Browse more cannabis research, findings, methods, and limitations.
Cannabis smoking consistently caused airway inflammation and bronchitis but surprisingly little evidence supported COPD or emphysema risk, and lung cancer evidence was inconclusive.
Eight heavy high-potency cannabis-dependent smokers reported visual flashbacks including illusions and color distortions persisting 3-6 months after quitting.
Review for family doctors found cannabis helped chronic/neuropathic pain with addiction risk, and highlighted cannabinoid-opioid synergy that could reduce opioid dependence.
First agonist substitution trial for cannabis dependence: dronabinol did not increase abstinence but improved retention (77% vs 61%) and reduced withdrawal symptoms.
Systematic review found 15 of 18 high-quality trials showed significant analgesic effects of cannabinoids for chronic non-cancer pain, with no serious adverse effects.
Endocannabinoid enhancement reduced depression-like behavior during nicotine withdrawal in mice through serotonin 5-HT1A receptor interaction, suggesting combined targeting for smoking cessation.
Cochrane review of 18 RCTs found emerging evidence for specialized early psychosis services but inconclusive results for cannabis-specific therapy and most other interventions.
After 3 hours in Dutch coffee shops, 50% of non-smoking volunteers tested above THC screening cut-offs in oral fluid, but the metabolite THC-COOH distinguished passive from active exposure.
Review of how prenatal cannabis and cigarettes cause lasting brain changes: cannabis altered dopamine D2 receptors through epigenetic mechanisms, potentially programming lifelong addiction vulnerability.
Review of how cannabinoids regulate nausea and vomiting, finding both THC and CBD effective through different brain mechanisms.
Tiny pilot found cannabis extract may change how COPD patients perceive breathlessness without affecting standard measurements.
Mouse study found that boosting natural endocannabinoids reduced opioid withdrawal symptoms, with the 2-AG pathway more effective than anandamide.
Review documenting that cannabis dependence and withdrawal are clinically real, though THC's slow clearance delays and obscures symptoms.
Among 109 first-episode psychosis patients, 57.8% had been previously incarcerated, with earlier cannabis use linked to incarceration history.
Review of Sativex clinical data found low intoxication, 2.2% euphoria rate, no tolerance, and no withdrawal, suggesting low abuse potential.
Lab study found cannabinoid activation protected brain cells during alcohol withdrawal, while blocking the cannabinoid system worsened damage.
The most cited paper in cannabis science: Russo's comprehensive review mapping potential terpene-cannabinoid synergies. Coined the framework for the 'entourage effect' as applied to plant medicine. THC-CBD synergy is confirmed; terpene interactions remain debated.
Rat study showed 1:1 THC:CBD combination protected brain cells from Huntington's disease-like damage through antioxidant mechanisms.
Review of Sativex clinical trials for MS spasticity showing reduced symptom severity with manageable side effects.
First reported case of cannabinoid hyperemesis syndrome in pregnancy, highlighting the need to screen for cannabis use in treatment-resistant vomiting.
Rat study found cocaine withdrawal increased cannabinoid receptors and disrupted synaptic plasticity in the amygdala, potentially driving cue-triggered relapse.
In 23 cannabis users, Sativex showed similar or slightly less abuse potential than equivalent doses of dronabinol (pure synthetic THC).
Review of 23 studies found MDMA and cannabis co-use produced additive memory deficits, involving CB1-serotonin-dopamine interactions.
Rat study found FAAH inhibitor URB597 reduced most morphine withdrawal symptoms across a broad dose range.
THC significantly reduced the brain's error-detection signal (ERN) in 10 healthy volunteers without affecting simple task performance.
A cannabinoid receptor gene variant influenced how THC affected attention-related brain waves, with CBD in cannabis extract appearing to buffer the effect.
CBD reversed amphetamine-induced oxidative brain damage and increased BDNF in rats, suggesting potential neuroprotective properties relevant to bipolar disorder.
Brain imaging showed THC increased blood flow and activity in the insula, linking this body-awareness region to the subjective experience of being "high."
Three nights off cannabis cut sleep efficiency and total sleep time and shifted REM. Extended-release zolpidem restored efficiency but did not shorten time to fall asleep.
Inpatient study found blood pressure increases up to 22.8 mmHg systolic when daily cannabis users stopped, with a subset showing potentially dangerous elevations.
Three pivotal trials totaling over 1,000 MS patients showed Sativex consistently reduced spasticity with mild, transient side effects and no abuse potential.
Review finding buspirone was the only medication with controlled trial evidence for cannabis dependence, with several others warranting further study.
Brain imaging showed THC and CBD had opposite effects on auditory processing regions, with THC's disruption correlating with psychotic symptoms.
Chronic cannabinoid exposure during rat adolescence caused temporary general cognitive impairment but spatial memory deficits lasting at least 75 days.
Review supporting cannabinoid benefits for MS spasticity, pain, and sleep, with emerging preclinical evidence for disease-modifying neuroprotection.
UK drug bulletin reviewed Sativex as add-on therapy for MS spasticity when other treatments have failed, requiring demonstration of initial response.
Late-adolescent cannabinoid exposure in rats produced recoverable general cognitive deficits but persistent spatial memory impairment lasting at least 75 days.
In 49 dependent users, greater day-to-day disruption from withdrawal was linked to relapse and to heavier use one month later.
Critical examination of the gateway drug theory, arguing that common research designs cannot adequately control for confounding factors that explain the association.
Meta-analysis of 9 studies found cannabis nearly doubles motor vehicle crash risk (OR 1.92), with higher risk for fatal crashes.
CB1 antagonist reversed nicotine locomotor sensitization in novelty-seeking rats but failed to reduce and actually worsened nicotine-induced anxiety.
Review explaining the biological rationale for why cannabis-based medicines work for MS spasticity, based on the endocannabinoid system's role in neurotransmission.
Among 1,015 substance users, 27% had headaches (94.5% starting after drug use), with cannabis use duration specifically linked to higher headache rates.
Structured interviews revealed cannabis use disorders and PTSD were significantly underdiagnosed in VA medical records for 84 military veterans.
Field sobriety tests poorly detected cannabis impairment in 20 heavy users, though the Drager oral fluid device reliably detected THC presence.
On-road driving study showed medicinal THC impaired driving in both occasional and heavy users beyond the 0.05% BAC threshold, but field sobriety tests missed it.
Comprehensive Mayo Clinic review of cannabis therapeutics, addiction, psychosis, and policy, noting the gap between public approval and scientific evidence.
New HFIP carbamate compounds inhibited the endocannabinoid enzyme MAGL with excellent selectivity, avoiding cross-reactivity with FAAH.
Beta-amyrin did not bind cannabinoid receptors (correcting prior claims) but potently inhibited 2-AG breakdown, suggesting indirect cannabinoid-based pain relief.
Brain imaging found adolescent methamphetamine and cannabis users had enlarged striatal regions and higher novelty-seeking, with meth exposure correlating to both.