Browse more cannabis research, findings, methods, and limitations.
A patient with suspected K2 overdose repeatedly improved with naloxone despite negative opioid and synthetic cannabinoid screens, highlighting the limitations of current toxicology testing and the potential value of naloxone in undifferentiated overdose.
A study of over 6,000 children found that maternal cannabis use around pregnancy was linked to behavioral problems specifically in children with autism symptoms, suggesting that neurodevelopmental vulnerability may modify the effects of prenatal cannabis exposure.
Five years after Canadian legalization, a longitudinal cohort showed growing social acceptance of recreational cannabis alongside increasing recognition of health risks, with non-users showing the biggest attitude shifts toward acceptance.
A natural experiment comparing Canadian and US young adults found legalization was associated with less decline in cannabis use over time (attenuated aging out) rather than increased use, with effects emerging 6-12 months post-legalization.
CBD treatment of chronic myeloid leukemia cells triggered over 3,400 gene expression changes at both 4 and 12 hours, affecting oxidative stress, p53-mediated cell death, immune signaling, and metabolic pathways.
Chronic CBD treatment increased brain copper in healthy female mice but not in Alzheimer's model mice, disrupting the coordinated regulation of metals across brain regions in the disease model, suggesting CBD's brain effects differ between healthy and diseased states.
A national US longitudinal study found alcohol and cannabis problems initially predicted fewer sleep issues but later predicted more, while people who used both consistently slept worse than the general population, suggesting a reversing relationship over time.
CBD selectively induced beneficial cell death in amyloid-beta-expressing cells while causing side effects in healthy cells, with FAAH involvement helping to rescue dysfunction in amyloid-expressing worm models, revealing context-dependent effects.
Among 860 enrollees in Illinois' opioid alternative program, medical cannabis users and non-users reported similar levels of psychological well-being, suggesting cannabis substitution for opioids neither improved nor harmed overall mental wellness.
Quality of life averaged between "good" and "fair" for all 860 enrollees in Illinois' opioid alternative program, with no significant difference between medical cannabis users and non-users.
A high-fat/high-sugar diet impaired mouse memory by overactivating the hippocampal endocannabinoid system and mTOR pathway, with CB1 receptor blockade or mTOR inhibition rescuing the memory deficits.
A narrative review outlines four key cannabis safety concerns for healthcare professionals: mood effects, suicidal ideation associations, cardiovascular effects, and drug interactions, areas where clinical awareness lags behind expanding legal access.
A study of 512 California young adults found each increase in cannabis flower potency was associated with 3.3 more use days per month and higher addiction scores, contradicting the assumption that people use less of stronger products.
A Nature Communications study found THC reaches the ovarian follicle and causes chromosome segregation errors in human oocytes, with fertility patients testing THC-positive showing significantly lower rates of chromosomally normal embryos.
Scientists discovered muscarinic cannabinoid suppression of excitation (MCSE), a new form of brain signaling where simultaneous muscarinic and cannabinoid receptor activation produces a precise ~10-minute inhibition of excitatory transmission.
Among 338 young adults, those who primarily vaped cannabis concentrates showed increasing use and problems over time, while edible users had fewer issues due to less frequent use, suggesting different consumption methods carry different addiction risks.
A 30-day tracking study found that the consequences of different cannabis consumption methods varied based on how often individuals used each method, with infrequent edible users experiencing more negative effects than frequent users.
The first trial of medicinal cannabis in teenagers with Tourette syndrome found significant improvements in tics, behavior, and quality of life, with tiredness as the most common side effect.
A 2024 review found 14 states allow recreational cannabis delivery and 26 states plus DC allow medical delivery, with wide variation in how delivery is regulated.
German survey data from 2008-2023 show stable cannabis use among adolescents but significant increases among young adults aged 18-25, providing a baseline before the country's 2024 partial legalization.
An Israeli clinic study found cannabis prescriptions varied by condition and sex: GI patients got the highest doses, men received more cannabis and higher THC content than women.
The first placebo-controlled trial of medicinal cannabis for Tourette syndrome in teenagers found the protocol was feasible, with some signal of benefit and dizziness as the most common side effect.
A review of international trends suggests Germany should expect more cannabis-related ER visits after legalization, with Canada seeing doubled hospital admissions and acute intoxication as the top reason.
A survey of nearly 83,000 Minnesota students found regular cannabis use was dramatically higher among youth with multiple marginalized identities, reaching 24.8% in one 8th-grade subgroup versus 1.8% overall.
Cell studies showed THC enhanced fat cell development and changed how fat cells handled fatty acids over time, which influenced how much fat accumulated in liver cells.
A case report documents cannabinoid hyperemesis syndrome causing lactate levels of 6.1 mmol/L, showing the condition can produce serious metabolic complications from severe dehydration and pain.
A controlled study found raw cannabinoids (CBDA, THCA) achieved 19-25x higher blood levels than activated forms (CBD, THC), and even 7.2mg of THC in a full-spectrum product caused noticeable intoxication.
A Swedish study of 7,320 people found cannabis-induced psychosis had the highest relapse rate (25.7%) among all substance-induced psychoses, with 2.42x higher risk than alcohol-induced cases.
A review of 15 studies found chronic substance use generally increases anandamide levels in the blood, suggesting the body's endocannabinoid system is disrupted across multiple types of addiction.
Combining CBD-rich cannabis oil with omega-3 fish oil prevented nerve pain and protected against nerve damage in rats, suggesting a potential combination therapy for neuropathic pain.
Among 1,568 young adults, cannabis use was linked to nearly double the binge eating rate in women (24% vs 13%) but showed no such association in men, independent of depression.
A UK early access program found pharmaceutical CBD reduced motor seizures by a median 60% at 12 months in 26 children with Lennox-Gastaut or Dravet syndrome, with 67% achieving at least 50% improvement.
In Alzheimer's mice, inhaled CBD reduced two key neuroinflammation pathways (IDO and cGAS) and lowered proinflammatory cytokines, suggesting a multi-target anti-inflammatory mechanism.
Mice lacking cannabinoid CB1 receptors on stress-related norepinephrine neurons showed altered responses to various stressors, but the direction of change depended on the specific stress context.
Germany's food safety commission found CBD supplement doses on the market can reach levels causing liver enzyme changes (4.3 mg/kg/day), while no health benefit claims were supported at any tested dose.
Mouse study found THC impairs movement by increasing inhibitory neuron activity in the prefrontal cortex and paradoxically triggering the brain's own endocannabinoid release during movement.
Massachusetts school data from 2005-2019 showed cannabis-related discipline increased 34% after decriminalization but then declined 45% after medical legalization and 20% more after recreational legalization.
A rat study found the synthetic cannabinoid CUMYL-4CN-BINACA caused dose-dependent oxidative damage, inflammation, and cell death in both brain and testicular tissue after just 14 days.
UK data from 662 osteoarthritis patients with recorded cannabis use showed they were 2x more likely to be prescribed opioids than matched non-users, though confounding likely explains much of this association.
CBD activated cellular autophagy and reduced alpha-synuclein levels in neuroblastoma cells through CB1 receptor signaling, suggesting a mechanism relevant to Parkinson's disease.
CBD protected nerve cells from a Parkinson's-relevant toxin by activating the Nrf2 antioxidant pathway, reducing oxidative stress, and preventing cell death in culture.
A systematic review found CBD targets pancreatic cancer through multiple mechanisms and enhances chemotherapy in lab studies, but no clinical trials have been conducted.
A systematic review of 19 studies found CBD killed lung cancer cells through multiple pathways, inhibited metastasis, boosted immune response, and enhanced cisplatin and radiation effectiveness.
A review of 16 studies found CBD fought liver cancer through multiple mechanisms including a specific inflammatory cell death pathway, and enhanced the effectiveness of standard drugs sorafenib and cabozantinib.
A systematic review found CBD fights gastrointestinal cancers through multiple mechanisms including cell death induction, growth inhibition, and potential enhancement of conventional chemotherapy.
In worms, blocking the enzyme that breaks down endocannabinoids protected dopamine neurons from Parkinson's-like damage through antioxidant mechanisms, with effects confirmed in a genetic knockout strain.
A survey of 109 Canadian physiatrists found most see value in medical cannabis but only 31% feel comfortable prescribing it, with insufficient medical education as the primary barrier.
Brain scans of 27 cannabis users with trauma histories showed that trauma reminders increased cannabis craving and activated reward circuits, revealing a potential neural pathway from trauma to problematic cannabis use.
A 14-day study of 590 young adults identified six patterns of substance use days, with cannabis involved in four of the six patterns and multimodal cannabis use linked to the highest stress and boredom.
A UK registry study of 64 CRPS patients found cannabis-based medicines improved pain severity, anxiety, sleep, and quality of life over 6 months, though the uncontrolled design limits conclusions.