Browse more cannabis research, findings, methods, and limitations.
A metered-dose cannabis inhaler reduced daily consumption by 95% (1,000 mg to 51 mg) while providing significant pain relief and high satisfaction in hospitalized patients.
Topical capsaicin for CHS in the ER did not shorten visits significantly but reduced additional medication use by 25% and lowered opioid requirements by more than half.
A Bayesian meta-analysis found current interventions for tobacco-cannabis co-users showed weak evidence for cessation of either substance, though multi-substance approaches were more promising for cannabis.
Colorado poison center data showed marijuana exposure calls stabilized after 2014 legalization overall but continued rising in children ages 0-8, driven by edible products.
THC required both CB1 and CB2 receptors for pain relief and catalepsy, while synthetic cannabinoid XLR11 needed only CB1. GPR55 deletion enhanced cannabinoid responses, suggesting it normally opposes them.
Two weeks of daily CBD altered DNA methylation at 3,323 sites in mouse hippocampus, affecting genes linked to neural development and psychiatric conditions.
GPR55 knockout mice had impaired glucose tolerance on any diet, and the weight-reducing effects of rimonabant and THCV were partly dependent on this receptor.
Chronic CBD at 50 mg/kg did not improve motor, anxiety, or cognitive measures in 4-month-old TAU58/2 transgenic male mice, despite previous success in amyloid-based AD models.
The first PET study of brain FAAH in psychosis found lower enzyme levels predicted more severe positive psychotic symptoms (large effect size), suggesting FAAH as a potential biomarker and treatment target.
US cigarette quit ratios from 2002-2016 remained dramatically lower for cannabis users (23%) and those with CUD (15%) compared to non-users (51%), with no improvement for CUD over 15 years.
Half of Colorado dispensaries recommended cannabis for glaucoma, compared to only 7.6% of glaucoma specialists, highlighting a dangerous information gap in legalized cannabis markets.
Officers at outdoor concerts had measurable airborne THC exposure and 34% had a THC metabolite in urine, but all levels were far below impairment or drug-screening thresholds.
The CB2 agonist AM1710 reversed neuropathic pain in mice with or without CB1 receptors by boosting anti-inflammatory IL-10 and suppressing pro-inflammatory cytokines in the spinal cord.
A survey of families with children who have PKAN found 39% used cannabis products after other treatments failed, with most reporting improvements in dystonia, pain, and sleep.
Electronic health record analysis found regular cannabis use was associated with higher rates of stroke, arrhythmia, and mortality, particularly in non-tobacco users.
Among nearly 12,000 children in the ABCD Study, prenatal cannabis exposure was associated with multiple sleep disturbances at ages 9-10, even after controlling for other prenatal exposures.
Analysis of online health Q&A found nearly half of provider responses about perinatal cannabis did not discourage use, and 8.8% described it as safe, revealing significant gaps in safety messaging.
A longitudinal brain imaging study of 706 teens found that cannabis-related psychotic-like experiences were partially mediated by reduced growth of the uncus in the parahippocampal gyrus between ages 14 and 19.
A CB2 inverse agonist given after prolonged seizures were stopped prevented brain inflammation, reduced neuronal death, and improved behavior in mice, suggesting a potential post-seizure neuroprotective therapy.
A comprehensive study of 8 phytocannabinoids found partial agonist activity at CB1 and/or CB2 receptors for multiple minor compounds, with several producing cannabinoid-like behavioral effects in mice.
Review found legalization increased cannabis potency and ER visits while decreasing risk perception, arguing for health-focused regulation beyond market economics.
A survey of 1,161 athletes found that attitudes about cannabis mediated the relationship between knowledge and use, with liberal-attitude athletes showing more knowledge and higher current use.
Two months of daily THC injections caused retinal damage in mice, with increased photoreceptor death driven by inflammation and oxidative stress.
Cannabis-dependent men showed worse cognitive performance under stress with reduced precuneus brain activity, despite experiencing similar levels of subjective stress as controls.
Cannabinoids stopped cocaine-induced seizures in mice by restoring glycine receptor function, working independently of CB1 and CB2 receptors through a novel molecular mechanism.
A longitudinal study of 91,774 Canadian high school students found few cannabis users quit spontaneously, but those who did showed 2.5x better attendance and 2.3x better homework completion than continuing users.
Seven days of high-dose CBD produced antidepressant-like effects in mice by increasing hippocampal serotonin and noradrenaline, the same neurotransmitters targeted by conventional antidepressants.
Genetic analysis of 11 psychiatric disorders found cannabis use disorder was significantly correlated only with ADHD, while alcohol and nicotine dependence showed broad genetic overlap with multiple psychiatric conditions.
A survey of 242 chronic pain patients in Ohio found 84% willing to try medical marijuana, 68% wanting to reduce opioids, and 94% willing to follow their specialist's guidance on concurrent use.
A 20+ year comparison of methadone clinics found cannabis use at admission increased only in Las Vegas (legal cannabis) and predicted worse treatment retention in both Las Vegas and Tel Aviv.
Review of how the endocannabinoid system modulates immune function — suppressing inflammation and showing anti-tumor effects in preclinical models.
A systematic review of 11 controlled trials found insufficient evidence for THC or CBD in schizophrenia treatment, with THC potentially worsening psychosis and CBD showing inconsistent benefits.
Longitudinal MRI study of 799 European teenagers found dose-dependent prefrontal cortical thinning associated with cannabis use from age 14 to 19, concentrated in CB1 receptor-rich brain regions.
CBD reduced the rewarding and anxiety-producing effects of the bath salt MDPV in mice, but unexpectedly increased drug-seeking in high-responding mice, revealing complex interactions.
Analysis of 2002-2014 survey data found medical marijuana laws increased cannabis use among women but did not reduce opioid misuse, with divergent effects for pregnant versus parenting women.
A meta-analysis of brain imaging studies found no significant gray matter volume differences between cannabis-using and non-using teens, but age and sex influenced subtle, region-specific patterns.
A systematic review found moderate evidence that THC reduces speed, headway distance, and reaction time while increasing lane variability in young drivers ages 15-24.
A systematic review found consistent preclinical evidence and two positive clinical trials supporting endocannabinoid system modulation for HIV-associated neuropathic pain.
Analysis of 31 light cannabis products from Italy found 87% contained pesticides and multiple heavy metals exceeding safety limits, highlighting the need for cannabis-specific regulations.
A longitudinal study found an epigenetic biomarker (cg05575921 methylation) detected both tobacco and cannabis smoke exposure in high school students, distinguishing combusted from non-combusted products.
Both cannabis and tobacco smoking activated the same inflammatory immune pathway (GPR15 on helper T cells), accounting for half of smoking's pro-inflammatory effect.
Adding CBD (200-800 mg/day) to stable SSRI treatment increased citalopram blood levels by ~50% in anxiety patients — a clinically significant drug interaction.
CBGA showed anticonvulsant effects in Dravet syndrome mice and potentiated clobazam, but was proconvulsant in another seizure model and at high doses, revealing a complex therapeutic profile.
CBDA blood levels were 14 times higher from cannabis extract than from isolated CBDA, because other cannabinoids (CBG, THC) blocked the intestinal efflux pump BCRP that normally limits CBDA absorption.
THC and CBD synergistically killed pediatric brain tumor cells in the lab through multiple mechanisms, but failed to improve survival in mouse brain tumor models, highlighting the gap between lab and clinical results.
A CBD-rich cannabis extract reduced inflammatory markers in lung cells but increased them in macrophages, highlighting the cell-type-specific and potentially contradictory effects of cannabinoids on inflammation.
A New Zealand survey found 51% of IBD patients had used cannabis, with most medicinal users reporting improvements in pain, nausea, and appetite, and 54% would request it if legally available.
An RCT of 150 autistic participants found a 20:1 CBD:THC extract improved disruptive behavior (49% vs 21%) and social responsiveness but not the primary behavioral outcome measure.
In a simulated driving study of 14 people, legal THC blood limits failed to correctly predict impairment. Nearly half exceeded the limit without being impaired, while over half were impaired when THC levels had dropped below the cutoff.
A New Zealand survey of 213 women with endometriosis found 81% reported cannabis made their pain "much better." Over three-quarters reduced their use of other medications, and 40% of stopped pain medications were opioids.