CB1 Activation Reduced Fear Memories in Stressed Female Rats But May Hinder Extinction ↗
Study in female rats finds CB1 activation reduces acute fear but may impair fear extinction, with important implications for cannabis use in PTSD treatment.
Research library — page 130
Browse more cannabis research, findings, methods, and limitations.
People of Color Are Severely Underrepresented in Cannabis Use Disorder Treatment Research ↗
Systematic review finds White participants are represented at 49 times their share of cannabis use disorder cases in treatment trials, with zero studies culturally adapted for people of color.
Chile's Cannabis Use Plummeted 90% While Cocaine Surged, Wastewater Data Shows ↗
Two years of wastewater surveillance in Chile found cannabis use dropped 90% while cocaine surged tenfold, revealing a dramatic shift in the regional drug landscape.
How Cannabinoids May Fight the Deadliest Brain Cancer Through Autophagy ↗
Review details how cannabinoids activate autophagy-mediated cell death in glioblastoma, with promising preclinical evidence and early clinical safety data.
People Who Fear Anxiety and Believe Cannabis Helps Are Most Likely to Use It to Cope ↗
Study finds coping-oriented cannabis use is driven by the combination of anxiety sensitivity and positive cannabis expectations, explaining previous inconsistent findings.
Cannabis Users Had Fewer Heart Rhythm Problems Than Cocaine Users in Large Study ↗
Matched study of ~250,000 patients per group found cocaine users had significantly more arrhythmias, heart attacks, strokes, and deaths than cannabis users.
Cannabis, Cocaine, and Amphetamines All Linked to Higher Stroke Risk in Major Analysis ↗
Meta-analysis of 100+ million participants plus genetic analysis confirms cannabis use disorder is causally linked to stroke, particularly large artery stroke.
Veterans With PTSD Who Quit Cannabis Saw Major Symptom Improvement ↗
Pilot study found veterans with PTSD who achieved 12 weeks of cannabis abstinence saw 71% symptom reduction vs. 37% in those who continued using.
Young Parents' Cannabis Use Patterns Vary Dramatically by Demographics and Life Situation ↗
Study of 1,247 young parents finds single mothers use cannabis most frequently for coping, while educated fathers have the most consequences and driving under the influence.
CBD Oil Did Not Improve Psoriasis Severity But Temporarily Relieved Itch and Sleep ↗
RCT finds oral CBD at 60 mg/day did not improve psoriasis severity versus placebo, though temporary benefits in itch and sleep onset were observed.
THC Drug Dronabinol Safely Reduced Agitation in Alzheimer's Patients in Clinical Trial ↗
Multicenter RCT finds dronabinol (THC) safely and effectively reduces Alzheimer's agitation over 3 weeks with a medium effect size and no cognitive decline.
Endocannabinoids Are Stored in Adrenal Stress Hormone Packages and Influence Hormone Production ↗
Study reveals endocannabinoids are stored alongside stress hormones in adrenal glands and directly modulate hormone production, connecting the ECS to the peripheral stress response.
CBD-THC Mixture Helped Brain Immune Cells Clear Alzheimer's Plaques in Mice ↗
CBD:THC (99:1) mixture enhanced microglial clearance of Alzheimer's plaques in mice but also worsened anxiety and depression behaviors, highlighting the therapeutic trade-off.
Cannabis use after Canadian legalization increased mainly among people without mental health problems ↗
A study of nearly 93,000 Canadians over five years found cannabis use after legalization increased mainly among those without mental health problems, with people reporting anxiety, depression, bipolar disorder, PTSD, or schizophrenia showing few changes in use.
Three-quarters of adults with ADHD have tried cannabis, with daily users showing higher rates of anxiety and addiction ↗
A survey of 900 adults with ADHD found 75% had used cannabis, with daily users showing significantly higher rates of cannabis use disorder (62%), anxiety (70%), and worsened inattention compared to non-daily users.
Online cannabis reduction program helped heavy users cut back, with or without therapist introduction ↗
An RCT of 152 Canadian heavy cannabis users found an online self-guided treatment program reduced use frequency and problems, with a brief therapist introduction adding benefit for quantity reduction but not essential for frequency reduction.
Only 1.2% of autistic individuals in Israel's largest health system were prescribed medical cannabis ↗
Among 36,610 autistic individuals in Israel's largest health system, only 1.2% were prescribed medical cannabis, mostly from higher socioeconomic backgrounds with more complex clinical profiles, and most prescriptions did not meet regulatory guidelines.
Cannabis and Linden Tree Extracts Together Showed Powerful Neuroprotective Synergy ↗
Study finds cannabis and linden tree extracts together produce synergistic neuroprotection, fully restoring cell viability and shifting brain immune cells to anti-inflammatory states.
Psychological interventions showed minimal benefit for people with both schizophrenia and substance use disorders ↗
A JAMA Psychiatry meta-analysis of 35 trials (4,136 participants) found current psychological interventions provided no meaningful benefit for reducing substance use in people with schizophrenia, except for a small effect on nicotine, highlighting an urgent need for new treatment approaches.
Cannabigerol showed inconsistent anti-inflammatory effects and was genotoxic at higher doses in brain immune cells ↗
A cell study found CBG was genotoxic at moderate concentrations, highly toxic at high concentrations, and failed to reduce neuroinflammation in microglial cells, challenging claims of CBG as a safe anti-inflammatory cannabinoid.
THC at concentrations found in drivers' blood caused neurotoxicity through oxidative stress in lab cells ↗
THC at concentrations found in the blood of traffic accident drivers caused dose-dependent neurotoxicity in human neuronal cells, including oxidative stress, mitochondrial damage, and early cell death signals.
Meta-analysis: youth cannabis use linked to 28-87% higher odds of depression, anxiety, and suicidal behavior ↗
A meta-analysis of 36 studies found youth cannabis users aged 15-30 had 28% higher adjusted odds of depression, 58% higher odds of anxiety, 65% higher adjusted odds of suicidal ideation, and 80% higher adjusted odds of suicide attempts.
How Cannabis and Tobacco Are Used Together in Spain — and What Withdrawal Looks Like ↗
Study of 94 Spanish cannabis treatment seekers found 88% co-used cannabis with tobacco, 76% had withdrawal symptoms (worse in women), with two distinct user profiles.
THC/CBD therapy nearly halved jaw pain scores and eliminated most functional limitations in TMD patients ↗
A crossover study of 20 TMD patients found 90 days of sublingual THC/CBD (1:1 ratio, 10 mg/day) halved pain scores, improved jaw function, and nearly eliminated pain sensitization, with large effect sizes and minimal placebo response.
Opioid users showed blunted endocannabinoid stress response compared to healthy controls ↗
Healthy controls increased 2-AG endocannabinoid levels after social stress while chronic opioid users showed a blunted response, suggesting a dysfunctional stress buffer that may contribute to opioid vulnerability and relapse.
Eight months after German legalization, no significant increase in cannabis use or stoned driving ↗
A Lancet study comparing Germany and Austria found no significant increases in cannabis use or stoned driving 8 months after German legalization, though 21.5% of driving-under-influence episodes combined cannabis with alcohol or other drugs.
Cannabis Use Didn't Derail Intensive PTSD Treatment for Veterans ↗
Two samples of veterans (N=741 total) showed that cannabis use didn't undermine intensive PTSD treatment — users and non-users improved similarly.
First RCT: vaporized THC+CBD was superior to placebo for acute migraine, with effects lasting 48 hours ↗
The first RCT of cannabis for acute migraine found vaporized THC+CBD significantly superior to placebo for pain relief (67% vs 47%), pain freedom, and symptom freedom at 2 hours, with sustained benefits to 48 hours, while CBD alone was ineffective.
Medical cannabis authorization did not significantly reduce opioid prescribing in a university pain clinic ↗
A university pain clinic study found medical cannabis authorization was associated with a non-significant 14 mg/day decrease in opioid doses, while long-term opioid use status dominated prescribing patterns regardless of cannabis access.
Preoperative cannabis use had no effect on pain or outcomes after cardiac surgery ↗
A prospective study of 73 cardiac surgery patients found no differences in postoperative morphine requirements, pain scores, extubation time, ICU stay, or complications between cannabis users and non-users.
CBD may protect bone by boosting bone-building cells and suppressing bone-breakdown cells, but human trials are still missing ↗
Scoping review of 24 studies finds CBD shows bone-protective effects in about half of preclinical models, enhancing bone-building cells and suppressing bone-breakdown cells through multiple molecular pathways.
Cannabis was the most commonly used substance among first-episode psychosis patients at a South African hospital ↗
Retrospective review of 200 first-episode psychosis patients at a Soweto hospital found 73.6% had substance use, with cannabis most common at 46% and substance-induced psychosis as the top diagnosis.
Four small trials suggest cannabinoids may reduce diabetic nerve pain, but the evidence is too limited for firm conclusions ↗
Systematic review of four small RCTs found three showed significant pain reduction from cannabinoids in diabetic peripheral neuropathy, with THC doses around 16-18 mg/day showing promise.
Testing 11 New Synthetic Cannabinoids: Most Were More Potent Than THC ↗
Rodent testing of 11 DEA-flagged synthetic cannabinoids found most significantly more potent than THC, with indazole and indole classes showing the highest potency.
CBD kept working for over 86% of children with severe epilepsy through two years, with nearly 80% seeing seizures cut in half ↗
Retrospective study of 29 pediatric patients with intractable epilepsy found CBD therapy had 86%+ retention at 2 years, with nearly 80% achieving at least 50% seizure reduction across diverse genetic and non-genetic causes.
College students reported more hits and more negative consequences when using joints or blunts compared to bongs ↗
Ecological momentary assessment of 88 college students found joints and blunts were associated with more hits per session and greater negative consequences compared to bong use.
About 30% of Polish adults support full cannabis legalization, but nearly 40% favor depenalization of personal possession ↗
Nationwide Polish survey of 1,113 adults found limited support for full recreational cannabis legalization (29.6%) but substantially greater acceptance of depenalization (39.6%), with demographic factors strongly shaping attitudes.
Frequent cannabis use among California 11th graders increased after retail legalization, especially where new stores opened ↗
Analysis of 377,205 California 11th graders found frequent cannabis use increased after 2018 retail legalization, with jurisdictions newly allowing storefronts seeing sustained elevated rates while ban jurisdictions saw declines.
British Pharmacology Guidelines for Treating Cannabis and Other Drug Dependencies ↗
British pharmacology consensus guidelines found no approved medications for cannabis or synthetic cannabinoid dependence — a major gap compared to alcohol, opioid, and nicotine treatment.
About a third of endometriosis patients using cannabis reported side effects, but some of those effects might actually be helpful ↗
International survey subset found 32% of endometriosis patients using cannabis reported side effects, but researchers argue some adverse effects may have therapeutic value in this population.
A CBD-rich cannabis extract reduced inflammation and pain in lab animals in a dose-dependent manner ↗
Preclinical study found a chemically characterized CBD-rich cannabis extract reduced inflammatory markers in cells and showed dose-dependent anti-inflammatory and analgesic effects in animal models.
Acidic cannabinoids like THCA and CBDA show unique therapeutic potential but face major hurdles getting to clinical use ↗
Narrative review finds acidic cannabinoids (THCA, CBDA, CBGA, CBCA) have distinct therapeutic properties including neuroprotective and anti-inflammatory effects, but chemical instability and absent human trials limit clinical use.
Mental health and GI relief were the top reasons pregnant women used cannabis, with over 84% citing multiple motivations ↗
Analysis of ~803,000 live births found mental health (83%) and GI symptom relief (77%) were top motivations for prenatal cannabis use, with 84% of users citing multiple reasons.
A simple "how many times per day" question may be better than detailed daily logs for measuring general cannabis exposure ↗
Study of 1,090 cannabis users found a brief quantity-frequency question better predicted long-term THC metabolite levels, while detailed daily logs better predicted acute THC, offering guidance for research measurement.
Medical cannabis program participation was linked to reduced opioid prescriptions over 18 months in a New York study ↗
JAMA Internal Medicine cohort study of 204 chronic pain patients found New York medical cannabis program participation associated with 3.53 fewer daily morphine milliequivalents per month of full dispensation over 18 months.
Low-dose THC boosted dopamine and GABA in the brain's reward center, while high doses decreased dopamine in mice ↗
Mouse study found low-dose THC increased dopamine and GABA in the brain's reward center while high doses decreased dopamine, and a partial CB1 agonist produced no reward-related effects.
E-cigarette and cannabis co-use surged among young adults from 2016 to 2021 while cigarette-cannabis co-use stayed flat or declined ↗
PATH study data from 2016-2021 shows e-cigarette and cannabis co-use rising among young adults while cigarette-cannabis co-use stays flat or declines, reflecting a shifting substance use landscape.
CBD killed kidney cancer cells in lab dishes but lost effectiveness with serum and showed no selectivity for tumor over normal cells ↗
Lab study found CBD killed kidney cancer cells but equally killed normal kidney cells, lost effectiveness in the presence of serum proteins, and required concentrations far beyond clinically achievable levels.
Higher endocannabinoid levels appeared to buffer the link between childhood trauma and inflammation in people with borderline personality disorder ↗
Study of women with BPD found that higher endocannabinoid levels appeared to buffer the link between childhood trauma and inflammation (IL-6), suggesting endocannabinoids may modulate trauma-immune interactions.
Cannabis users who cope with negative emotions showed the worst binge eating and all user profiles reported more binge eating while high ↗
Latent profile analysis of 435 cannabis users found all subgroups reported more binge eating while high, with coping-motivated users showing the worst sober eating disorder symptoms and emotion regulation difficulties.