Sativex Did Not Impair Cognitive Function in MS Patients Over 6 Months ↗
40 cannabis-naive MS patients showed no significant cognitive or behavioral decline after 6 months of Sativex treatment for spasticity.
Research library — page 26
Browse more cannabis research, findings, methods, and limitations.
School Drug Prevention Program Reduced Marijuana Use Among Brazilian Teens Aged 13-15 ↗
Brazilian school drug prevention program showed 85.7% of teen marijuana users in the intervention group stopped using, compared to 28.6% in controls.
Adolescent THC Exposure Made Adult Rats Seek More Cannabinoids by Changing Their Reward System ↗
Adolescent THC exposure in rats enhanced adult cannabinoid self-administration and blunted dopamine reward signaling, providing a biological mechanism for increased addiction vulnerability after early cannabis use.
A New Type of CB1 Blocker Reduced Both Nicotine and Cannabis Seeking in Monkeys ↗
A CB1 neutral antagonist reduced both nicotine and cannabis seeking in monkeys without affecting food motivation, offering a potentially safer alternative to the withdrawn drug rimonabant.
A Drug Designed to Boost Natural Endocannabinoids Was Itself Addictive in Monkeys ↗
An endocannabinoid-boosting compound being studied as a potential anti-smoking treatment was itself self-administered by monkeys, raising concerns about abuse potential of this drug class.
Social Rejection in Adolescent Rats Changed Pain Sensitivity Through the Endocannabinoid System ↗
Adolescent rats experiencing social rejection from unresponsive partners developed altered pain sensitivity through endocannabinoid CB1 signaling, linking social and physical pain processing.
Medical Implications of Cannabinoids: What the Evidence Supports and Where Caution Is Needed ↗
Comprehensive review finds strong evidence for cannabinoids in chronic pain and MS symptoms, emphasizes careful patient selection and informed consent about cognitive, behavioral, and health risks.
Cannabis Use Predicted Suicidal Thoughts in Men, While Suicidal Thoughts Predicted Cannabis Use in Women ↗
Large longitudinal study reveals sex-specific patterns: daily cannabis use predicted 4-fold increased suicidal ideation risk in men, while suicidal ideation predicted cannabis initiation in women.
Hair Drug Tests Agreed Well With Self-Reports for Cannabis But Poorly for Cocaine ↗
In 1,285 ED patients, hair analysis and self-reported drug use agreed well for cannabis and street opioids but poorly for cocaine, with people most accurately reporting their primary drug of choice.
Pre-College Marijuana Use Predicted Starting Hookah Smoking in the First Month of College ↗
Longitudinal study of 936 college freshmen finds pre-college marijuana use predicted hookah initiation in the first month of college, alongside alcohol as the only other predictor.
Cannabis Users Consistently Had Equal or Lower Diabetes Risk Despite Known Metabolic Effects ↗
Review finds cannabis users consistently have equal or lower diabetes and obesity rates despite cannabis activating the same system that controls fat storage and appetite.
THC Suppressed Immune Inflammation by Reprogramming Immune Cells Through MicroRNA ↗
THC suppressed immune inflammation in mice by correcting dysregulated microRNA molecules that control inflammatory T cell development, revealing a precise molecular mechanism.
Prenatal Marijuana Exposure Was Linked to Altered Brain Activity in Young Adults 18-22 Years Later ↗
Young adults prenatally exposed to marijuana showed altered brain activation (increased left posterior activity) during executive function tasks despite normal performance, suggesting neural compensation 18-22 years after exposure.
Cannabis and Cocaine Had Opposite Acute Effects on Impulse Control and Brain Activity ↗
Controlled crossover study finds cocaine enhanced and cannabis impaired impulse control with mirror-image effects on brain electrical activity, both acting on evaluative rather than detection stages of inhibition.
Teens Reducing Marijuana Also Drank Less Alcohol When Taking NAC ↗
In a teen marijuana cessation trial, NAC-treated adolescents who reduced marijuana use also reduced alcohol use, with no compensatory increase in drinking.
Generalized Anxiety in Teens Was the Strongest Predictor of Starting Cannabis Use ↗
Among 2,508 Chilean teens, generalized anxiety was the only mental health symptom that independently predicted both starting cannabis use and using more frequently over 18 months.
Cannabinoids Impaired Learning But Actually Helped Memory Consolidation in the Cerebellum ↗
Cannabinoids in the cerebellum impaired new learning but enhanced memory consolidation in a specific 1-3 hour window after training, revealing a dual role in memory processing.
The Brain's Anti-Nausea System Works Through a Specific Endocannabinoid in a Specific Brain Region ↗
Nausea selectively increased the endocannabinoid 2-AG in the brain's visceral insular cortex, and boosting 2-AG there reduced nausea by dampening neural activity through CB1 receptors.
Largest Genetic Study of Cannabis Use Found Four Genes and a Strong Genetic Overlap With Tobacco ↗
Largest cannabis GWAS (32,330 people) identified four genes and found genetics explain 13-20% of cannabis use variation, with 83% genetic overlap with cigarette smoking.
A Practical Guide for Physicians on Cannabinoids in Medical Practice ↗
Clinical review outlines cannabinoid evidence for physicians: strongest for chemo nausea, HIV appetite, pain, and MS spasticity, with practical guidance for patient conversations.
Cannabis May Change How Genes Are Expressed, and These Changes Could Pass to the Next Generation ↗
Review finds cannabis can alter epigenetic marks controlling gene expression in brain and body, with emerging evidence suggesting some changes may pass to offspring.
Cannabinoids for Chemotherapy Nausea: Effective but Less Tolerated Than Modern Anti-Nausea Drugs ↗
Systematic review of reviews finds moderate evidence cannabinoids reduce chemo nausea but are less tolerated than modern antiemetics, positioning them as third-line therapy for treatment-resistant cases.
Cannabis Use Was Strongly Associated With Having Tried E-Cigarettes Among French College Students ↗
Among 1,134 French college students, cannabis use was strongly associated with e-cigarette experimentation (2.44x odds), and nearly half of e-cigarette experimenters had never smoked cigarettes.
Surveying Patients at Marijuana Dispensaries Produces Representative Data With Minimal Bias ↗
UCLA study validates that surveying medical marijuana patients at dispensaries produces representative data with minimal selection or respondent bias.
Sativex Markedly Reduced Severe Tics in a Treatment-Resistant Tourette Syndrome Case ↗
A treatment-resistant Tourette syndrome patient showed marked improvement in motor and vocal tics after starting Sativex, confirmed by blinded objective video assessment.
Sativex at High Fixed Doses Reduced Cannabis Withdrawal Symptoms in Dependent Users ↗
Proof-of-concept trial shows high fixed doses of Sativex significantly reduced cannabis withdrawal symptoms but not craving, with self-titrated doses proving insufficient.
Boosting the Endocannabinoid 2-AG Enhanced Cue-Triggered Nicotine Seeking in Mice ↗
Boosting the endocannabinoid 2-AG did not affect nicotine self-administration but significantly enhanced cue-triggered nicotine seeking in mice, implicating 2-AG in tobacco relapse.
THC:CBD Spray Improved MS Spasticity in Real-World Italian Clinics at Lower Doses Than Clinical Trials ↗
Large Italian observational study finds MS patients achieve spasticity improvements with THC:CBD spray at one-third the clinical trial dose and one-third the adverse event rate in real-world practice.
Cannabis Use Was Linked to Lower Motivation to Quit Tobacco Among Disadvantaged Smokers ↗
Among 369 disadvantaged Australian smokers, 19% used cannabis concurrently (100% simultaneously), and cannabis use was associated with lower motivation but not lower intention to quit tobacco.
89% of Children With Treatment-Resistant Epilepsy Had Fewer Seizures With CBD Oil ↗
Multicenter Israeli study found 89% of 74 children with severe, treatment-resistant epilepsy (failed 7+ drugs) had seizure reduction with CBD-enriched cannabis oil, with 18% achieving 75-100% reduction.
E-Cigarette Use Predicted Starting Marijuana Among Hispanic Young Adults Who Had Not Previously Used It ↗
Longitudinal study finds e-cigarette use by Hispanic young adults predicted nearly 2x higher odds of starting marijuana and 3x higher odds of starting cigarettes one year later.
Experiencing More Discrimination Over Time Was Linked to Higher Marijuana Use Among Hispanic Youth ↗
Study of 2,722 Hispanic youth finds that increasing or persistently high discrimination trajectories from age 14-23 predicted higher marijuana, alcohol, and hard drug use.
Chronic Cannabinoid Receptor Activation in Human Pancreatic Islets Did Not Impair Function ↗
Human pancreatic islets exposed to cannabinoid receptor agonists for up to 5 days showed gene expression changes but no impairment of insulin secretion or cell survival.
Brain Response to Cannabis Cues Predicted Who Would Have Cannabis Problems 3 Years Later ↗
Brain response to cannabis cues in the left striatum predicted cannabis problem severity 3 years later, independent of how much cannabis was used, suggesting a neural biomarker for addiction risk.
ADHD Was a Risk Factor for Starting New Substances, Independent of Conduct Problems ↗
Study of 5,103 Swiss men finds ADHD predicted initiating new substances (especially amphetamines) over 15 months, independent of conduct disorder, without escalating existing substance use.
Cochrane Review Found No Convincing Evidence That Cannabinoids Help Fibromyalgia ↗
Cochrane review found only 2 small studies (72 patients) of cannabinoids for fibromyalgia, all with very low quality evidence, concluding no convincing support for their use.
Psychotherapy Remains the Best Treatment for Cannabis Dependence, With No Approved Medications ↗
Review finds CBT-based psychotherapy has moderate-to-large effects on cannabis dependence (evidence level Ia), no pharmacotherapy is approved, and serotonergic antidepressants may worsen outcomes.
Pediatric Marijuana Exposures in Colorado Increased Significantly After Recreational Legalization ↗
Colorado pediatric marijuana exposures nearly doubled at a children's hospital and increased 5-fold at the poison center after recreational legalization, with edibles responsible for ~50% of cases.
Just One Minute of Marijuana Secondhand Smoke Impaired Blood Vessel Function for 90 Minutes ↗
Just one minute of marijuana secondhand smoke impaired blood vessel function for 90+ minutes, longer than tobacco smoke, and the effect was caused by combustion products, not cannabinoids.
Marijuana Smokers Had Higher Levels of Toxic Combustion Chemicals in Their Urine ↗
National survey data shows exclusive marijuana smokers had significantly elevated urinary levels of carcinogenic combustion by-products (PAHs, VOC metabolites) compared to non-users.
Boosting the Endocannabinoid Anandamide Completely Reversed Social Impairment in Two Autism Mouse Models ↗
Boosting anandamide levels completely reversed social impairment in two autism mouse models (BTBR and Fragile X) through CB1 receptors, identifying FAAH as a novel therapeutic target for ASD.
Chronic THC Did Not Worsen SIV Infection in Monkeys and May Have Reduced Mortality ↗
Long-term THC administration in SIV-infected monkeys did not enhance viral replication, reduced IgE+ B cells, and showed a non-significant trend toward lower mortality compared to placebo.
Comprehensive Brain Imaging Review: How Cannabis Changes Brain Structure and Function ↗
Review of 103 brain imaging studies shows regular cannabis use alters brain structure (hippocampus, amygdala), cognitive function (with compensatory recruitment), dopamine systems, and CB1 receptors.
Heavy Cannabis Users Showed Reduced Brain Activity When Evaluating Emotional Content ↗
fMRI study finds heavy cannabis users show reduced medial prefrontal cortex activity during conscious emotional evaluation of both positive and negative content.
Marijuana Use Was Not Associated With Reduced Ovarian Reserve, Unlike Tobacco ↗
Among 913 premenopausal women, heavy tobacco smoking reduced ovarian reserve markers by 56%, but marijuana use showed no association with antimullerian hormone levels.
The Appetite-Reducing Effect of Combining Leptin With a CB1 Blocker Required Serotonin Receptors ↗
Serotonin 5-HT1B and 5-HT2C receptors are required for the appetite-suppressing effect of combining leptin with a CB1 blocker, revealing a three-way neuroendocrine interaction in feeding behavior.
An Endocannabinoid-Boosting Drug Enhanced Morphine's Pain Relief Without the Side Effects ↗
MAGL inhibitor MJN110 synergized with morphine for neuropathic pain relief without constipation, cannabis-like effects, or tolerance development after 6 days of dosing.
20% of Synthetic Cannabinoid Users Among Police Detainees Reduced or Stopped Natural Cannabis Use ↗
Survey of 848 NZ police detainees found 20% of synthetic cannabinoid users reduced or stopped natural cannabis use, suggesting modest substitution, though SC users had higher baseline cannabis consumption overall.
58% of Frequent Synthetic Cannabinoid Users Were Classified as Dependent ↗
Survey of 105 frequent legal high users in Auckland found 58% of synthetic cannabinoid users met dependence criteria, with common reports of insomnia (29%), nausea (25%), and anxiety (21%).
Marijuana Legalization: What Doctors and Public Health Need to Know ↗
Annual Review of Medicine assessment finds limited medical cannabis evidence (4 conditions), notes pre-legalization high use in legal states, and identifies key public health concerns for physicians.