Did Not Predict Autism-Related Behaviors in Black Children ↗
In 172 Black mother-child pairs, prenatal cannabis did not predict autism behaviors. Stress was the risk factor.
Largest Multi-Cohort Study Finds No Link Between Prenatal Cannabis and Autism After Controlling for Tobacco ↗
Largest study (11,570 children, 34 cohorts) found no prenatal cannabis-autism link after controlling for tobacco.
Peer Cannabis Use Was the Strongest Predictor of Teen Cannabis Use in Ireland ↗
Irish survey of 4,400+ teens found peer cannabis use was the strongest risk factor (10x odds).
CBD Did Not Block THC's Effect on Attentional Bias Toward Cannabis Cues ↗
Crossover trial: THC increased attentional bias toward cannabis cues; CBD at three doses did not help.
Comprehensive Review of CBD's Potential for Brain Disorders ↗
Review of 170 articles maps CBD's neuroprotective mechanisms across brain disorders.
A Case of Cannabinoid Hyperemesis Syndrome Initially Misdiagnosed ↗
Case of CHS misdiagnosed in a chronic cannabis user, resolving after cessation.
CBD Shifted Immune Responses in Blood Cells from Psoriasis Patients ↗
Lab experiments showed CBD shifted immune responses in psoriasis patients' blood cells from inflammatory to anti-inflammatory across multiple immune cell types.
Switzerland's Legal Tension Between Medical Cannabis and Zero-Tolerance Driving Laws ↗
Switzerland's 2022 medical cannabis deregulation conflicts with zero-tolerance THC driving laws, creating legal uncertainty for prescribed patients.
Cannabis Use Made It Harder for LGBTQ+ Smokers to Quit Cigarettes ↗
LGBTQ+ dual users who also used cannabis had smaller reductions in cigarette smoking during quit attempts, especially on cannabis-use days.
How the Endocannabinoid System Affects Liver Disease ↗
Review finds the endocannabinoid system has opposing effects in liver disease: CB1 promotes fibrosis while CB2 inhibits it, suggesting targeted cannabinoid therapies could help.
More Permissive Cannabis Laws Linked to Fewer Traffic Deaths, But Medicalization Linked to More ↗
Analysis of US state cannabis policies over 27 years found permissive laws linked to fewer traffic deaths, while pharmaceutical-style regulations were linked to more.
Cannabis Use Disorder Showed No Significant Link to Atrial Fibrillation in Young Men After Accounting for Confounders ↗
Propensity-matched analysis of 216K+ young men found cannabis use disorder was not significantly linked to atrial fibrillation after excluding tobacco users.
Nepal's Debate Over Cannabis Legalization: Cultural History Meets Modern Policy ↗
Despite deep cultural roots, Nepal's 1976 cannabis prohibition persists even as legalization advocates grow. The country looks to global experiences for guidance.
Prenatal Cannabinoid Exposure Caused Sex-Specific Changes in Breathing, Heart Function, and Anxiety in Adult Rats ↗
Adult rats exposed to a synthetic cannabinoid before birth showed sex-specific changes in breathing control, cardiovascular function, and anxiety behavior.
Preschool Self-Control Problems Linked to Teen E-Cigarette Use Through Harsher Parenting ↗
Preschool executive control problems predicted harsher parenting in adolescence, which in turn predicted higher teen e-cigarette use, though not cannabis or alcohol use.
CBD's Therapeutic Potential for Autism Spectrum Disorder ↗
Review finds CBD shows promise for autism through endocannabinoid system interaction, gut-brain modulation, and a favorable safety profile, though evidence is still preliminary.
Most Online Cannabis Health Information Accessed by Thai Breast Cancer Survivors Is Poor Quality ↗
Study found most online cannabis health content accessed by Thai breast cancer survivors was poor quality, with alternative medicine providers producing the most misleading information.
Vaporized THC During Pregnancy Impaired Attention in Rat Offspring, Especially at Low Doses ↗
First study using vaporized prenatal THC found decreased attention in rat offspring, with low doses producing more pronounced effects than high doses.
Cannabis Use Among Forensic Mental Health Patients Rose After Canadian Legalization, With Clinical Consequences ↗
Cannabis use among 187 forensic psychiatric patients rose after Canadian legalization, with over half showing mental health decline after use, though violence rates did not increase.
Prescription CBD Helped About 1 in 4 Adults with Drug-Resistant Epilepsy, Regardless of Epilepsy Type ↗
Pharmaceutical CBD helped about 25-29% of adults with various drug-resistant epilepsies in French epilepsy centers, with no difference in response between epilepsy types.
Prenatal Tobacco-Cannabis Co-Exposure Affected Children's Emotion Regulation Through Ongoing Maternal Risk Factors ↗
Prenatal tobacco-cannabis co-exposure affected children's emotional regulation primarily through ongoing maternal stress and substance use, not direct prenatal effects. Sensitive parenting buffered risks.
Prenatal Cannabis Exposure Altered Dopamine Brain Circuits in Mouse Offspring But Did Not Increase Cocaine-Seeking ↗
Prenatal cannabis oil exposure altered VTA dopamine neurons in male mice (disinhibited firing) but did not increase cocaine-seeking in either sex.
Childhood Neglect Predicted Teen Cannabis Use Through Impulsive Decision-Making ↗
Neglected adolescents were more likely to develop impulsive decision-making that led to increased cannabis use over time, identifying a specific prevention target.
Cannabis Use Rose While Tobacco Fell Across All Drinking Levels in the US, 2010-2019 ↗
US data from 2010-2019 showed cannabis use rising across all drinking levels while tobacco fell, with the fastest cannabis increase among non-drinkers.
Mindfulness Skills Were Linked to Less Cannabis and Alcohol Use in Argentine College Students ↗
Higher mindfulness skills in Argentine college students were linked to less cannabis use through reduced emotional distress and lower coping-based use motives.
Three Synthetic Cannabinoids Caused Lasting Anxiety, Motor Problems, and Memory Impairment in Mice ↗
Three synthetic cannabinoids caused prolonged anxiety, motor disruption, and endocannabinoid system dysregulation in mice, with one also impairing memory.
Even Low Doses of Synthetic Cannabinoid JWH-018 Caused Lasting Heart Damage and Multi-Organ Injury in Rats ↗
Low-dose JWH-018 for two weeks caused persistent cardiovascular effects, cardiac lesions, mitochondrial dysfunction, and multi-organ damage in rats that worsened after discontinuation.
Heavy Cannabis Use Combined With Disrupted Cortisol Patterns Tripled the Risk of Suicidal Thoughts ↗
Five-year study found heavy cannabis users with disrupted cortisol stress responses had 3.2x higher odds of suicidal thoughts and behaviors.
Chronic Cannabis Use in Teens Was Linked to Lower B Cell Levels, Hinting at Immune Effects ↗
Small exploratory study found chronic cannabis-using teens had lower B cell proportions, suggesting possible immune effects that need confirmation in larger studies.