Explore published research on mental health, including study methods and limitations.
Cannabis use before age 15 was associated with 2.7-30.8 times higher odds of mental health and behavioral problems, but most of this risk was explained by pre-existing family disadvantage and early adjustment difficulties.
Case histories described bipolar patients who found cannabis useful for mania, depression, or both, with some reporting it more effective than conventional mood stabilizers.
Among drug treatment patients, 64% had alcohol dependence, 44% antisocial personality, and 24% depression. Cannabis dependence was higher in Caucasians and males, while women had higher depression and anxiety.
In 232 first-episode schizophrenia patients, cannabis preceded psychosis in one-third, coincided with onset in another third, and began after symptoms in the final third, suggesting multiple pathways.
In 50 bipolar patients, alcohol abuse correlated with time spent depressed while cannabis abuse correlated with time in mania, suggesting each substance interacts differently with bipolar mood states.
Over 15 years, cannabis abusers were four times more likely to develop depression including suicidal thoughts. Depression at baseline did not predict future cannabis abuse, arguing against self-medication.
In one of the only controlled studies of suicidal substance abusers, fluoxetine reduced depression, suicidal ideation, alcohol, and marijuana use, with benefits lasting one year.
Population-based study of 232 first schizophrenia episodes finding double the rate of substance abuse compared to controls, with cannabis used by 88% of drug abusers and drug use often preceding illness onset.
A 21-year study of 1,265 New Zealand children found cannabis use linked to crime, depression, suicidal behavior, and other drug use, with younger users (14-15) affected more than older users (20-21).
Survey of 420 MS patients finding 96% aware of cannabis therapeutic potential, 16% using it medicinally with reported improvements in anxiety, spasticity, and chronic pain.
A 2004 psychiatry review concluded that stopping heavy cannabis or THC use brings a reproducible withdrawal syndrome and proposed diagnostic criteria.
Survey of 220 MS patients finding 14% currently using cannabis for symptoms, with stress, sleep, mood, spasticity, and pain reported as most effectively relieved.
Combined cross-sectional and longitudinal study finding that psychiatric symptoms in ecstasy users were predominantly attributable to cannabis use, not ecstasy, with cessation of cannabis but not ecstasy predicting symptom remission.
Study of 357 first-episode psychosis patients found 44% met criteria for substance abuse/dependence, primarily involving cannabis and alcohol, with higher rates in younger males.
Population-based study of 133 schizophrenia patients found male cannabis users developed their first psychotic episode 6.9 years earlier than male non-users.
fMRI study found cocaine-dependent individuals who also used cannabis showed decreased frontal cortex activation during emotional stress, even after 15+ days of abstinence.
Comparative review found cannabis primarily impairs attention and memory, stimulants affect processing speed and flexibility, and heroin impacts impulse control, with severity increasing with heavier use.
UK study of 152 first-episode schizophrenia patients found 68% had lifetime drug use, with cannabis independently predicting earlier psychosis onset after adjusting for other substance use.
Vouchers drove abstinence during treatment. Adding CBT helped keep it going over the next year.
Three-year follow-up in Aboriginal communities found cannabis use decreased overall, but persistent users had higher rates of hallucinations, suicidal thoughts, and imprisonment.
Population study of 4,815 adults found cannabis use nearly tripled the risk of developing manic symptoms over 3 years (OR 2.70), independent of psychotic symptoms and with no evidence of self-medication.
Study of Nigerian army veterans from peacekeeping operations found 22% had PTSD, which was significantly associated with longer deployment, alcohol use, and lifetime cannabis use.
National survey of 43,093 Americans identified five drug abuse patterns, with cannabis-only (5.8%) being the most common and mildest, while polysubstance (0.5%) was linked to the most severe psychiatric profiles.
Study of 119 heavy cannabis users found high rates of depression (46%) and suicidality (42%), predicted by parental alcoholism and childhood adversity rather than cannabis or other drug use.
Among 757 first-episode schizophrenia cases, cannabis users and non-users showed essentially the same symptoms, arguing against a distinct "cannabis psychosis."
A clinical trial found that monthly cannabis users responded just as well to combined CBT and medication treatment for anxiety and depression as non-users.
Survey of nearly 2,000 Zambian students found 31% reported suicidal thoughts and 36% had used marijuana, with a modest but significant association between the two.
Case report of a 30-year-old whose polysubstance use (cannabis, MDMA, cocaine) led to cognitive decline, functional impairment, depression, and a suicide attempt.
Five-year follow-up of 166 bipolar patients found cannabis use specifically preceded manic episodes, while alcohol preceded depressive episodes, with neither following mood episodes.
13-year Norwegian study found frequent cannabis use linked to nearly triple the suicide attempt risk but not to depression, suggesting distinct pathways to suicidal behavior.
Frequent use and anxiety often appear together, but this 2009 review could not pin down cause and effect.
After rimonabant was pulled from the market due to psychiatric side effects, this commentary argued for continuing endocannabinoid research with better safety measures rather than abandoning the therapeutic potential of the system.
In 50,087 Swedish men followed for 33 years, the apparent link between cannabis use and suicide (OR 1.62) was fully explained by pre-existing psychological and behavioral problems (adjusted OR 0.88).
A patient experienced suicidal ideation immediately after cannabis use on two separate occasions, independent of depression or life stressors, suggesting an acute pharmacological trigger in a vulnerable individual.
Heroin users showed fearful-avoidant attachment, ecstasy users showed mixed insecure patterns, and cannabis users were mainly dismissing or secure, suggesting different drugs serve different emotional regulation needs.
Among 3,459 bipolar patients followed for 12 months, cannabis users had less treatment compliance, more mania, more psychosis, and higher overall illness severity with little evidence of confounding.
A systematic review found only 7 RCTs on treating cannabis use in psychosis/depression, with preliminary evidence supporting medication treatment of the primary disorder and longer psychological interventions.
The first case report of cannabinoid hyperemesis syndrome in a psychiatric patient highlighted that the condition may be underrecognized in mental health settings where cannabis use is common.
Among 4,075 young French adults, depression (OR ~8) and psychosocial factors predicted suicidal ideation, while cannabis use was not an independent predictor after adjustment.
Brief review linking cannabis use in adolescents to psychosis, depression, panic attacks, and suicidal thoughts.
Heavy cannabis users were slower at recognizing dynamic facial emotions, requiring greater intensity before identifying sadness, anger, and happiness.
First-episode schizophrenia patients who used cannabis showed better attention and executive function than non-users, both initially and after one year.
Comprehensive review found recreational cannabis adverse effects were generally minor, with overall harms appearing less serious than alcohol, though vulnerable individuals faced greater risks.
Survey of 1,432 Seychelles adolescents linked cannabis, alcohol, and tobacco use to suicidal ideation, truancy, and poor parental monitoring.
In Finnish teens, general anxiety predicted later substance use (via depression), while social phobia appeared to protect against persistent alcohol use.
The generic EQ-5D quality measure only moderately captured quality of life in 103 schizophrenia patients with cannabis abuse, missing domains like relationships and finances.
First documented case of marijuana-induced mania in an adolescent with no prior psychiatric history.
Cochrane review of 18 RCTs found emerging evidence for specialized early psychosis services but inconclusive results for cannabis-specific therapy and most other interventions.
Among 109 first-episode psychosis patients, 57.8% had been previously incarcerated, with earlier cannabis use linked to incarceration history.
CBD reversed amphetamine-induced oxidative brain damage and increased BDNF in rats, suggesting potential neuroprotective properties relevant to bipolar disorder.
In 49 dependent users, greater day-to-day disruption from withdrawal was linked to relapse and to heavier use one month later.
Structured interviews revealed cannabis use disorders and PTSD were significantly underdiagnosed in VA medical records for 84 military veterans.
Review finding combination therapies (motivational + cognitive-behavioral + incentives) most effective for cannabis dependence, though long-term abstinence remains below 20%.
Twin study of 5,638 found the link between borderline personality and cannabis use is genetically driven, while the alcohol connection is environmental.
Preliminary study found a serotonin receptor gene variant influenced brain activation patterns after cannabis treatment in adolescents.
In adolescents with new-onset bipolar disorder, cigarette smoking predicted development of cannabis and alcohol disorders, while quitting smoking did not worsen mood.
The most famous and debated cannabis study: 1,037 New Zealanders followed from birth showed up to 8 IQ points of decline with persistent adolescent-onset use — but subsequent twin studies and meta-analyses suggest the true effect is smaller and partly confounded.
In 1,943 Australian adolescents followed to age 29, cannabis use independently predicted self-harm (2.4x risk), with most self-harm resolving spontaneously.
College students with schizotypy traits and higher social anxiety used cannabis more frequently and reported more cannabis-related problems than those without social anxiety.
Young people seeking treatment for cannabis dependence typically had multiple psychiatric diagnoses, especially anxiety disorders like PTSD and social phobia.
Depression and insight measures distinguished cannabis-induced psychosis from primary psychotic disorders with 97% accuracy in hospitalized patients.
Eighteen months of heroin treatment reduced heroin, cocaine, and benzodiazepine use, but cannabis and alcohol consumption remained unchanged.
South African survey found high stigma toward all substance users, but cannabis was rated less dangerous than alcohol, and men faced more coercive attitudes than women.
Among 457 fibromyalgia patients, 13% used cannabinoids, with herbal cannabis use linked to mental illness, opioid drug-seeking, and male sex.
Early cannabis use was linked to a 2.9-fold increased risk of suicide attempt in French students, with different substance-suicide patterns across France and the US.
Survey of 37 medical cannabis patients found elevated psychological distress and widespread exposure to drug law enforcement tactics.
Four-year study of 1,145 college students found cannabis use predicted late enrollment gaps while depression predicted early ones.
Among 54 South African border war veterans, 33% had PTSD, and current cannabis use was the only substance significantly linked to PTSD despite high resilience.
Review found adolescent cannabis use predicts anxiety, depression, and psychosis more strongly than adult use, with earlier initiation increasing risk.
PCP users showed significantly higher rates of intimate partner violence and legal problems compared to cannabis-only and alcohol/cannabis polysubstance users.
Trait impulsivity in 385 bipolar patients was strongly linked to cannabis misuse (p<0.0001), alcohol misuse, rapid cycling, and mixed episodes, but not suicide.
Among 80 adolescents with bipolar disorder and cannabis use, 49% were heavy tobacco smokers and 70% were nicotine dependent, with smoking marking greater severity.
In a 43,070-person U.S. survey, past-year mental illness was linked to much higher cannabis use and disorder rates, and to most of the cannabis consumed.
In 76 adults with ADHD, marijuana use correlated with inattention in men and poor sleep quality in women, suggesting sex-specific effects.
In 1,803 children followed 15 years, oppositional behavior was the strongest predictor of cannabis and cocaine dependence, while the ADHD link was largely explained by opposition.
Two-year study of 976 high school students found heavy cannabis use alone predicted depression but not suicidality, while other illicit drug use predicted all three.
First Greek national survey found 14% had mental disorders, 2% monthly cannabis use, 40% smoking, with disorders frequently undertreated and comorbid.
In a study of 10,324 teens, cannabis use was linked to mental health problems, but the association was largely explained by co-occurring risk factors like truancy, alcohol, and adverse life events.
A 30-year longitudinal study found that intensive cannabis use was associated with increased suicidal ideation in males, with no evidence that suicidal thoughts drove cannabis use.
Review found about 70% of bipolar patients used cannabis, with use linked to earlier first mania and more frequent episodes, though causation remained unestablished.
Longitudinal study of inner-city youth found increasing marijuana use trajectories were associated with over 3x the odds of weapon-related violence compared to no/low use.
Among 972 high school students, cannabis use was not independently linked to suicidal ideation after controlling for borderline and psychopathic personality traits.
Among 9,288 Ontario students, about 1 in 5 had a history of brain injury, which was linked to cannabis use, mental health problems, and risky behaviors with sex-specific patterns.
Among Arkansas high schoolers, cannabis (33% ever use), inhalants (19%), and prescription drugs (13%) were all linked to suicidality, with prescription drug abuse showing the strongest association.
Across 22 longitudinal cohorts, cannabis use was linked to about 29 percent higher odds of later depression, with exposure measures often weak and overall bias rated medium.
Daily cannabis users were more likely to meet hyperactive‑impulsive ADHD symptom criteria; nondaily users showed no subtype split.
Clozapine reduced cannabis craving and insula brain activity more than risperidone in patients with schizophrenia and cannabis use disorder over 4 weeks of treatment.
Among 290 adolescents with eating disorders, nearly half of those with bulimia nervosa reported substance use, with older age being the strongest predictor of regular use.
Longitudinal study found marijuana use predicted dating aggression in girls, hard drug use predicted it in boys, and alcohol predicted aggression timing for both sexes across grades 8-12.
Systematic review found that exercise, massage, acupuncture, several medication classes, and lifestyle factors all upregulate the endocannabinoid system, relevant to conditions like migraine and fibromyalgia.
Positive schizotypy, not cannabis use, predicted creativity. Cannabis was only associated with divergent thinking in people who scored low on baseline creativity measures.
RCT of 185 patients found an 8-session CBT intervention did not outperform treatment as usual for substance users with suicide risk on any measure over 6 months.
Population study of 1,560 young adults found lifetime crack cocaine use (2.5% prevalence) was associated with PTSD, antisocial personality disorder, suicide risk, and polysubstance use including cannabis.
RCT of 764 students found the Climate Schools online prevention program reduced truancy, psychological distress, and moral disengagement for up to 12 months.
Canadian study found teens with ADHD reported cannabis use at 14.2%, comparable to or lower than the 16.5-26.0% rates in two general population samples.
Heavy cannabis users showed altered connectivity in self-awareness brain networks, linked to less anxiety but worse memory, that partially persisted after one month of abstinence.
Prospective study of 2,042 Chilean adolescents found cannabis misuse independently predicted new self-harm onset over 6 months, alongside depression, suicidal thoughts, and poor problem-solving.
Among 502 first-episode psychosis patients, cannabis users who reduced or stopped use after treatment contact showed the greatest symptom improvement at one year.
Population survey of 4,014 Ontario adults found those screening positive for ADHD reported more substance use but no more collisions or driving after drinking or cannabis use.
In nearly 5,000 young Swiss men, cannabis use and depression predicted later disengagement from work and school, but being disengaged did not predict later substance use.
In 110 people with early psychosis and cannabis dependence, reducing cannabis was linked to lower anxiety and better functioning, but not to changes in core psychotic symptoms.
2015 review: CBD was linked to lower anxiety in acute tests. Long-term treatment evidence in diagnosed patients was thin.
In 35 cannabis-dependent patients, psychiatric symptoms improved with effect sizes of 0.7-1.4 within 16 days of inpatient detox, though patients self-reported more distress than clinicians observed.
Among 678 young French smokers, cannabis use in the prior year and financial difficulties were the strongest barriers to sustaining tobacco cessation for 12 months.
In 9,583 Australian twins, cannabis involvement was modestly associated with suicidal ideation and unplanned attempts, partly explained by shared genetic and environmental vulnerabilities.
Veterans of Iraq and Afghanistan described cannabis as more effective and less problematic than alcohol or prescriptions for PTSD, with coping patterns ranging from approach to avoidance.
Longitudinal study of 816 people found externalizing disorders (conduct problems) predicted cannabis use disorder onset from ages 16-30, while depression and anxiety did not.
Among 140 Mexican suicide attempters, males were significantly more likely to use cannabis and alcohol with substance-related diagnoses, while females had stress-related diagnoses.
Systematic review and meta-analysis found cannabis use associated with ~3x increased risk of new manic symptoms and worsened mania in existing bipolar disorder.
Survey of 255 French medical students found cannabis users failed exams at 89% vs. 39% for non-users, with 10% of all students reporting suicidal ideation.
Among 371 juvenile detainees, cannabis use was 54% lifetime and 16% daily, far above general population rates, with daily users showing worse mental health but not more criminal involvement.
Among 96 bipolar manic patients, the dysphoric-psychotic subtype had higher rates of combined alcohol-cannabis use disorders and more suicide attempts than the pure elevated mania subtype.
U.S. adult cannabis use more than doubled by 2012-2013. Use disorders nearly doubled in the population, while the share of users with a disorder fell from 36% to 31%.
Heavy adolescent marijuana users showed disrupted emotional development (no improvement in negative emotionality or resilience), with brain activation differences mediating the outcomes.
Study of 101 incarcerated Indigenous Australian men found family responsibilities and incarceration were the strongest motivators for quitting cannabis, suggesting culturally tailored cessation programs are needed.
24-month study found regular cannabis use significantly lowered remission rates in bipolar spectrum disorders, with the worst outcomes among those using both cannabis and tobacco.
School-based program targeting personality risk factors delayed cannabis use in high-risk teens, with sensation-seekers 75% less likely to start using over 24 months.
Canadian national survey found 3.9% past-year depression prevalence, with about 5% of depressed individuals also having cannabis use disorders. 63% sought treatment but 38% perceived stigma.
First-grade attention problems predicted marijuana use by seventh grade in African American youth, while externalizing behavior predicted drug exposure opportunities during the high school transition.
Among homeless people in BC, cannabis users had 32% psychotic disorder rates linked to childhood neglect, while stimulant users were more likely female and poly-substance users.
fMRI study found 14-year-old cannabis users had exaggerated amygdala reactivity to angry faces and impaired cortical threat regulation compared to matched non-users.
Bipolar patients who quit cannabis during a manic episode had outcomes similar to never-users over two years, while those who continued using had lower recovery, higher recurrence, and more work impairment.
Among 100 hospitalized male bipolar patients, current substance use tripled violence risk, with cannabis, alcohol, and synthetic cannabinoids as the most common substances.
A clinical review found cannabinoids offer modest benefits for nausea and inconsistent benefits for pain, while risks include cognitive impairment, driving accidents, dependence, and psychosis.
A review found minimal evidence for prenatal cannabis exposure causing childhood aggression, and only a marginal, largely confounded association between adolescent use and aggressive behavior.
Among 210 people with gender dysphoria, 31.4% had social anxiety disorder, with current cannabis use nearly quadrupling the odds in multivariable analysis.
A study of 34,000+ US adults found cannabis use predicted a 6.2x higher risk of substance use disorders over three years, but was not associated with mood or anxiety disorders.
A meta-analysis found cannabis use associated with 2.6x suicide death risk, 1.4x suicidal ideation risk, and 2.2x suicide attempt risk, with heavy use approximately doubling these figures.
A case report described CHS being mistaken for eating disorder purging in a patient with a real history of anorexia nervosa, diagnosed only after collateral history and drug screening.
Genetic risk scores for schizophrenia predicted cannabis and cocaine involvement, while depression genetic risk predicted cannabis use and severe cocaine dependence, in 2,573 participants.
In 116 veterans attempting cannabis cessation, PTSD symptoms predicted declining friend support over 6 months, but only among those who relapsed in the first month.
Among nearly 30,000 adults over 50, marijuana-only users had 1.5x higher odds of depression vs. non-users, though they fared better than users of other illicit drugs.
Among 273 pregnant former smokers, 14% had a lifetime cannabis use disorder, with having multiple psychiatric disorders as the overwhelming strongest predictor (36x odds).
National survey data from 2002-2014 showed probationers and parolees had substance use disorder rates four to nine times higher than the general population, with marijuana dependence significantly elevated but still less common than alcohol disorders.
A 3-year prospective study of the US population found cannabis use was not associated with increased risk of developing anxiety disorders, though people with panic disorder were more likely to start using cannabis.
A study of nearly 10,000 Australian twins found that while lifetime cannabis use and self-injury share genetic roots, early cannabis use before age 17 appears to carry independent risk for self-harm even after accounting for genetics.
A case report describes how cannabinoid hyperemesis syndrome in a bipolar patient caused three weeks of vomiting that lowered mood stabilizer levels, likely triggering a manic episode.
The first nationally representative US study using DSM-5 criteria found 2.5% of adults had a past-year cannabis use disorder, with strong links to psychiatric comorbidity and disability, yet only 13% ever sought treatment.
Network analysis of environmental risk factors found that cannabis use had the most direct connections to psychosis symptoms, with pathways often running through other psychiatric symptoms like anxiety and hostility.
A survey of 5,080 Canadian adults found that hyperactive/impulsive ADHD symptoms predicted problematic cannabis use in men, while inattentive symptoms predicted it in women, revealing sex-specific pathways.
MRI study found cannabis use was associated with thinner frontal cortex in young adults, with distinct brain structure patterns emerging in cannabis users who also had persistent ADHD.
First systematic analysis of online forums found 25% of posts claim cannabis helps ADHD versus 8% saying it is harmful, despite zero clinical evidence supporting cannabis as an ADHD treatment.
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.
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.
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.
fMRI study finds heavy cannabis users show reduced medial prefrontal cortex activity during conscious emotional evaluation of both positive and negative content.
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%).
A 25-year cohort study found childhood conduct problems and adolescent attention difficulties independently predicted problematic cannabis use by age 25.
In identical twin pairs, the twin who used cannabis frequently was about twice as likely to have depression and 2.5 times as likely to report suicidal thoughts, even after controlling for shared genetics.
Suicide attempts predicted later development of substance dependence (including cannabis), but early substance use showed limited evidence of predicting future suicidal behavior.
Prospective study of young Mexicans found cannabis use before age 15 was associated with nearly 4x risk of suicidal ideation and 5x risk of suicide attempt over eight years of follow-up.
In a 20-year cohort study, adolescent self-harm independently predicted weekly cannabis use at age 35, the only outcome that survived adjustment for adolescent mental health and behavior problems.
Daily cannabis use predicted suicidal ideation through feeling like a burden to others, but only when combined with feeling disconnected, supporting a psychological theory of cannabis-related suicide risk.
Cannabis use disorder diagnoses in US hospitals nearly tripled from 2002-2011, with psychiatric disorders as the top comorbidity and patients trending older and sicker.
Synthetic cannabinoid users showed significantly worse executive function, memory, and mental health compared to both recreational cannabis users and non-users across two countries.
Review arguing that cannabis harms mood, cognition, psychiatric health, and driving, and that public perception of low risk is unsupported by the scientific evidence.
Narrative review finding substantial evidence linking cannabis to psychosis and other drug use, mixed evidence for depression and anxiety, with adolescent onset carrying the greatest psychiatric risk.
20-year cohort study of 1,229 people identifying distinct risk profiles for persistent (6.7%), limited (13.3%), and delayed (3.7%) problematic cannabis use, with anxiety predicting persistence and childhood trauma predicting late onset.
Study of 302 adults finding that reducing cannabis use over 12 weeks improved anxiety, depression, and sleep quality but not overall quality of life, with effects independent of other substance use changes.
Study of 3,233 veterans finding cannabis use disorder independently associated with 2.3 times higher odds of suicide attempts, even after controlling for PTSD, depression, and other substance use.
Study of 721 people finding sober cannabis users appeared more creative, but this was entirely explained by their higher levels of openness to experience rather than any effect of cannabis.
Screening of 22,095 primary care patients in Washington State finding 15.3% past-year cannabis use and 3.1% daily use, with rates reaching 36% among young adults and 32% among young men with depression.
Comprehensive review finding strong evidence from human and animal studies that adolescent cannabis exposure causes lasting deficits in cognition, emotion, and psychosis risk that do not occur with adult-onset exposure.
Survey of 271 Canadian medical cannabis patients finding 63% used cannabis as a substitute for prescriptions (30% opioids, 16% benzodiazepines), with 42% also buying from illegal sources.
Rat study showing CB1 inverse agonists produce impulsivity only when serotonin is disrupted, explaining why rimonabant caused suicidal behavior in a vulnerable subpopulation and suggesting neutral antagonists are safer.
Validation of a new 46-item questionnaire identifying six categories of cannabis cessation expectations, providing clinicians a tool to understand barriers to quitting.
Review of randomized trials of plant-based cannabis (excluding synthetics) for psychiatric and neurologic conditions finding limited evidence across conditions, highlighting the gap between policy approval and clinical evidence.
Review arguing that cannabis and stimulant drugs damage well-being through the same core mechanism: cyclical mood disruptions that chronically stress the body's hormonal and neurological systems.
Among 302 adults entering cannabis treatment, women had significantly more severe withdrawal, more psychiatric disorders, and more pain than men despite identical cannabis use patterns.
Systematic review of 52 Indian studies found high co-occurrence of cannabis and psychotic disorders, but nearly all studies used male-only samples and none adequately explored causation.
Review finding cannabis showed benefits for MS, Parkinson's, ALS, and late-stage Alzheimer's, but increased positive symptoms in schizophrenia and worsened bipolar disorder.
Survey of 7,488 African American students found 18.5% past-year marijuana use, with parent, teacher, and school protective factors significantly reducing risk.
Colorado data showed marijuana-related hospitalizations doubled, ER visits had 5x higher mental illness rates, and poison control calls surged after both medical and recreational legalization.
Brain imaging showed regular cannabis users had impaired ability to downregulate negative emotions, with disrupted amygdala-prefrontal cortex communication during regulation tasks.
Over 12 months, depressed outpatients who used marijuana non-medically showed less improvement in depression and suicidal ideation and attended fewer psychiatry visits.
Adults with ADHD used cannabis at 3x the rate of those without, with the hyperactive subtype starting at age 13.8 versus 16.3 for inattentive, and 4x higher personality disorder rates.
Systematic review of 108 studies found consistent links between substance use (including cannabis) and suicidal ideation and behavior across low- and middle-income countries.
National study tracked marijuana transitions: 2.4% of never-users initiated, 10.4% of former users returned, and 72.5% continued over one year, with early initiation and frequent use predicting persistence.
Overview found cannabinoids produce dose-dependent acute effects on anxiety, mood, and cognition, with chronic use linked to tolerance, dependence, withdrawal, and associations with psychiatric disorders.
Population study of 3,723 people with anxiety disorders found cannabis use did not predict worse remission after adjusting for baseline differences, though cannabis use disorder linked to relationship and educational disruption.
Pilot study of 25 adolescent psychiatric inpatients found 76% substance use and 36% illicit drug use, with cannabis predicted by family dysfunction and substance use linked to suicidal ideation.
Survey of 1,666 IBD patients found marijuana users reported high perceived benefits (80.7%) but also had more depression, anxiety, and pain than non-users, likely reflecting harder-to-treat disease.
Cannabis use disorder was the only factor consistently associated with self-injury across all models in Iraq/Afghanistan veterans, with odds ratios of 3.10 for suicidal and 5.12 for nonsuicidal self-injury.
Population survey of 5,196 adults found ADHD did not predict arrest history, but cannabis misuse did, with a stronger effect in women than men.
Critical review found CBD shows distinct promise for psychosis, anxiety, and withdrawal symptoms, each through different pharmacological mechanisms, but needs larger controlled trials.
Study of 203 daily cannabis users found that the tendency to experience negative emotions explained why people with low distress tolerance have more cannabis problems, worse withdrawal, and less confidence in quitting.
Study of 459 SUD patients found a graded pattern: childhood trauma plus PTSD showed the worst cannabis and psychiatric outcomes, trauma-only was intermediate, and no-trauma had the best outcomes.
Study of 214 transgender women found daily marijuana use was the only substance linked to HIV risk behavior during sex, but only among those with higher overall marijuana use rates.
MTA follow-up found adults with ADHD who persistently used substances perceived cannabis as improving both mood and ADHD symptoms, though broad substance-mood perceptions did not differ from non-ADHD users.
Study of 265 early psychosis patients found CUD was a significant violence risk factor, with two high-risk profiles: CUD + impulsivity, or CUD + lack of insight + non-adherence. Good insight and adherence moderated the risk.
Largest cannabis GWAS (184,765 people) found 8 significant variants, CADM2 as the top gene, 11% heritability, and Mendelian randomization evidence that schizophrenia risk causally increases cannabis use.
ADHD adolescents with cannabis use disorder had higher hospital costs, longer stays, and 17-fold higher alcohol abuse risk, but received 55% less psychiatric medication and 59% less behavioral therapy.
Analysis of 405 psychiatric outpatients identified four distinct profiles of co-occurring substance use and mental health symptoms, with cannabis use prominent in three of the four groups.
French university students with ADHD (5.6%) had significantly higher rates of cannabis, alcohol, and tobacco use plus behavioral addictions, and were more likely to struggle academically.
Among 1,790 psychosis patients, daily cannabis use was linked to suicide attempts only until depression, loneliness, and homelessness were accounted for, suggesting these factors drive the apparent association.
Brazilian national survey found cannabis users had three times the rate of suicidal ideation (31.5% vs 9.9%) and suicide attempts (16.5% vs 5.4%), persisting after controlling for depression.
Among 319 Iraq/Afghanistan veterans, cannabis dependence was associated with nearly 8-fold increased odds of post-deployment suicide attempts, independent of PTSD, depression, and other substance use.
A review of cannabis evidence for autism found only five small studies and mixed results for all conditions except epilepsy, highlighting a major gap between anecdotal reports and scientific evidence.
In a year-long study of 545 at-risk military personnel, marijuana use combined with high PTSD symptoms predicted worsening PTSD and increased suicidal behavior, an interaction not seen with alcohol or opioids.
In 60 children with autism and severe behavioral problems, CBD-rich cannabis improved behavioral outbreaks in 61% with mostly mild side effects, supporting feasibility of controlled trials.
A review found the endocannabinoid system may contribute to bipolar disorder pathophysiology, with CB2 receptor activation emerging as a potential mood-stabilizing target, though evidence remains limited.
Among 230 schizophrenia patients in Pakistan, ongoing cannabis use was linked to treatment resistance even after excluding non-adherent patients, with over 60% of the cohort being treatment-resistant.
A systematic review found strong biological rationale and patient reports supporting cannabinoids for Tourette syndrome, but only two small trials exist, leaving efficacy and safety largely undetermined.
In a prospective study of 188 autism patients treated with CBD-rich cannabis oil for six months, 84% of those assessed reported improvement, with mostly mild side effects and high treatment continuation.
A Lancet meta-analysis of 83 studies found scarce evidence that cannabinoids help depression, anxiety, PTSD, or other mental disorders, with THC products doubling adverse event rates versus placebo.
A systematic review of 1,301 papers found only 27 qualifying studies of CBD for psychiatric disorders, with limited but promising signals for substance use, psychosis, and anxiety.
Cannabis use predicted suicidal ideation, planning, and attempts in 451 Latinx LGB teens, with the strongest association (OR 3.12) for actual suicide attempts.
A study of 86,254 teens across 21 countries found cannabis use approximately doubled the odds of suicide attempts, with the association consistent across countries with widely varying cannabis prevalence.
A review for pediatric gynecologists found adolescent marijuana use carries risks for brain development, reproductive health, and mental health, with limited research on gynecological-specific effects.
Past-year marijuana use nearly doubled among former US cigarette smokers from 2002-2016, while depression and binge drinking also rose, threatening sustained smoking cessation.
Among 12,642 teens, bullies and bully-victims had higher marijuana use, but stronger parent and peer attachments significantly reduced this risk, suggesting targets for prevention programs.
Review of evidence suggesting CBD has antipsychotic properties through a unique non-dopamine mechanism, potentially offering a new treatment class for psychotic disorders with fewer side effects.
Retrospective study of 1,661 psychiatric inpatients found synthetic cannabinoid users didn't have longer stays or need higher antipsychotic doses than cannabis users, while both groups had shorter stays than non-drug users.
Comprehensive review finding CBD has established efficacy for epilepsy, early clinical signals for anxiety and psychosis, and preclinical-only evidence for depression and Alzheimer's.
Longitudinal study of 4,975 young men found ADHD predicted persistent risky alcohol and nicotine use but was associated with maturing out of risky cannabis use over 15 months.
Observational study of 18 autism patients found CBD-rich cannabis extract (75:1 CBD:THC) improved symptoms in 14 of 15 who completed 6-9 months of treatment, with strongest gains in seizures, ADHD, sleep, and social interaction.
Study of 5,622 Canadian youth found depression, anxiety, and drug disorders linked to being out of school and work, but cannabis use disorder showed no association at all.
Meta-analysis of 23,317 individuals found adolescent cannabis use linked to 37% higher depression risk and 3.46x higher suicide attempt risk in young adulthood, even after accounting for pre-existing mental health.
Clinical review for psychiatrists finds synthetic cannabinoids cause faster dependence, worse psychiatric symptoms, more dangerous withdrawal, and physical effects including seizures and death compared to natural cannabis.
Canadian study of 43,466 people found women who use cannabis regularly experience significantly more psychological distress and suicidal thoughts than men who use at the same frequency.
Review finds the cannabis-schizophrenia causal hypothesis remains unproven after decades of research, with three competing explanations and significant gaps in social, cultural, and non-Western evidence.
Study of 401 at-risk teens found 74% maintained low cannabis use, with boys more likely to show chronic or escalating patterns and conduct disorder showing the strongest bidirectional link to problematic use.
Systematic review of 14 RCTs (1,629 participants) finds cannabis-based medicines improved symptoms across multiple mental disorders as adjuncts but achieved no remissions, with larger trials needed.
Five-year case report of Finnish adult ADHD patient who found medical cannabis (THC-dominant plus THC/CBD blend) more effective than Ritalin for emotional regulation, anger, and concentration.
Study of 1,661 Australian teens found 10% used multiple substances, with depression, conduct problems, and school environment as the strongest predictors, suggesting prevention should target mental health.
Motivational therapy sessions with 56 frequent cannabis-using teens found emotional coping was the main use driver, with most identifying education, career, and family as values they saw cannabis use conflicting with.
Systematic review of CBD in psychiatry finds limited evidence for cannabis withdrawal, addiction, psychosis, and social anxiety, with few side effects.
Review of animal and human studies finds cannabinoid-facilitated extinction of traumatic memories with large effect sizes, acting through prefrontal cortex, amygdala, and hippocampus.
Review finds limited support for cannabis benefits in mental illness, growing evidence of harm in psychosis and mood disorders, and proposes a framework for understanding addiction vulnerability.
Cannabis-related psychiatric disorders tied with schizophrenia (31.6% each) as the leading reason for psychiatric hospitalization at a South African mental health unit.
Birth cohort study found cannabis use at 16 approximately doubled the odds of a first suicide attempt by 21 among adolescents with suicidal thoughts or self-harm.
Study of 98 Tourette syndrome patients found 85% reported tic improvement with cannabis-based medicines, with patients preferring THC-rich medicinal cannabis over pharmaceutical alternatives.
Study of 4,028 adults with congenital heart disease across 15 countries found cannabis-only use had negligible impact, while cannabis-tobacco co-use moderately worsened mental health.
In 404 first-episode psychosis patients, tobacco, alcohol, and cannabis use each predicted worse treatment outcomes over two years, with tobacco linked to the most negative effects.
In a large Asian multi-country study, schizophrenia patients with lifetime cannabis use had higher rates of aggressive behavior and were more likely to receive long-acting injectable antipsychotics.
A review maps cannabis-related psychosis through DSM-5 categories, showing a continuum from intoxication to cannabis-induced psychotic disorder to schizophrenia.
Among Canadian university students, 11% used cannabis medicinally (mostly for mental health), 38% replaced prescribed medications, and 14% met criteria for cannabis use disorder.
Structured clinical interviews of 100 dispensary users found high rates of anxiety disorders and substance abuse, with many endorsing psychological symptoms.
Latent class analysis of 329 weekly cannabis users found those with stronger use motives had more psychosis symptoms, depression, anxiety, and reckless behavior.
A narrative review found consistent evidence linking adolescent cannabis use to alterations in brain structure, function, and connectivity, with some changes appearing to persist into adulthood.
A longitudinal study of 1,606 Quebec adolescents found depression predicted subsequent weekly cannabis use, while the link between cannabis and suicidal ideation was fully explained by other substance use.
A cross-sectional study of 1,462 Colombian high school students found lifetime cannabis use associated with 1.88 times the odds of high suicide risk, though the study could not determine direction of the relationship.
When Italy accidentally liberalized CBD products in 2017, prescription sales of anxiolytics, sedatives, opioids, antidepressants, and antipsychotics dropped significantly in provinces where the products became available.
A study of 128 participants found chronic synthetic cannabinoid users had higher neuroticism, lower agreeableness, and greater schizotypal traits than natural cannabis users or non-users, suggesting SC users may be more psychiatrically vulnerable.
A leading endocannabinoid researcher describes the expanded endocannabinoidome as a platform for non-psychoactive cannabinoid therapies and highlights its connection to the gut-brain axis in neuropsychiatric disorders.
Among veterans with cannabis use disorder, 79% had a co-occurring mental health disorder and 77% had another substance use disorder, with comorbid conditions driving greater mental health service use.
Prospective study of 214 first-episode psychosis patients found continued cannabis use was associated with increased depression in those with high insight and medication adherence after one year.
Prospective study found 21% of first-episode schizophrenia patients had breakthrough psychosis despite long-acting antipsychotic injections, with cannabis use as an independent predictor.
Cross-sectional study of Canadian students found feeling connected (relatedness) and capable (competence) were linked to less cannabis and alcohol use, while autonomy was linked to more use.
Small retrospective study found 47% of first-episode mania patients who were screened tested positive for cannabis, higher than general population rates.
Multisite study of 948 psychosis patients across 6 countries found those who used cannabis had better premorbid social functioning, suggesting social ability may have facilitated cannabis exposure.
National Canadian survey found 72% of people with cannabis dependence history achieved remission, but only 43% reached positive mental health, compared to 74% without dependence history.
Systematic review of 8 studies with 210 participants found limited evidence for CBD as an antipsychotic but noted its favorable side effect profile compared to standard medications.
Ontario study found frequent cannabis use in youth aged 12-17 was associated with elevated anxiety, depression, and behavioral symptoms, with associations 2-3 times stronger in girls than boys.
National survey of nearly 88,000 adolescents found cannabis use linked to higher depression and suicide attempts, but the relationship between use frequency and depression was unexpectedly non-linear.
Study of 165 schizophrenia patients found substance use disorder quadrupled self-harm risk, with cannabis and synthetic cannabinoids most commonly abused among those who self-injured.
Canadian survey data shows the association between monthly cannabis use and depression/suicidal ideation strengthened from 2002 to 2012, with monthly users in 2012 having ~1.5 times the odds of both outcomes vs 2002 users.
Umbrella review of 26 meta-analyses confirms cannabis use is linked to increased psychosis risk, dose-dependent onset, earlier presentation, and higher relapse rates in psychotic patients.
Meta-analysis of 15 controlled studies confirms THC induces psychotic, negative, and general psychiatric symptoms with large effect sizes in healthy people, while CBD shows no consistent protective effect.
Survey of 166 Iranian university students found that personal attitudes and perceived control, not peer pressure, were the strongest predictors of marijuana use intentions.
Longitudinal study of 437 homeless adults in Vancouver found that co-occurring substance use and psychotic disorders were associated with the highest mortality risk over 10 years.
Small RCT with 14 OCD patients found no significant symptom reduction from acute smoked cannabis (THC or CBD) versus placebo, though CBD showed a trend toward reduced anxiety.
Systematic review of 23 studies found CBD most promising for anxiety and as adjunct treatment for psychosis, with limited evidence for depression and PTSD.
Canadian national survey of 24,089 people found cannabis use was associated with a weaker link between PTSD and both severe depression and suicidal ideation.
Systematic review of 25 CBD studies (927 patients) found the best evidence for anxiety and psychosis, with wide dosing variation and generally mild side effects.
Six-week RCT of 65 overweight adults found 15mg daily CBD hemp extract significantly improved HDL cholesterol, with trends toward better sleep and stress coping.
Study of 106 psychiatric inpatients found 25.5% used cannabis the week before admission, but psychotic diagnosis, not cannabis dose, was the main predictor of symptom severity.
Study of 99 cannabis treatment seekers found ADHD prevalence of 34-46%, far exceeding general population rates, suggesting routine ADHD screening should be standard.
Study of 431 chronic pain patients found emotion dysregulation explained the link between cannabis use problems and anxiety, depression, and suicidal ideation.
Systematic review found 10 of 12 studies support a cannabis-psychosis link, with THC identified as the primary risk and CBD as potentially therapeutic.
Study of 1,008 adults found cannabis misuse predicted ADHD symptoms (hyperactive and inattentive) but not other cognitive deficits; age of first use showed no cognitive effects.
A 15-year-old with autism showed unexpected improvements in core social deficits, anxiety, and sleep on low-dose CBD extract originally prescribed for epilepsy.
Analysis of 410,138 NSDUH respondents found cannabis exposure tracked with all four mental health indices, with serious mental illness doubling as use increased and legalization linked to 12.91% attributable fraction.
Eleven-year study of 1,457 Hispanic youth found high school discrimination predicted marijuana use initiation and continuation into emerging adulthood.
Systematic review found prenatal cannabis exposure may be linked to ADHD and affective symptoms in offspring, but the topic is under-researched despite common use.
Systematic review found THC impaired facial emotion recognition in half of experiments while CBD improved it, with opposing brain activation for threatening faces.
First clinically-focused systematic review found CBD tentatively supported for social anxiety and adjunctive schizophrenia, with high-THC showing no depression benefit.
Study of 71 schizophrenia patients found lifetime cannabis users had greater deficits in emotional expression, anticipatory pleasure, and social functioning.
Study of 2,545 cannabis users found impulsivity and coping motives predicted heaviest use (daily, 4+ times), with 36% of users in the highest frequency group.
Case of severe treatment-resistant OCD markedly improving with medicinal cannabis, adding to 3 total case reports supporting a cannabinoid hypothesis of OCD.
A South African study found 55.6% of patients with psychotic disorders had co-occurring substance use disorders, with cannabis use disorder being the most common at 34.3%.
A secondary analysis of 302 adults in a cannabis cessation trial found that depression predicted less abstinence (especially in women) and that depressive symptoms preceded increased cannabis use, not the other way around.
Cannabis use and subclinical psychosis traits showed consistent positive correlations in the general population, with one significant genetic link: social anhedonia was inversely correlated with cannabis use frequency.
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 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.
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.
A daily diary study of 97 young adults found that cannabis-related enhancement and social motives were the primary drivers of same-day alcohol and cannabis co-use, more so than alcohol-related motives.
A review of 10 clinical studies found CBD may reduce psychotic symptoms caused by THC and positive symptoms of schizophrenia, though results for treating cannabis use disorder were mixed.
CBD's proven success treating severe epilepsy has opened the door to investigating its potential for depression, anxiety, PTSD, addiction, and autism. Preclinical and early clinical data show promise across multiple neuropsychiatric conditions.
A study of 152 youths found that more severe cannabis use disorder was linked to poorer recognition of sad and fearful facial expressions, independent of conduct disorder. This could represent a pathway through which cannabis increases aggression risk.
In a study of nearly 3,000 people with psychotic disorders, cannabis users had lower quality of life and worse functioning. Neither starting nor stopping cannabis changed outcomes within one year, suggesting accumulated effects from years of use.
A study of 703 adolescents found cannabis use linked to specific DNA methylation changes in immune cells. Notably, patterns in T cells and monocytes overlapped with brain tissue findings from psychosis research.
Tracking 552 young cannabis users from age 19 to 22, psychotic-like experiences did not predict changes in cannabis use, but later age of first use predicted steeper increases.
Analysis of 3,785 Australian twins found five drug use patterns, with persistent polydrug use showing 94% heritability and links to conduct and antisocial personality disorders.
Study of 307 healthy adults found no link between cannabis use and Kamin blocking (an associative learning task impaired in schizophrenia), though current users reported more schizotypy and aberrant salience.
Pilot RCT of CBD in eight children with intellectual disability found 100% adherence, no serious side effects, and a preliminary signal of benefit for severe behavioral problems.
Survey of 239 young LA cannabis users found CBD-dominant product users were more medically motivated and reported more pain, but also used more illicit drugs, especially psilocybin.
Study of 863 Spanish adolescents found girls had higher mental health-substance use comorbidity, with depression predicting cannabis use disorder and obsessive-compulsive symptoms predicting alcohol use disorder.
Study of 5,792 high schoolers found earlier substance use predicted emotional detachment from parents, which in turn predicted progression to illicit drugs like cocaine and hallucinogens.
Survey of nearly 3,000 Czech and Slovak university students found tobacco and cannabis use both correlated with alcohol use disorders, with males at higher risk, during early COVID-19.
Qualitative study found mental health professionals who use cannabis recognized psychological risks but may underestimate physical health harms, suggesting need for professional education.
Daily diary study of 62 cannabis users found those with more ADHD symptoms experienced more daily cannabis consequences, with boredom and sleep motives increasing problems further.
Analysis of 281,650 young adults found cannabis use disorder was associated with higher suicidality regardless of depression, with women showing significantly stronger associations than men.
National survey of 4,069 veterans found 11.9% cannabis use overall, rising to 24-30% among those with psychiatric conditions, with depression independently tripling CUD risk.
Study of 4,069 veterans found cannabis use disorder was more strongly associated with suicidal ideation and planning than alcohol use disorder alone, independent of psychiatric and trauma factors.
Study of 3,157 veterans found cannabis use and cannabis use disorder were associated with 1.5 to 8.3 times higher odds of psychiatric conditions, suicidality, and treatment utilization.
Mendelian randomization found genetic liability to bipolar disorder increased cannabis use risk, but genetic liability to cannabis use did not increase bipolar disorder risk, suggesting a self-medication pathway.
Scoping review of only 6 studies found cannabis use was mostly not associated with cognitive impairment in bipolar disorder, with two studies finding better performance in some domains.
National study found emerging adults, men, Black/African American, Native, and sexual minority groups had the highest risk of co-occurring cannabis use disorder and suicidality.
Community study of 2,142 people found heavy drinking, cannabis use, and stressful events each independently predicted psychosis, with two co-occurring risk factors raising incidence from 1.6% to 17.7%.
Review of 37 studies found men are twice as likely to have CUD overall, but certain mental illnesses (anxiety, antisocial personality) reverse or narrow the sex gap.
A study of 70 young frequent cannabis users found those with higher trait mindfulness reported fewer cannabis-related problems, though mindfulness did not predict motivation to reduce use.
A chart review of 50 ADHD patients found heavy cannabis use was associated with significantly worse cognitive test performance, more fine motor hyperactivity, and higher self-reported impulsivity compared to ADHD patients without substance use.
A national study of 37,870 high school students found sexual minority girls had higher odds of marijuana use while sexual minority boys had lower odds, revealing important sex-based differences in substance use patterns.
A study of 5,987 young Swiss men found four distinct cannabis use disorder trajectories from ages 20-25, with mental health problems and peer drug use predicting who remained stuck at high severity.
Among 239 ADHD patients with substance use disorders, those seeking cannabis treatment had more anxiety, earlier substance use onset, and similar ADHD severity compared to those seeking cocaine treatment.
Cannabis use before first psychiatric hospitalization in Ontario rose from 17% to 26% over a decade, with nearly half of young adults (18-24) using cannabis before admission by 2017.
A meta-analysis of 31 randomized controlled trials found only limited evidence that cannabinoid products help with certain psychiatric symptoms short-term, and no evidence for mid- to long-term effectiveness for any psychiatric disorder.
An Australian cohort study spanning 16 years found persistent cannabis, tobacco, and binge drinking from adolescence through young adulthood predicted gambling problems in the early 30s.
A study of 101 low-income pregnant women found sexual partner violence predicted marijuana use during pregnancy, while physical violence and childhood adversity predicted cigarette use at different intensity levels.
A study of 605 young adolescents (mean age 13) found cannabis users scored much higher on hopelessness, depression, and anomalous reality perception, with hopelessness being the strongest unique predictor of use.
A study of 40 cannabis-dependent patients found significant psychiatric symptoms but no changes in thyroid hormones or cardiovascular measures compared to controls, suggesting tolerance to some but not all effects.
A study of 2,335 opioid use disorder patients found that current cannabis use was associated with 41% higher odds of suicidal ideation, adding complexity to the cannabis-for-opioid-harm-reduction narrative.
In a Danish cohort of 1,632 children, early cannabis use by age 15 was the strongest independent predictor of subclinical hypomania at age 16, with a 3-fold increased risk.
Meta-analysis of 8 national surveys finds cannabis use disorder is associated with 3x higher odds of major depression and generalized anxiety disorder.
Survey of 145 Colombian psychiatrists finds strong support for medical cannabis availability but low confidence in legal access knowledge, with most disapproving its use for psychiatric conditions.
Comparative study finds cannabis-induced psychosis and schizophrenia have distinct symptom profiles, with different patterns of speech and thought disorder.
Qualitative study of 50 young SGM men finds cannabis used to manage anxiety during sex, substitute for harder drugs, and self-treat depression, with some experiencing adverse effects.
ABCD study of 11,489 children finds prenatal cannabis exposure associated with greater psychopathology, sleep problems, higher BMI, and lower cognition at ages 9-11.
Study of 730 binge-drinking young adults finds daily cannabis use linked to impulsive reward choice and hyperactive ADHD symptoms, with no effects from occasional use.
Prospective study finds cannabis-using psychosis patients have higher dissociation and worsening functioning over 8 months, while non-users improve.
Study of 71 hospitalized adolescents found that neither alcohol nor cannabis alone predicted daily self-harm, but using both together on the same day increased self-harm odds by over 30-fold.
Study of 370 involuntary psychiatric patients found THC-positive patients were 2.29 times more likely to be readmitted within a year and more likely to be prescribed benzodiazepines at discharge.
Systematic review of 124 studies found cannabis use in healthy people was linked to adverse effects on psychosis risk, cognition, mood, and functioning, driven by THC content, frequency, and age of onset.
Study found adults with ADHD show different clinical profiles based on substance type: cannabis users had worse general psychopathology, while stimulant/alcohol users showed more hyperactivity and legal problems.
Systematic review found only 8 small RCTs testing cannabinoids for depression, anxiety, or PTSD, with insufficient evidence to recommend cannabis for any of these conditions.
Prospective study of 361 veterans found sleep problems drove ADHD-related cannabis use, while using cannabis to cope with negative emotions predicted cannabis-related problems.
Study of 391 first-time justice-involved youth found emotional dysregulation and positive cannabis expectations predicted cannabis initiation, while self-control was protective.
Review of 86 studies found cannabis use in veterans consistently linked to other substance use, psychiatric disorders, and self-harm, with almost no studies testing therapeutic benefits.
Within-person analysis of nearly 8,000 people over 10 years found cannabis use predicted a sevenfold increase in psychotic experiences, but psychotic experiences did not predict cannabis use, supporting a causal direction.
Among 109,308 UK Biobank participants, cannabis use was strongly linked to psychotic experiences, with people in the top fifth of schizophrenia genetic risk showing nearly 10 times the effect size compared to those in the bottom fifth.
Prospective study of 46 adults using real-time smartphone assessments found medical cannabis reduced pain intensity, anxiety, depression, and improved sleep over 3 months.
Study of 517 hospitalized patients with schizophrenia found cannabis use was not independently associated with longer hospital stays or more frequent admissions after adjusting for covariates.
Survey of 1,034 college students found higher cannabis use was associated with more hallucinations (independent of depression) and delusional ideation that was more distressing and held with greater conviction.
Web-based cannabis reduction program reduced use by 11.5 days/month in adults with ADHD symptoms, with significant improvements in depression, anxiety, and ADHD symptom severity at 3 months.
Analysis of 15,238 US adults found starting cannabis before age 15 was associated with 4.4 times higher odds of lifetime suicide attempt and 3.3 times higher odds of suicidal ideation.
Three young men with autism developed mania or psychosis after using CBD/THC products, highlighting potential psychiatric risks of cannabis use in the ASD population.
Study of 167 clozapine-treated schizophrenia patients found cannabis use and trauma were associated with psychotic symptoms but not primary negative symptoms, suggesting distinct pathways.
In first-episode psychosis, cognitive reserve protected against poor outcomes only in non-cannabis users, suggesting cannabis overwhelms the brain's built-in cognitive resilience.
Meta-analysis of 19 studies (5,191 participants) found cannabis users had significantly worse formal thought disorder whether healthy, in first-episode psychosis, or with schizophrenia.
GRADE-based clinical guidelines found no evidence to recommend any specific antipsychotic for schizophrenia patients with cannabis use disorder, highlighting a critical evidence gap.
Study of 215 Israeli combat veterans found moral injury was linked to cannabis use disorder through depression, with social support unexpectedly failing to protect against this pathway.
Among Israeli combat veterans, depression (AOR 1.98) but not PTSD independently predicted cannabis dependence, challenging assumptions about PTSD-driven cannabis use in military populations.
A review of Canada's cannabis legalization finds mixed public health impacts: use increased in some groups, smoking declined, hospitalizations showed mixed results, and impaired driving prevalence was stable.
A one-year study of 339 young adult cannabis users found childhood trauma led to problematic use primarily through using cannabis to cope with distress, while sleep-motivated use was not associated with problems.
A systematic review of 22 cohort studies found no consensus on whether cannabis causes suicidal behavior, though heavier or earlier use may increase risk.
Preclinical evidence for cannabinoids in Parkinson's and Alzheimer's is promising, but older adults are using them off-label despite almost no clinical trial data.
A study of 2,945 young adults found racial/ethnic minorities experienced worse health, academic, and life satisfaction outcomes at the same levels of alcohol and cannabis use as White peers.
Among 539 university students, impulsiveness explained the link between problematic cannabis use and suicidal behavior, while childhood trauma amplified the cannabis-suicide attempt connection.
Longitudinal research links prenatal cannabis exposure to lasting effects on behavior, memory, and substance use from childhood through adulthood.
NHANES data from over 21,000 adults linked past-30-day cannabis use to 54% higher odds of suicidal ideation and 53% higher odds of depression.
Research suggests CBD may work partly by changing DNA methylation patterns, offering a new explanation for its broad effects on anxiety, depression, and psychosis.
A randomized trial found Housing First reduced alcohol and cannabis use among homeless individuals at 21 months, with additional mental health benefits for those with severe mental illness.
Study validated the DSM-5 cannabis use disorder diagnosis and severity levels, with severe CUD showing the strongest associations with psychiatric and social impairment.
Survey of 1,230 veterans found those who co-used tobacco and cannabis had significantly higher stress, PTSD, depression, and anxiety than single-substance users.
Meta-analysis of 20 studies found cannabis use was associated with 2.3x risk of suicide attempt, 2.0x suicidal ideation, and 1.7x suicide planning among youth ages 11-21.
Nationally representative Canadian data showed young adults with ADHD had 46% higher odds of cannabis use disorder and 69% higher odds of any substance use disorder.
Canadian survey during COVID-19 found increased cannabis use was associated with nearly twice the odds of suicidal ideation, alongside social isolation and depression.
82 children with autism who completed 6 months of CBD-rich cannabis showed significant improvements in social communication on both clinical and parent-reported measures.
Meta-analysis of 45 fMRI studies (2,702 youth) found cannabis users showed altered activation in prefrontal and cingulate regions, varying by sex, severity, and psychiatric comorbidity.
Among 422 pediatric ER patients testing positive for cannabis, 71% presented after legalization. Suicidal ideation was the most common complaint at 43%.
Employers face conflicting laws and unreliable drug tests — a practical framework for cannabis workplace policies addresses safety, legal protections, and impairment measurement.
People with ADHD may use cannabis to manage self-regulation deficits, but evidence for therapeutic benefit is limited and the risk of problematic use is elevated.
Among 608 US veterans with PTSD, frequent cannabis users were 3-4x more likely to have depression, anxiety, and suicidal ideation, and 8-12x more likely to rely on avoidance coping.
Standard ASD medications often cause side effects that mimic ASD symptoms. Early evidence suggests CBD-rich cannabis may be effective and better tolerated, but controlled trials are needed.
Among 9,863 US adolescents, racial bullying involvement predicted different substance use patterns by ethnicity, with African American bully-victims more likely to use marijuana.
Analysis of 1,174 young adults found five distinct cannabis use disorder profiles with different patterns of consumption, control, and withdrawal symptoms.
Among 910 young Canadian adults who drive after cannabis use, four distinct profiles emerged, from well-adjusted youth to those with generalized risky behavior and high distress.
Among 4,270 French students, ADHD symptoms predicted continued cannabis use after one year but did not drive new cannabis initiation.
National data from 2011-2017 found marijuana associated with teen suicidal ideation and attempts at rates comparable to tobacco and alcohol, with a dose-response pattern.
In Lebanon, cannabis use disorder nearly tripled the odds of needing intensive psychiatric outreach for psychosis, alongside other severity markers.
Cannabis use was linked to suicidal ideation in 412 youth aged 13-18, but existing school prevention policies did not weaken this association.
Among 5,738 African American male students, disliking school and believing most peers used marijuana were the strongest predictors of past-year use.
Only 16 controlled studies exist for CBD in psychiatric disorders. Most promising evidence for psychosis and anxiety, but not enough for clinical recommendations in any condition.
Young adults with bipolar disorder showed a unique brain response to stress that correlated with less cannabis use and better depression outcomes over one year.
Among 256 pregnant patients, continued cannabis use through delivery was linked to 10% lower birthweight, and mothers with higher childhood trauma scores were more likely to keep using.
Young adults who newly adopted an LGBQ+ identity had 2.9x the risk of starting cannabis use, suggesting identity transition is a vulnerable period.
Following 701 people from age 10 to 22, high social anxiety trajectories predicted adult cannabis use (but not alcohol) along with dramatically elevated mental health disorder risk.
Analysis of an online pregnancy forum found cannabis-using mothers primarily seek information about drug testing, CPS involvement, and state-specific legal consequences rather than health effects.
Brain imaging found adults with childhood ADHD who used cannabis had weaker thalamus-parietal connections than non-users, while non-users had stronger-than-typical connectivity in these regions.
Population survey found adults using both marijuana and e-cigarettes were 12 times more likely to be under 30 and had elevated rates of poor mental health, respiratory conditions, and cigarette smoking.
A 9-year-old with nonverbal autism showed reduced violent outbursts, better sleep, and improved social interactions after starting full-spectrum CBD oil with low-dose THC.
Three young men with ADHD showed measurable improvements in depression, anxiety, emotional regulation, and inattention after adding cannabis, with plasma levels confirming cannabinoid presence.
A digital therapeutic app delivering behavioral therapy and contingency management more than doubled 12-week abstinence rates for alcohol, cannabis, cocaine, and stimulant use disorders compared to treatment-as-usual.
Longitudinal study of 361 veterans found cannabis use predicted worsening PTSD intrusion symptoms at 6 months, while PTSD predicted cannabis use disorder at 12 months, suggesting a harmful cycle.
Focus groups with 16 young psychosis patients found they continued cannabis use not despite knowing risks but because they lacked alternative strategies for socializing, enjoyment, and mood management.
Nationwide Swiss data showed sharp increases in cannabis-related psychiatric hospitalizations from 1998-2020, concentrated in the 15-44 age range.
Among 1,424 adolescents, anxiety/depression predicted cannabis use only in girls with high ADHD hyperactivity-impulsivity, highlighting a specific risk profile for targeted intervention.
Review confirmed gender differences exist in cannabis-related psychosis, depression, and anxiety, but the direction varies. Women may be more vulnerable to mood effects; men may show stronger psychosis links.
JAMA Psychiatry study found bipolar II and cannabis use disorder cluster in families. Mood episodes typically preceded CUD, suggesting shared vulnerability and a potential prevention target.
Adding a self-regulation-focused Grit program to residential substance treatment produced larger reductions in cannabis and methamphetamine use in young adults, sustained at 12 months.
Systematic review of 6 studies found contingency management effectively reduced cannabis use and achieved abstinence periods in people with psychotic disorders or major depression.
Longitudinal study of 1,084 young adults found 27% increased marijuana use during early COVID-19. Childhood adversity predicted increases among those with low resilience.
Two-year study found methamphetamine, but not cannabis, predicted worse cognitive outcomes in first-episode schizophrenia patients.
Study of 254 veterans with bipolar disorder found current cannabis users had better working memory and functioning than past or non-users, but also higher rates of PTSD and suicidal ideation.
Case report of a young adult with cannabis use, COVID history, and other complicating factors who developed severe psychosis but achieved complete recovery.
Systematic review of 9 studies found cannabis products reduced hyperactivity, anxiety, sleep problems, and irritability while improving cognition and social interaction in autism.
Systematic review of 15 studies found cannabis use associated with aggression in PTSD and psychotic disorders, but causal conclusions cannot be drawn due to methodological limitations.
Survey of 1,738 students found those with ADHD reported cannabis helped with hyperactivity, impulsivity, and medication side effects, with frequent use moderating executive dysfunction.
Review found growing evidence for cannabis-based medicine in Tourette syndrome, with two small RCTs showing THC safety and efficacy for tics, though larger trials are ongoing.
Australian registry of 3,961 patients found medicinal cannabis was safe and showed sustained improvements in pain, mental health, and insomnia over 2+ years.
Colorado study found each increase in dispensary density was associated with 24% more psychosis ER visits after recreational legalization, while schizophrenia visits were unchanged.
Study of 1,099 people with psychotic disorders found those with atypical psychosis had early cannabis use rates (17.5%) closer to schizophrenia (11.5%) than psychotic bipolar disorder (5.3%).
Pilot trial of 52 young adults found emotion-focused therapy outperformed standard CBT for reducing emotional distress in cannabis use disorder, with both treatments reducing cannabis use.
Study of 451 Latinx college students found attachment style, marianismo beliefs, and bicultural self-efficacy shaped the link between childhood adversity and substance use among women.
London study of 2,130 catatonic episodes found 5.1% were substance-related, with cannabis the most frequently implicated substance. Cases increased between 2007 and 2016.
Review of 39 studies (12,143 patients) found about 26% of medical cannabis users for chronic pain experience adverse events, but serious harms occur in fewer than 5% of patients.
Longitudinal study of 1,465 young people found cannabis use and suicidal ideation were reciprocally linked from ages 15-20, suggesting they may reinforce each other over time.
Among 23,091 medical cannabis patients in Ontario, cannabis poisoning ER visits occurred at 8 per 10,000 person-years and mental health crises at 15 per 10,000, with prior substance use being the strongest predictor.
Medical cannabis patients in Ontario had 2.45x the risk of drug poisoning ER visits and 2.27x the risk of substance-related mental health ER visits compared to matched controls.
Saskatchewan pandemic survey found suicidal ideation was highest (25.8%) among those with both cannabis and alcohol problems, with younger adults and LGBTQIA2S+ individuals at elevated risk.
Experiment with 700+ participants found that inducing negative mood increased self-reported cannabis problems and negative expectancies, even though actual use did not change.
Among 611 substance use inpatients, cannabis use disorder was the strongest predictor of 3-month relapse (53.3% rate, OR=2.31) in patients with co-occurring psychiatric disorders.
Meta-analysis of 3,053 schizophrenia patients found cannabis use associated with more positive symptoms and excitement but fewer negative symptoms, with no link to depression or disorganization.
Analysis of 14,087 Australians entering drug treatment found cannabis was the primary concern for 15%, with high rates of poor mental health and polysubstance use across all groups.
Real-time tracking of 62 psychiatrically hospitalized teens found cannabis use boosted positive mood and reduced anger, with stronger effects in youth with PTSD or anxiety disorders.
National US data found pregnant and postpartum women with mental health disorders had 2-12 times higher odds of cannabis use disorder, with 9.8% overall cannabis use prevalence.
Australia's ~300,000 medical cannabis approvals showed one-third were for psychiatric conditions, dominated by anxiety disorders, often for conditions with limited clinical evidence.
Lancet Psychiatry study found significant genetic overlap between cannabis use and schizophrenia/bipolar disorder, with evidence of causal effects running in both directions.
Prospective study of 334 people at clinical high risk of psychosis found no association between baseline cannabis use and transition to psychosis over 2 years.
Interrupted time series found no increase in self-harm ED visits or hospitalizations in Ontario or Alberta following Canadian cannabis legalization.
National Jamaican survey found nearly 20% of adolescents used marijuana recently, with loneliness, suicidal ideation, and parental smoking among key correlates.
Analysis of 3,373 pregnant US women found serious psychological distress associated with nearly 3x more cannabis use days and 5x more binge drinking days.
Brazilian survey of 2,637 adults found marijuana's well-being effects shaped by race, gender, and class, with Indigenous peoples and youth most harmed by prohibition.
After one month, 63% of new medical cannabis patients reported effective pain relief, plus reduced medication use, less anxiety, and better sleep — though finding the right product was a common struggle.
A study of nearly 10 million people found ER visits for substance-induced psychosis carried a 163-fold increased risk of later schizophrenia, with cannabis showing the highest transition risk of any substance.
Ontario data showed no increase in cannabis psychosis ER visits after initial legalization, but a 30% jump after retail and product expansion, driven by youth aged 19-24.
A longitudinal study of 1,000+ adults found marijuana use was associated with DNA methylation changes in genes related to schizophrenia, bipolar disorder, cell proliferation, and hormone signaling.
A 30-day experience sampling study of 145 women experiencing intimate partner violence found PTSD externalizing and arousal symptoms linked to same-period cannabis use but not future use.
Children prenatally exposed to both a natural disaster and maternal cannabis use had synergistically elevated psychiatric risk, with a 31-fold increase in behavioral disorders.
Review found strong preclinical evidence for CBD improving cognition, but human studies have not confirmed these effects.
National data showed weekly+ cannabis use was a stronger marker of social anxiety severity and suicide risk than formal cannabis use disorder diagnosis.
15-year Swedish study of 12,143 CUD patients found 23% readmission rate, with schizophrenia (54% higher), low education (40% higher), and ages 18-35 as top risk factors.
A Swedish registry study of 3.3 million people found CUD diagnoses rising in younger cohorts, with 80% psychiatric comorbidity and distinct gender-linked subgroups.
First case report of cannabis-assisted psychotherapy for dissociative PTSD showed dramatic improvement over 10 sessions, drawing parallels to psychedelic-assisted therapy.
Mini-review of 12 studies found suggestive evidence that cannabis use increases suicide risk in schizophrenia, particularly among men and during first-episode psychosis.
Among 62 first-episode psychosis patients, synthetic cannabinoid users showed worse symptoms, slower recovery, and higher aberrant salience than THC users or non-users.
Among 61 first-episode psychosis patients followed for 9 months, synthetic cannabinoid users had worse symptoms, more suicidal ideation, and poorer recovery than THC users or non-users.
Among 352 Colombian adolescents, cannabis and tranquilizer use were independently linked to suicidal behavior alongside depression, aggression, and borderline traits.
Pilot RCT of 17 volunteers found 600mg CBD did not alter ayahuasca's effects on social cognition, with good tolerability and no safety concerns.
Umbrella review of 25 systematic reviews found consistent evidence linking recreational cannabis to suicidal ideation and attempts, with dose-response patterns.
Pilot study found adults with cannabis use disorder had blunted pleasure responses that personalized scripted imagery could partially restore.
Adding EMA to counseling increased mindful awareness in young cannabis users, and higher mindfulness was linked to lower cannabis desire and negative affect.
ABCD Study analysis of ~10,000 children found sleep protects against behavior problems, but prenatal cannabis exposure significantly weakened this protective effect.
EU-GEI study of 1,125 people found those who first used cannabis to cope with negative emotions had higher psychosis risk than those who started for social reasons.
Survey of 415 Canadian military members and veterans at a mental health clinic found cannabis use was common, associated with younger age and PTSD.
Two case reports show adolescent vaping of nicotine and marijuana during COVID linked to social stressors and mental health symptoms, highlighting need for holistic treatment.
Analysis of 265,000+ pregnancies identified four prenatal substance use patterns including a cannabis-predominant group (4.9%) with elevated depression and anxiety.
National survey of 68,000+ US teens found nondisordered cannabis use (10.2%) associated with doubled odds of depression, suicidal ideation, and academic problems vs. non-use.
Prospective study of 56 patients found cannabis-induced psychosis presents with positive symptoms and improves steadily over one month after cannabis cessation.
A 12-week group therapy program combining CBT and motivational enhancement reduced cannabis use, cravings, withdrawal, depression, and anxiety in treatment-seeking patients.
EU-GEI study of 2,112 people found cannabis use partially mediates the relationship between childhood adversity and first-episode psychosis.
Study of 323 cannabis use disorder patients found most had pre-existing adverse childhood experiences, social-emotional impairments, or neurodevelopmental conditions.
Cross-sectional study of 153 substance-dependent patients in North India found ADHD prevalent across substance types including cannabis dependence.
Cross-sectional study finds cannabis use linked to adverse psychosocial functioning among North American college students, extending adolescent findings to ages 18-22.
Review finds cannabis increases psychosis risk, worsens outcomes in vulnerable youth, and recommends integrated treatment approaches for co-occurring use and psychotic symptoms.
Propensity-matched study found medical cannabis authorization associated with increased ED visits and hospitalization for depressive disorders.
Survey of 14,897 Canadian adults found concurrent mental health problems and problematic substance use common during COVID-19, with identifiable risk factors.
Rural Maryland ER data linked cannabis use disorder to 2.7x higher odds of suicidal ideation, though depression and other substance disorders carried stronger associations.
Two-year Brazilian study found cannabis use associated with 75% higher loneliness risk, the largest effect among clinical factors studied, though the direction of causation is unclear.
Review of 24 studies found youth cannabis use linked to depression, psychosis, suicide, and cognitive decline in Australia and the US, with effects worsening with heavier use.
Analysis of 10 million insured patients found cannabis laws were associated with 12-15% fewer benzodiazepine fills but increases in antidepressant and antipsychotic prescriptions, suggesting complex effects on mental health treatment patterns.
Among 741 cannabis users, emotion dysregulation was linked to more problematic use in men but less so in women, suggesting cannabis treatment may need sex-tailored approaches to emotional skill building.
Longitudinal study of 339 young cannabis users found emotional distress coping motives persistently mediated the link between childhood abuse and problematic use into adulthood, while sleep and pain motives were linked to less problematic use.
Meta-analysis of 15 studies found medicinal cannabis had no effect on depression, anxiety, or stress in cancer patients, but increased appetite 12-fold. Higher THC doses doubled the likelihood of anxiety events.
Canadian data from 2020 found residents of health regions with higher COVID-19 rates were more likely to use cannabis and use it more often, even after accounting for pre-pandemic use levels and demographics.
Qualitative interviews with 36 cannabis-using mood/anxiety patients found most continued for symptom relief despite recognizing cognitive dysfunction and worsening mood over time, rarely consulting doctors about their use.
Longitudinal study of 1,105 veterans found a self-reinforcing cycle: insomnia increased stress, stress increased cannabis use, and cannabis use worsened both stress and insomnia, challenging its use as a sleep or stress remedy.
Population study of 910 adults 65+ found 20% had used marijuana and 5% used recently — current users showed more depression, anxiety, and functional impairment.
In a Brazilian community sample, cannabis use was linked to worse disorganization symptoms among people at risk for psychosis but did not predict transition to full psychiatric disorders over 2.5 years.
In a nationally representative study of 5,585 US youths, concurrent tobacco and cannabis use was linked to nearly double the odds of behavioral problems compared to using either substance alone.
A longitudinal study of 850 teens found that affiliation with delinquent peers partially mediated the link between cannabis use and aggression, suggesting social context matters as much as substance use itself.
In a prospective study of 545 young women of color, frequent cannabis use (20+ times monthly) predicted increased depression, delinquency, and school suspension over 6-12 months.
Among 5,281 Americans aged 13-40, co-use of tobacco and cannabis was linked to higher depression rates than either substance alone, with e-cigarettes plus smoked cannabis the most common combination among depressed co-users.
Prospective study of 2,943 trauma survivors found PTSD symptoms predicted increased substance use over time — with prior trauma and demographics determining who was most vulnerable.
Pilot trial of 32 patients found VR avatar therapy reduced cannabis use (d=0.80) with effects lasting 12 months in people with dual CUD and severe mental illness, confirmed by urine testing.
Analysis of 12 years of NSDUH data found cannabis addiction was one of four substance addictions that stably predicted suicidal thoughts, planning, and attempts across all survey years.
Norwegian 13-year longitudinal study of 1,988 youth found within-person cannabis use increases linked to anxiety, depression (males), and suicidal ideation (3.4x in males, 2.5x in females).
Qualitative analysis of an online pro-cannabis pregnancy forum found pregnant people described using cannabis for mental health, nausea, pain, and stress, often as an alternative to prescribed medications.
An RCT found that an app-based parenting program was especially effective at reducing anxiety in parents who started using cannabis regularly during adolescence.
Data from 323,896 US college students (2009-2019) showed the link between cannabis use and mental health problems grew substantially stronger over the decade.
Meta-analysis of 4 RCTs found cannabis users with PTSD still benefited from trauma-focused therapy, but attended fewer sessions and showed less improvement in other substance use.
Analysis of 1,789 urban adolescents identified five distinct substance use patterns, with mental health and perceived drug access differentiating higher from lower risk groups.
Analysis of 4.3-5.7 million VA records (2005-2019) found cannabis use disorder diagnoses rose disproportionately among veterans with psychiatric disorders, especially bipolar and psychotic conditions.
An 8-year study found that light cannabis use in late adolescence was associated with conduct problems but not with cognitive decline or changes in reward-related brain activity.
A scoping review found that cannabis exposure alters DNA methylation at genes tied to dopamine signaling, neurodevelopment, and cell survival, with links to psychiatric symptoms.
A study identified four distinct cannabis user profiles and found that rapidly escalating users tried to quit most often, while long-term heavy users had the worst cessation outcomes.
A German study found rising THC potency was associated with more cannabis-related psychiatric diagnoses across all 16 federal states, with men affected more than women.
College drinkers with ADHD had worse sleep and more alcohol-related consequences, but ADHD did not increase cannabis-related negative outcomes.
A longitudinal study of 7,464 Australian men found cannabis use linked to transitioning from suicidal thoughts to attempts, while alcohol was not.
CBD-dominant cannabis extract improved communication, attention, and behavior while reducing aggression in 30 children with moderate-severe autism.
Evening chronotype and cannabis use disorder independently predicted earlier bipolar mood symptom onset, suggesting circadian rhythm disruption may underlie both conditions.
Adults prenatally exposed to cocaine started cannabis younger, and this earlier onset mediated the path to higher anxiety and more severe cannabis use in adulthood.
Among 360 Swiss cannabis users, depression and ADHD specifically predicted heavier use after controlling for other factors, while anxiety and psychosis associations disappeared.
A 23-year-old with substance use history developed recurrent catatonic episodes after cannabis use, requiring ongoing lorazepam to prevent relapse.
Clinical review finds growing evidence for cannabinoids in autism, Tourette syndrome, anxiety, and PTSD, with practical dosing: start 1-2.5 mg THC/day, target 10-20 mg.
UK registry data from 141 MS patients found prescribed cannabis products improved quality of life across cognitive, physical, emotional, and social domains over six months.
Among 12 million Ontarians, cannabis-related ER visits were linked to nearly 4x higher risk of anxiety disorder within three years, with young males at highest risk.
Cannabis-involved self-harm ER visits increased 90% over 12 years in Ontario after medical liberalization, while alcohol-involved self-harm declined.
Study of 104 psychotic disorder patients in Greenland found 68% had harmful cannabis use and 80%+ smoked daily.
Review of 170 articles maps CBD's neuroprotective mechanisms across brain disorders.
Review finds CBD shows promise for autism through endocannabinoid system interaction, gut-brain modulation, and a favorable safety profile, though evidence is still preliminary.
Cannabis use among 187 forensic psychiatric patients rose after Canadian legalization, with over half showing mental health decline after use, though violence rates did not increase.
Higher mindfulness skills in Argentine college students were linked to less cannabis use through reduced emotional distress and lower coping-based use motives.
Five-year study found heavy cannabis users with disrupted cortisol stress responses had 3.2x higher odds of suicidal thoughts and behaviors.
Daily cannabis use at age 24 was linked to elevated suPAR, a novel chronic inflammation marker, while less frequent use and traditional inflammatory markers showed no association.
Cannabis use disorder worsens PTSD through psychological inflexibility — rigid, avoidant thinking that prevents trauma processing — a mechanism that's treatable with targeted therapy.
Swedish mixed-methods study found that cannabis, alcohol, and gambling users largely share the same barriers to treatment: privacy concerns, stigma, and poor availability.
ABCD study of 10,092 early adolescents found multiple dimensions of gender diversity associated with higher odds of cannabis experimentation at ages 12-13.
Study of 616 untreated substance users found cannabis use was not associated with suicidal thoughts, while methamphetamine and heroin use were strong independent predictors of suicidality.
Analysis of 5,194 young adults found 1.1% had both cannabis use and social anxiety, strongly associated with other psychiatric disorders including panic disorder (OR up to 19.05).
Canadian survey of 13,527 cannabis users found that after legalization, only people with schizophrenia showed significant increases in daily use (9-fold higher odds), while other psychiatric groups showed no change.
Systematic review of 78 studies found cannabis use associated with increased depressive and manic symptoms, higher risk of developing mood disorders, and worse treatment outcomes.
In 183 veterans treated for PTSD + substance use, ongoing cannabis use didn't predict worse PTSD symptoms or dropout at subsequent assessments — though concurrent heavy drinking was associated with worse symptoms.
Study of 470 psychiatrically hospitalized adolescents found cannabis vaping as the primary use method associated with 2.4x higher odds of recent suicide attempt.
French ER study found nearly 1 in 4 young visitors (16-25) were using cannabis, with strong associations to unemployment, sexual abuse history, and alcohol problems.
RCT of 1,489 university students found the Minder app significantly reduced anxiety, depression, and cannabis use frequency over 30 days, with 77% engagement.
Systematic review found only 5 RCTs on integrated treatment for psychiatric disorders in cannabis-using youth, revealing a critical gap for depression, bipolar, anxiety, and PTSD.
National study of 113,000 young adults found daily cannabis use associated with 1.7-1.8x violent behavior in males, while any cannabis use was linked to 1.6-2.4x higher odds in females.
PET imaging shows cannabis users with trauma have 15-20% higher mGlu5 glutamate receptors in frontal and limbic brain regions — a molecular link between the endocannabinoid and glutamate systems.
Interviews with 20 psychiatric hospital staff found cannabis legalization improved some aspects of care but increased use, complicated mental health treatment, and exposed gaps in provider training.
Among 299,496 pregnancies, psychiatric disorders increased prenatal cannabis use 1.6-2.8x and substance use disorders increased it 4-22x, suggesting widespread self-medication during pregnancy.
Baseline data from 79 Australian youth found those with substance use disorders had worse depression, anxiety, and more frequent cannabis use than substance-using peers without a disorder.
Analysis of YRBS data found cannabis legalization design matters for youth mental health: permissive and pharmaceutical bundles improved outcomes while fiscal focus worsened them.
Study of 1,476 Black adults with criminal justice contact found marijuana use linked to family stress and sleep problems in men, neighborhood stressors in women.
Case of a 26-year-old with autism who developed obsessive cannabis use and severe food restriction, requiring integrated multidisciplinary inpatient treatment.
ABCD Study found SGM youth had higher future marijuana use and past suicide attempts, but family conflict, discrimination, and trauma did not explain the disparity.
ABCD Study found childhood depression, hopelessness, and suicide attempts before age 10 predicted marijuana initiation by age 15, independent of socioeconomic factors.
Longitudinal study of 526 medical cannabis patients found severe anxiety (21% of patients) did not improve over 12 months, while minimal and moderate anxiety showed slight but not clinically meaningful decreases.
Case report of a 31-year-old with no psychiatric history who developed a manic episode after three months of escalating high-dose CBD vaping, resolving after discontinuation.
Genetic risk scores for cannabis use disorder predicted schizophrenia even in people without documented cannabis use, suggesting shared genetic pathways between the two conditions.
Nationally representative survey of US high school students found higher adverse childhood experience scores significantly predicted more frequent cannabis use.
Review of prenatal cannabis exposure research found consistent links to higher ADHD risk in children, while effects on cognition, autism, and learning remained inconclusive.
Survey of 3,159 Asian Americans during COVID-19 found racial discrimination was specifically linked to cannabis use for coping, while general pandemic stress drove alcohol and tobacco use.
Seven years after legalization, Canada's cannabis surveillance still uses outdated diagnostic frameworks, excludes key populations, and can't reliably measure whether legalization has increased or decreased harms.
First randomized trial of legal vs illegal cannabis found a trend toward reduced misuse with regulated access, with benefits concentrated among polysubstance users.
Study of 588 methadone patients found psychiatric comorbidity was associated only with increased cannabis use, not opioid, cocaine, or alcohol use.
Longitudinal study of rural reservation-based youth found 12th-grade cannabis use predicted 21-24% increased loneliness risk six months after high school.
Application of Bradford Hill causation criteria to longitudinal studies found substantial evidence that adolescent cannabis use may precipitate bipolar disorder in vulnerable individuals.
300 mg CBD increased feelings of calm and relaxation before a 2-mile run but had no effect on running speed, heart rate, or other performance measures in 12 runners.
Cannabis use was significantly linked to depression and anxiety among sexual and gender minority young adults, highlighting the need for targeted interventions in this population.
Meta-analysis of 13 studies found converging experimental and observational evidence that cannabis use causes paranoid symptoms, with THC-dominant products producing the strongest effects.
Latent class analysis of 4,031 young adults found moderate oil/concentrate users had the worst outcomes across problematic use, mental health, and impaired driving measures.
Survey of 1,833 Ugandan secondary school students found 2.6% marijuana use, with male sex (2.2x odds) and mental illness history (2.9x odds) as the strongest predictors.
19 U.S. states list Alzheimer's as a medical cannabis qualifying condition, but <1% of certifications are for AD, and clinical evidence supporting cannabis for dementia agitation is sparse.
Large European case-control study found cannabis-associated psychosis risk declined after quitting and returned to never-user levels after about 37 weeks, though heavy high-potency users may retain elevated risk longer.
Interviews with 13 pregnant sexual minority young people found cannabis use was driven by stress and mental health, with pregnancy motivating reduction attempts but some struggling to quit.
Study of 115 college cannabis users found imposter syndrome was linked to more cannabis problems through a pathway of social anxiety leading to coping-motivated use.
Study of 254 Black American cigarette smokers found racism-related emotional distress (but not general anxiety or depression) was linked to cannabis problems, partly through increased cannabis consumption.
Prospective study of 4,380 children found maternal cannabis use before (not during) pregnancy predicted higher autism symptoms across childhood, while continued tobacco use during pregnancy predicted autism symptoms at age 6.
Longitudinal study of 6,811 Army veterans found cannabis use and other substance use predicted subsequent suicidal ideation and planning, with interactions by sex and depression status.
Nationally representative longitudinal study found COVID stay-at-home orders doubled depression odds, but worsening mental health was associated with less marijuana use (78% reduction), contradicting the self-medication hypothesis.
Pilot study found young adults reported better mood and less anxiety while high, but showed no changes on implicit or explicit emotion regulation tasks.
BRFSS analysis found ACEs predicted cannabis use overall, but the link to medical cannabis specifically was fully explained by disability and poor health from childhood adversity.
California spatiotemporal analysis found no link between recreational cannabis outlets and self-harm injuries, while alcohol outlet density was strongly associated with nonfatal self-harm.
32-year analysis found cannabis use declined among most US adolescents but not among those with suicidal thoughts or attempts, with female suicide attempters showing a persistent plateau.
Cancer patients had lower baseline endocannabinoid levels, but 30 minutes of moderate exercise boosted endocannabinoids in both cancer patients and healthy controls — along with increased happiness.
Cannabis users with more positive health expectancies experienced greater acute reductions in tension and pain, suggesting beliefs about cannabis shape therapeutic outcomes alongside pharmacology.
Montreal study found the cannabis-nicotine combination had the worst association with anxiety and positive mental health among young adults, while substance count showed no dose-response.
Pilot RCT found vortioxetine improved clinician-rated mood in cannabis users over 6 months but did not reduce cannabis dependence or self-reported mood symptoms.
Among 7,178 cannabis users, dual-use (vaping + smoking) was linked to severe externalizing symptoms, while vaping-only was more common among White, higher-income adults.
Survey found 33% of people with hair-pulling or skin-picking disorders used cannabis in the past year, and users had more frequent symptoms and greater distress.
Cross-sectional study of 82 methadone patients found childhood trauma correlated with greater pain, more alcohol use, and earlier cannabis initiation.
In a zebrafish autism model, CBD reversed hyperactivity and aggression more effectively than risperidone and normalized underlying neurobiological markers.
Open-label study: CBD-rich cannabis for autistic children reduced family accommodation burden and parental distress at 3 and 6 months.
65 autistic children on CBD-rich cannabis for 6 months: reduced anxiety and repetitive behaviors. Anxiety reduction predicted subsequent behavior improvement.
3-month daily diary study of 74 veterans: cannabis use predicted lower next-day stress, which predicted fewer PTSD symptoms and better sleep quality.
Veterans daily diary: cannabis linked to same-day lower stress and better sleep with no next-day effects. Poor sleep drives next-day stress and alcohol use.
Among 104 chronic pain patients on long-term opioid therapy, weaker emotion regulation ability predicted more frequent cannabis use, while pain severity did not, suggesting emotional factors may drive cannabis use more than pain itself.
A systematic review of 49 controlled studies across 11 mental health diagnoses found CBD may offer short-term anxiety relief and CBD/THC combinations helped with cannabis withdrawal and sleep, but THC worsened psychosis and no long-lasting benefits were found for any product.
A study of over 2 million pregnant patients found cannabis use associated with 2.7x higher depression, 5.5x higher panic disorder, 10.7x higher suicidal ideation, and 13.6x higher alcohol abuse, though confounding by underlying risk factors is likely.
In 6.4 million diabetes patients, GLP-1 drugs were linked to 37% lower suicide risk, but this benefit disappeared entirely in patients with cannabis use disorder, who faced 5.5x higher risk regardless of medication.
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.
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.
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 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.
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.
An Ontario population study found cannabis-related hospital visits were associated with 5.4x higher self-harm risk and 9.2x higher suicide risk over 3 years, even in those without pre-existing mental health conditions.
Protocol for a 200-teen RCT testing whether 8 weeks of cannabis abstinence reduces depression and suicidal ideation — using 8 daily phone surveys to capture the moment-by-moment relationship.
Brazilian LGBTQ+ youth, especially those assigned female at birth, had nearly double the odds of cannabis use and started using substances earlier than heterosexual cisgender peers.
Qualitative study found medical cannabis helped parents manage symptoms and be more patient, but stigma and legal fears created tension in their parenting identity.
Males with a specific MAOA gene variant who experienced childhood sexual abuse were more likely to use cannabis for coping, but this combination was associated with lower aggression.
Depression was associated with 30% higher odds of frequent cannabis use among Black college students.
Black college students who started marijuana before 14 were 3x more likely to report suicidal ideation.
Adolescents with incarcerated family members had significantly higher odds of early and current cannabis, alcohol, and nicotine use.
Projection: German legalization may produce 19x more health harm from increased use disorder than gains from reduced contamination.
Cancer survivors with four or more adverse childhood experiences had four times the odds of cannabis use, pointing to early trauma as a key factor in substance use patterns during survivorship.
Two independent samples confirm cannabis use disorder exists on a continuum of severity rather than as a binary condition, supporting the DSM-5 dimensional model.
In nearly 3,000 trauma survivors, household income modified the relationship between PTSD symptoms and substance use, influencing whether people turned to tobacco, alcohol, or cannabis.
Stress eliminated a form of synaptic plasticity in the brain's insular-to-reward pathway in male rats only, dependent on the endocannabinoid system.
Rasch psychometric analysis of DSM-5 cannabis use disorder in 249 inpatients supports the diagnosis as coherent, though the hazardous use criterion does not fit well.
Parents of youth who used cannabis described it triggering or worsening severe mental health crises, while frequently encountering healthcare providers who minimized cannabis-related risks.
A teen's nausea and vomiting were blamed on cannabis use and eating disorder — but her seizures the next day revealed acute intermittent porphyria, a rare treatable condition nearly missed due to diagnostic anchoring.
Childhood adversity increased cannabis use disorder risk across all racial groups, but the effect was strongest among Asian/Pacific Islander respondents and interacted with age of onset in race-specific ways.
Youth in early psychosis programs described cannabis as creating family tension around psychosis risk while some family members' own use created contradictory messages and even bonding opportunities.
Anorexia nervosa involves coordinated epigenetic suppression of the endocannabinoid system: reduced cannabinoid receptors and increased endocannabinoid degradation simultaneously impair appetite signaling.
Cannabis involvement among mass shooters doubled after medical legalization began in 1996, while remaining stable among non-firearm mass murderers, though causation cannot be established.
Cannabis and tobacco use at any frequency signaled elevated social hardship in 77,000 healthcare users, while binge drinking showed this pattern only at daily frequency.
In college students with elevated worry, fear of anxiety symptoms (anxiety sensitivity) predicted cannabis use and coping motives, while intolerance of uncertainty did not.
Psychedelic experiences produced both more positive and more negative effects than cannabis in demographically representative samples, revealing a wider risk-benefit spectrum rather than simply higher risk.
Tracked 2,762 college students over a year and found anxiety predicted later hazardous cannabis use, with impulsivity traits amplifying the connection.
Survey of 82,933 Minnesota students found bias-based bullying was associated with 50-68% higher regular cannabis use among youth with minoritized identities.
Analysis of 16 years of national data found CUD treatment rates declined while barriers like cost, awareness, and stigma grew.
National survey of 94,225 women found 6.8% of pregnant women used cannabis, with first-trimester rates reaching 10-14%, mostly by smoking.
National survey of 10,361 adolescents found bisexual youth had 85% higher odds of marijuana use than heterosexual peers, with disparities varying by age and sex.
Study of 1,098 veterans found cannabis use alone was not linked to suicide risk, but combining it with hazardous drinking produced the highest risk for suicidal behavior.
Analysis of 52,679 US adolescents found COVID-19 widened substance use disparities, with multiply-victimized youth reaching 3.5x higher marijuana use odds during the pandemic.
Prospective study of 16 children with severe autism found CBD-rich extract reduced internalizing behaviors after three months, with caregivers also reporting improved mental health.
Pilot trial of 50 adults found mindfulness-based therapy (MORE) significantly reduced cannabis and cocaine cravings in people being treated for alcohol problems.
A new brief therapy combining trauma writing with cannabis coping skills showed early promise in three young women after sexual assault—but needs rigorous testing.
Two-year study of 961 emerging adults found negative cannabis consequences predicted later depression more than depression predicted cannabis use, especially in women.
Survey of 84 youth in mood disorder treatment and 66 parents found most believe cannabis and CBD effectively treat mental health conditions.
Analysis of 4+ million VHA patients over 18 years found cannabis legalization drove greater CUD increases among veterans with psychiatric disorders than those without.
National surveys found cannabis use disorder increased 1.4 points more among adults with psychiatric disorders between 2001 and 2013, confirming VA findings.
Pilot study of 18 CHS patients found high pain severity, elevated anxiety, extensive prior imaging workups, and a 17% 30-day ER return rate.
Survey of 367 college students found monthly simultaneous cannabis and alcohol use predicted depression in both sexes, with possible male-specific links to anxiety and stress.
Large study of 59,529 minority young adults found racial trauma undermined the mental health benefits of psychological well-being, with distinct patterns for multi-ethnic versus mono-ethnic individuals.
Teen cannabis use has held steady despite legalization, but ER visits, child ingestions, and product potency have all increased—changing the risk landscape.
Study of 2,207 young adults found different types of adverse childhood experiences predicted different substance use patterns depending on racial/ethnic background.
Large study of 92,757 college students found OCD conditions independently associated with higher tobacco, cannabis, and alcohol use risk, plus more than doubled disordered eating risk.
Study of 1,335 psychiatric inpatients found low conscientiousness, low agreeableness, and high openness to experience associated with cannabis use disorder.
Longitudinal study using both self-report and hair THC analysis found cannabis use at 20 predicted increased psychotic-like experiences, worse mental health, and poorer functioning at 24.
Study of 400 young adults found rural participants had lower subjective social status, with a mediation pathway through emotion dysregulation to hazardous cannabis use.
National survey found cannabis use disorder nearly quadrupled suicidal ideation risk in women veterans, while lifetime cannabis use doubled suicide plan odds.
Most young vapers want help quitting, but there's no consensus on how—and 40% also vape cannabis, which they see as less harmful than nicotine.
A 10-year study of 320 first-episode psychosis patients found that most immune markers only predicted outcomes in cannabis users, suggesting inflammation and cannabis interact in shaping psychosis trajectories.
A two-week self-guided online intervention helped 69% of cannabis users meet reduction goals, vs. 49% in the control group.
A meta-analysis of 47 longitudinal studies identified cannabis use as a novel risk factor for violence in psychosis (OR=3.34), comparable to criminal history (OR=3.50).
A systematic review of 42 studies found high-potency cannabis may be linked to problem use, but evidence was "very low" certainty across all health domains examined.
A 10-year study of 3,299 people with HIV found 26% were consistently high cannabis users, associated with depression, tobacco use, and older age.
In 6,049 participants from the ALSPAC cohort, childhood externalizing disorders at age 10 predicted multiple problematic cannabis use trajectories from ages 15-24.
Year-long interviews with people on opioid addiction treatment found they reported less pain, better mood and sleep, and fewer drug cravings from medical cannabis, though cost and appetite changes were concerns.
An Australian national survey found 6.2% of cannabis users met criteria for high-risk use, with daily consumption, starting before age 15, and psychological distress as the strongest predictors.
A longitudinal study of 4,769 US teens found that those spending 30 minutes to 3 hours daily on social media had the highest odds of later marijuana and alcohol use.
The 2023 National Youth Tobacco Survey found home smoking exposure was the strongest predictor of teen tobacco and cannabis use, while mental stress was key for LGBTQ+ middle schoolers.
Analysis of nearly 69,000 suicide deaths found that more permissive cannabis policies and cannabis involvement were both linked to higher odds of opioid involvement in these deaths.
A study of 157 young people in opioid addiction treatment found cannabis use disorder predicted shorter retention, while depression and PTSD were linked to staying in treatment longer.
A Nature Reviews Neuroscience review mapped how the brain's endocannabinoid system regulates anxiety and stress through specific neural circuits, suggesting endocannabinoid-boosting drugs as future treatments.
A randomized trial of 66 adults found that a brief (~16-day) mindfulness program did not reduce cannabis use, cravings, or quantity compared to relaxation or monitoring alone.
A survey of 46 budtenders found most viewed cannabis as beneficial for mental health, especially for sleep and depression, but their perceptions often did not align with scientific evidence.
National Medicaid data showed substance use disorder prevalence quadrupled among autistic adults from 2012 to 2016, with cannabis disorders particularly elevated in those aged 30-64.
A JAMA Network Open trial found a two-session personality-targeted intervention reduced cannabis use escalation by 25% over 4 years in at-risk teens, with similar effects for alcohol and tobacco.
A study of nearly 3,800 medical cannabis patients found 25% had suicidal thoughts at treatment entry, with rates declining over 12 months, though the observational design limits causal conclusions.
A genetic study found social isolation causally increases cannabis use disorder risk by over 4-fold, with depression acting as a key mediator explaining about 22% of the effect.
A meta-analysis of 25 studies found cannabis use linked to suicidal thoughts (46-78% higher odds) and attempts (117% higher in teens) even after accounting for depression, though depression partly explains the connection.
Among 13,477 ED patients with substance diagnoses, cannabis-related conditions were linked to 21% higher overdose odds, with Black, Hispanic, and publicly insured patients at disproportionate risk.
A 16-year study of 52,000+ psychiatric admissions found cannabis users were more likely to need intensive care during the 3-5 day cannabis withdrawal window, especially women and older adults.
Meta-analysis of 120 studies found recreational cannabis use was linked to worse sleep in observational research, but experimental studies showed no effect, suggesting the relationship is more complex than it appears.
Review proposes that cannabinoids interact with extracellular vesicles to create a signaling network relevant to neuropsychiatric disorders, with potential for biomarker-guided personalized treatment.
Randomized study found CBD reduced depression, anxiety, and stress more than THC over 4 weeks in underrepresented groups, with perceived discrimination amplifying the benefit.
Study of 148 people with cannabis use disorder found women used cannabis more in negative emotional contexts than men, with childhood stress linking to coping-motivated use in both genders.
Quebec birth cohort found teens who started cannabis early and used frequently had 51% more mental health visits and 86% more physical health visits by age 23 compared to nonusers.
Study of 257 women found cannabis use during pregnancy independently predicted higher postpartum PTSD and depression, separate from the effects of intimate partner violence.
Survey of 544 SUD treatment patients found cannabis use linked to more trauma and psychiatric diagnoses, but trauma may explain the cannabis-mental health connection.
Youth ages 15-20 built a systems model identifying 14 feedback loops showing how romantic relationship stress and cannabis use reinforce each other.
Japanese national survey found cannabis patients were younger with less severe disorders than methamphetamine patients, but less connected to recovery support services.
Review examines the cannabis-ADHD connection, finding elevated cannabis use risk in ADHD and early evidence that CBD may have therapeutic potential through dopamine pathway modulation.
Study finds a link between more frequent cannabis use and greater gambling involvement, suggesting shared risk factors.
Lancet review catalogs adverse public health effects of cannabis legalization including more ER visits, impaired driving, and pediatric exposures.
Interviews with 20 young adults at psychosis risk reveal coping motives and social pressure as top barriers to cutting back on cannabis, informing mobile intervention design.
National survey of nearly 95,000 adults finds daily cannabis use associated with 145% higher cognitive difficulty in those with chronic conditions and 183% higher in those without.
Mental health clinicians identify nausea as the top driver of prenatal cannabis use, with patients relying on peers for information more than healthcare providers.
Among 973 people with HIV, anxiety and tobacco use were the strongest predictors of higher-risk cannabis use, with over a third screening positive for cannabis use disorder risk.
Clinicians across four specialties identify risk minimization by both teens and parents as the top barrier to treating adolescent cannabis use.
Study reveals two distinct pathways from ADHD to cannabis problems: inattention directly causes functional impairment, while hyperactivity drives heavier consumption leading to dependence.
Surprising finding: regular cannabis use in bipolar disorder was linked to decision-making and functioning on par with healthy non-users, while cannabis impaired healthy participants.
A review of 55 studies found drug legalization and decriminalization had mostly neutral effects on population-level mental health outcomes including depression, anxiety, and psychosis.
Review finds South African medical students hold diverse views on cannabis decriminalization, with gaps in knowledge about health impacts and professional implications.
National survey finds 21% of Black and Hispanic men over 40 with chronic conditions use cannabis, driven by pain, stress, and disease burden.
Daily diary study of 40 women finds cannabis use peaks premenstrually, with mood and pain/coping motives interacting differently across menstrual cycle phases.
Among 540 older adults across the dementia spectrum, moderate cannabis use was not associated with worse cognitive test performance—though problem use may differ.
Meta-analysis of 29 studies finds cannabis use in schizophrenia linked to 40% higher suicide attempt odds and 21% higher suicide death risk.
Two-year study finds 40% of cannabis-using chronic pain patients at high CUD risk with worse mental health, but pain outcomes do not worsen compared to non-users.
A narrative review of cannabis effects across the lifespan found that prenatal and adolescent exposure carries the highest neurological risk, while cannabis use among older adults is rising fastest with the least risk awareness.
An Ontario study of 11.6 million people found that individuals hospitalized for cannabis use disorder were nearly 3 times more likely to die within 5 years, with especially high risks for suicide and trauma.
An Ontario study of 13.6 million people found the share of schizophrenia cases linked to cannabis use disorder nearly tripled from 3.7% to 10.3% during a period of cannabis policy liberalization, reaching 18.9% among young men.
An Ontario study of 6.1 million adults over 45 found that those with emergency visits for cannabis use had 1.72x higher dementia risk than the general population, though lower risk than those with alcohol-related visits.
An ABCD Study analysis of nearly 10,000 children found that prenatal exposure to both cannabis and tobacco was linked to more externalizing behavior problems at ages 9-11 than exposure to either substance alone.
An ABCD Study analysis of 7,691 adolescents found that more social media time at age 12 predicted cannabis experimentation by age 14, with beliefs about cannabis effects mediating about a third of the relationship.
An ABCD Study of nearly 10,000 adolescents found that cyberbullying victims were 4.65 times more likely to try cannabis within the next year, alongside increased risks for depression and suicidal behavior.
An ABCD Study of 8,006 early teens found that social media, texting, and video chatting were linked to cannabis and other substance experimentation one year later, while TV, video games, and passive screen use were not.
Sixteen Iranian psychiatrists identified reduced stigma and patient empowerment as potential benefits of demedicalization of cannabis use disorder, while warning of treatment challenges and normalization risks.
Chronic CBD from weaning reversed anxiety, brain molecular changes, gut microbiota dysbiosis, and increased alcohol motivation in mice with fetal alcohol exposure, with effects varying by sex.
A study of 93,743 US adults found that cannabis use mediated a larger share of the link between depression, pain, and suicidal behavior in women than in men.
A study of 152,930 US adults found that using cannabis and opioids together was associated with a smaller-than-expected increase in suicidal behaviors, particularly in women.
Recreational marijuana laws were linked to an increase of 0.68 suicide deaths per 100,000 overall, but early-adopting states saw decreases while later-adopting states drove the increase.
Interviews with 20 young adults found stronger motivation to quit nicotine vaping than cannabis vaping, with addiction, mental health coping, and identity as key barriers, and health concerns as the main facilitator.
A study of 153 teens with mood symptoms found that cannabis users reported worse anticipatory anhedonia, with more frequent use linked to greater difficulty looking forward to pleasurable experiences.
A scoping review of 99 neuroimaging studies found that 85% detected differences in brain structure, function, or chemistry in cannabis users aged 14-25, though research quality was generally low.
Among 1,466 cannabis users with chronic conditions during COVID-19, 91% used cannabis medicinally for sleep, pain, and headaches, but most lacked medical guidance.
A study of 303,178 California pregnancies found that past-year violence and unsafe living situations were linked to higher cannabis use during early pregnancy, with 7.2% of pregnancies involving cannabis use.
A study of 167,504 teens found five substance use patterns, including a cannabis-centered class, and all groups had higher rates of depression, suicidal ideation, and violence than non-using peers.
Among 530 psychiatric inpatients, cannabis use was linked to lower suicidal intensity in women but not men, with low psychological flexibility amplifying risk in male cannabis users.
A 3-year study of 279 bipolar patients found cannabis linked to earlier onset and more psychotic symptoms but not more hospital readmissions, while tobacco predicted higher relapse rates.
A mouse study found prenatal THC combined with maternal stress caused additive harm to maternal behavior and offspring brain development, with sex-specific effects on anxiety, motivation, and gene expression.
An ABCD Study analysis of 11,858 adolescents found psychosis symptoms were already rising before cannabis initiation, supporting self-medication and shared vulnerability models alongside any direct contributing risk.
Twin study of 3,165 adults found cannabis use for sleep linked to worse sleep quality and more substance use, even after controlling for shared genetics.
Randomized trial of 29 autistic children found CBD oil did not improve social responsiveness but significantly reduced anxiety and parental stress.
Italian 10-year study found people with cannabis use disorder had 22 times the suicide attempt rate of the general population, highest among women and those with co-occurring psychiatric diagnoses.
Study of 471 college students found eating disorder symptoms linked to cannabis use disorder, with male students showing the strongest association.
Small trial of mindfulness-based therapy for cannabis users showed better adherence and trends toward more durable reduction, but differences did not reach statistical significance.
Study of 2,303 diverse young adults found race- and gender-based discrimination linked to worse cannabis use outcomes but fewer alcohol problems.
Small RCT found CBD 300 mg/day significantly reduced behavioral symptoms of vascular dementia after 4 weeks without cognitive or functional side effects.
Daily tracking of 65 young adults found social/environmental triggers drove cannabis use more than emotional states, challenging self-medication theories.
Culturally adapted prevention program improved emotional skills and shifted cannabis habits among Polynesian adolescents, with strongest effects in non-users and low-users.
Large prospective study found ongoing cannabis use beyond the first trimester was linked to 60% higher odds of depressive symptoms later in pregnancy, while any-use overall was not significant.
Across 25 African countries, 3.4% of school-going adolescents used marijuana, with bullying, school skipping, and sadness consistently predicting substance use regardless of substance type.
Study of 105 adolescent psychiatric patients found that distorted time perspective mediated the link between trauma and PTSD severity, with PTSD symptoms in turn predicting cannabis use.
A rigorous review of 8 studies found THC linked to increased psychosis risk while CBD showed potential therapeutic effects—the two cannabinoids may work in opposite directions.
Among 4,407 young adults, loneliness predicted 20% higher cannabis use disorder risk and more frequent cannabis use, independent of depression and other risk factors.
Review of 22 studies found daily high-potency cannabis tripled dissociation risk in first-episode psychosis, with worse functional outcomes, though 75% improved after stopping cannabis.
Review of 62 studies found childhood trauma plus cannabis use amplified psychosis risk up to 31-fold, with earlier onset and worse outcomes than either factor alone.
Review of 50 studies found cannabis nearly tripled suicide risk in first-episode psychosis patients, with dose-dependent effects and identified high-risk intervention windows.
Patients who continued cannabis after first psychotic episode had dramatically worse depression, 3x higher relapse rates, persistent suicidality, and no functional improvement over 9 months.
Systematic review of 38 studies finds high-potency cannabis, genetic predisposition, and environmental stressors interact to drive psychotic-like experiences in otherwise healthy people, with evidence of a bidirectional relationship.
Combining low-dose CBD with resveratrol or alpha-lipoic acid matched high-dose CBD for reducing aggression and depression in PTSD-model mice, though anxiety was unaffected.
Rigorous RCT found 12 weeks of high-intensity exercise did not improve brain structure or mental health in cannabis use disorder, though 80% of participants completed the program and exercise reduced cravings.
Analysis of 1,599 Black male college students found recent marijuana use associated with 77% higher odds of moderately severe to severe depression, compounded by financial stress and racial discrimination.
Systematic review of 11 RCTs finds very limited and low-certainty evidence for cannabis derivatives in autism, with only one trial showing potential benefit for global symptoms.
Annals of Internal Medicine review of 99 studies (221K participants) finds high-THC cannabis consistently associated with psychosis and addiction, with mixed results for anxiety and depression depending on therapeutic context.
Systematic review of 57 studies found that 70% of the highest-quality research reported improvements in anxiety disorders with medicinal cannabis, though reporting standards remain a major issue.
Survey of 6,600+ people with eating disorders found cannabis and psychedelics rated highest for symptom relief, while most prescription antidepressants were rated ineffective for ED symptoms.
Study of 573 psychosis cases found genetic and environmental risks (including cannabis) act independently, with schizophrenia-spectrum disorders driven more by genetics and affective psychosis by environment.
Longitudinal study found childhood trauma predicts cannabis use in new mothers, with resilience protective at low-to-moderate trauma but losing its effect at high trauma levels.
Retrospective survey of 152 cannabis users found significant psychedelic experiences associated with reduced cannabis use, with 'mystical' quality predicting greater reductions.
Narrative review proposes the endocannabinoid system as a unifying mechanism behind diverse treatments for treatment-resistant depression, from brain stimulation to psychedelics.
Large Danish survey found medical cannabis users had lower quality of life (0.44) than non-users (0.74) with the same conditions, likely reflecting that sicker patients are more likely to try cannabis.
Pre-legalization German survey found nearly a third of regular cannabis users experienced external stigma, with medical users and those with use disorder most affected.
Review explains why cannabis-mental health findings seem contradictory: it depends on THC vs CBD content, use frequency, age, genetics, and other often-overlooked factors.
Cannabis users under the influence showed impaired emotion recognition (especially for positive stimuli) but maintained emotional empathy, with specifically dampened reactions to negative stimuli.
A 21-year-old with prior cannabis psychosis developed catatonia after resuming use, triggering rhabdomyolysis, kidney injury, and autonomic instability.
A study of 1,037 adults in Greenlandic substance use treatment found that among women, parental cannabis abuse and physical abuse were linked to high cannabis use, while no specific ACE-substance associations emerged for men.
A review of the two-hit hypothesis of schizophrenia found that animal studies do not consistently show adolescent cannabis worsening outcomes after prenatal immune activation, complicating the expected risk narrative.
Among 7,332 adolescents in the ABCD study, witnessing violence was consistently linked to stronger positive expectations about cannabis, regardless of race/ethnicity, with advantaged neighborhoods providing only modest buffering.
Longitudinal study of 715 Dutch adolescents found childhood trauma predicted earlier and faster-escalating cannabis use from age 16 to 22, but stress physiology differences did not explain the connection.
Study of 80,018 Colombian students found marijuana use was associated with higher aggression, but polydrug involvement and the order of drug initiation were stronger predictors, complicating simple causal narratives.
NLP analysis of 13,025 adolescent health records found mood instability predicted cannabis use in both ADHD (61% higher odds) and depression (38% higher odds), with the association stronger in ADHD.
Study of 9,869 sexual minority patients found bisexual individuals had significantly higher cannabis use, CUD risk, and mental health diagnoses than gay/lesbian patients, with bisexual males particularly affected.
Cannabichromene at 20 mg/kg reduced depression-like behavior in chronically stressed mice comparably to imipramine, likely through CB2 receptor binding and MAO-A inhibition, without psychoactive effects.
National case-control study found cannabis use associated with 83% increased odds of suicide death, independent of alcohol. Used toxicology-verified data from suicide decedents and population controls.
Large prospective study of 2,449 trauma survivors found pre-trauma insomnia predicted heavier cannabis and alcohol use 8 weeks later, partly through early PTSD symptoms.
Systematic review of 50 studies found anxiety sensitivity linked to coping-motivated cannabis use and problematic use patterns, but not to whether or how often someone uses cannabis.
Study of 95,645 Northern California teens found cannabis retail bans associated with lower psychotic disorder rates, and greater retail density linked to higher rates of anxiety and depressive disorders.
Canadian ED chart review found the profile of patients presenting with suicidality and cannabis use remained stable from immediately post-legalization to two years later, despite increased population cannabis use.
Study found socially anxious male emerging adults with high impulsivity were at greatest risk for coping-motivated cannabis use and related problems, suggesting a specific vulnerability profile.
Study of 709 Lithuanian young adults found childhood sexual abuse predicted cannabis and other substance use, while verbal abuse showed unexpected negative associations, challenging ACE summation approaches.
12-month UK study found adolescents were 3.26 times more likely to develop cannabis use disorder than young adults, with baseline CUD as the other significant predictor. Use frequency, gender, and other factors were not significant.
Study of 108 Dutch people with psychotic disorders found pain did not predict cannabis use, but those on less-sedating antipsychotics used more cannabis, suggesting different motivations than pain relief.
Longitudinal study of 788 people with bipolar disorder found within-person increases in cannabis use frequency predicted higher suicidal ideation at subsequent timepoints, alongside effects of substance use impairment.
Survey of 493 Polish students found 31% used marijuana for mental health alongside high rates of other complementary therapies, with marijuana users showing worse depressive symptoms and barriers to professional care driving self-treatment.
Survey of 3,389 cannabis users found those who first used for self-medication consumed more THC and had worse mental health than those who started for social reasons, suggesting initial motivation predicts later outcomes.
Health assessments of 710 Aboriginal and Torres Strait Islander youth found 72% were not depressed, with absence of marijuana use among key protective factors alongside exercise, sport, and absence of other adversities.
Longitudinal sibling study of 1,261 high-risk adolescents found cannabis use was not associated with suicidal thoughts or behaviors after controlling for shared genetic and environmental influences.
Review of comorbid cannabis use and mood disorders in adolescents found bidirectional reinforcement during a critical developmental period, requiring integrated assessment and treatment approaches.
National survey data showed adolescents with depression or bipolar disorder who use cannabis had significantly higher rates of suicidal ideation and attempts compared to non-users with the same diagnoses.
A 6-month observational study of 58 patients found cariprazine significantly improved both schizophrenia symptoms and cannabis dependence, with large improvements across all outcome measures.
Study of 223,068 Australian births found children exposed to maternal cannabis use disorder had 79% higher anxiety risk and 2.5x higher PTSD risk.
Australian population study found children of mothers with cannabis use disorder during pregnancy had 3.5x higher risk of disruptive behavioral disorders across all exposure windows.
Review found the endocannabinoid system is a promising treatment target for child and adolescent psychiatric disorders, but compounds targeting it without cannabis's side effects need further development.
Systematic review found only 11 total studies on technology-based interventions for cannabis use in psychosis, despite the rapid growth of digital mental health tools.
Daily diary study found college students with ADHD used cannabis more frequently, driven specifically by stronger motivation to cope with negative emotions.
Colorado surveillance data showed 13.3% of birthing individuals used cannabis perinatally, with pregnancy depression doubling the odds. Most cited medical reasons during pregnancy but shifted to recreational use postpartum.
Study of 96,482 youth found cannabis use moderated the bullying-suicidality link in LGBTQ+ teens, while opioid and hallucinogen use dramatically increased suicide attempt risk.
A study tracking teens from age 13 to 25 found early-onset escalating cannabis users had 8x higher odds of cannabis use disorder and 3x higher depression risk.
A study of 412 young adults found cannabis use was associated with paranoid thinking only in those with a history of childhood trauma, not in those without.
College students with type 1 diabetes: 41% used marijuana, with grit and illness acceptance protective while depression increased risk.
Blocking FABP5 prevented stress-induced anxiety and depression in rats while preserving hippocampal neurogenesis.
A 15-year French survey of 150,000+ teens found that while fewer adolescents use cannabis today, those who do show much stronger associations with suicidal thoughts and antidepressant use than teen users did in 2008.
Among 822 adults with anxiety or depression, social support reduced medical cannabis use for non-disabled individuals but not for those with disabilities, suggesting disabled individuals use cannabis for needs beyond what social support provides.
Nearly 1.6 million cannabis use disorder cases were identified in U.S. mental health facilities over 10 years, peaking in 2018, with depression co-occurring in 30% and 60% of patients being male.
Prenatal cannabis exposure may delay GABA's developmental switch from excitatory to inhibitory—disrupting the precise timing that guides how the fetal brain wires itself.
Analysis of 150,992 college students showing organized sports participation moderates the link between cannabis use and depression, anxiety, and PTSD diagnoses.
Statewide Michigan study using both self-report and urine testing finds 1 in 6 pregnancies involved cannabis use, strongly linked to depression, adverse childhood experiences, and socioeconomic factors.
Qualitative study reveals low-income pregnant cannabis users are primarily motivated by emotional regulation and mental health needs, highlighting systemic barriers to support and informed decision-making.
Pilot study finds a 10-week walking program reduced prenatal cannabis use from 63% to 17% while improving physical activity, anxiety, and depression — with excellent retention.
National survey finds 1 in 5 older adults who use cannabis drive within 2 hours of consumption, with daily users, men, and those using for mental health at highest risk.
Washington State study of 4,144 cannabis users finds people with psychotic disorders experience significantly more adverse events — including physical symptoms beyond psychiatric exacerbation.
In a rigorous trial, pharmaceutical CBD altered brain waves and improved cognitive abilities in boys with severe autism—with blood CBD levels predicting the brain changes.
National survey of nearly 70,000 U.S. teens found THC vaping linked to depression while CBD-only vaping was associated with higher anxiety symptoms — a surprising finding that challenges simple narratives.
Scoping review of RCTs found thin and mixed evidence for cannabis treating mental health conditions — CBD shows some anxiety promise but most psychiatric evidence remains inconclusive.
Study of 1,406 cannabis users found 28% had problematic social media use — higher than population norms — with TikTok, Twitter, depression, and cannabis risk all contributing factors.
Large-scale ABCD Study analysis found prenatal cannabis exposure associated with altered brain network connectivity, cognitive differences, and mental health symptoms in children.
A national study of 30,516 US adults found that Black/African American individuals with low income or mental health conditions had up to 5x higher odds of blunt use, with disparities widening with age.
A longitudinal study of 1,745 adults found that attachment anxiety amplifies the link between cannabis use and depression, with the combination of high anxiety and avoidance predicting the greatest depressive increases.
In one inpatient psychosis sample, cannabis users had higher MoCA scores than non-users.
Canadian national survey data shows the cannabis-mental health association roughly doubled from 2012 to 2022, with frequent users showing up to 5.4x higher suicidality prevalence by 2022.
Epilepsy monitoring unit data shows cannabis users have shorter stays and higher event capture rates, but significantly more depression, anxiety, and abuse histories than non-users.
People with psychosis increased their cannabis use by nearly 10 percentage points after recreational legalization — larger than general population increases — with the effect linked to retail store openings.
Meta-analysis of 7,515 patients found ~34% with cannabis-induced psychosis later developed schizophrenia spectrum disorder and ~11% developed bipolar disorder.
National survey finds 8.1% of US young adults co-vape nicotine and cannabis, with mental health distress, other substance use, and medical cannabis legalization as key risk factors.
Study finds 47.5% of patients on opioid treatment medication use cannabis, mostly to self-manage stress, anxiety, pain, and insomnia, without apparent worsening of treatment outcomes.
ABCD Study analysis of 7,777 children found prenatal cannabis risk was specific to post-awareness exposure, while alcohol risk was linked to pre-awareness use — timing matters differently for each substance.
Longitudinal study finds depression at 17 predicts cannabis problems at 23 only in sexually diverse youth, driven entirely by using cannabis to cope — a targetable pathway for prevention.
Network analysis reveals alcohol problems link uniquely to anxiety and suicidal thoughts while cannabis problems link to mania and dissociation, with patterns stable across ages 16-81.
First pilot trial of H4 deep brain stimulation for cannabis use disorder found the treatment feasible and tolerable — laying groundwork for controlled efficacy trials.
Over a decade, the teen cannabis-distress link grew stronger, especially for frequent female users, while overall teen use declined.
A 12-week virtual group therapy program reduced cannabis use, cravings, depression, and anxiety with 68% retention.
Trauma patients who tested positive for THC on admission were 66% more likely to screen positive for post-traumatic stress symptoms.
Systematic review of 38 studies finds integrated CBT works for CUD with co-occurring conditions, and AI tools can enhance contingency management.
In 923,000+ veterans on opioids, cannabis linked to 11% more suicide attempts; tobacco to more attempts, deaths, and overdose deaths.
Qualitative study finds most new mothers who used cannabis in pregnancy continued postpartum, citing mental health and pain, while wanting better information about breastfeeding risks.
ABCD Study found racial discrimination in preteens linked to cannabis use intentions through a pathway of increased perceived accessibility and decreased perceived harm.
Review mapped how cannabinoids interfere with drug metabolism through CYP450 enzymes, potentially altering effectiveness of antidepressants, blood thinners, opioids, and more.
Longitudinal study of 293 families finds prenatal tobacco-cannabis co-exposure leads to childhood behavioral problems through emotion regulation difficulties, a different pathway than tobacco alone.
ABCD Study found early adolescents follow distinct trajectories of cannabis expectancy development, with family monitoring and peer substance use as key factors.
Survey of 327 college students finds lack of belonging drives cannabis use indirectly through depression and anxiety, suggesting mental health support may be key.
Study finds coping-oriented cannabis use is driven by the combination of anxiety sensitivity and positive cannabis expectations, explaining previous inconsistent findings.
Pilot study found veterans with PTSD who achieved 12 weeks of cannabis abstinence saw 71% symptom reduction vs. 37% in those who continued using.
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.
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.
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.
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.
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.
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.
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.
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.
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.
Study of 162,532 US teens found dose-dependent links between cannabis use frequency and worse academic performance, self-regulation, and emotional states, even at monthly use levels, with younger teens more vulnerable.
Analysis of 98,820 All of Us participants found a nonlinear relationship between discrimination and cannabis use, with associations varying significantly across sexual orientation and gender identity groups.
Study of 1,992 Canadian veterans found regular cannabis users had 2-4 times the odds of chronic pain, mental disorders, and suicidal ideation, but also 5.6 times the odds of seeking professional help.
Scoping review finds no controlled evidence supporting cannabinoids for OCD, while psilocybin shows a stronger signal for treatment-resistant cases among the 40-60% of patients who do not respond to standard treatments.
Review found prenatal cannabis exposure reduces placental inflammation markers, which was linked to behavioral issues in offspring, though research is still early.
ABCD Study found prenatal tobacco and marijuana exposure linked to children's behavior problems, with tobacco specifically altering connectivity between attention and default mode brain networks.
ABCD Study found adolescents' mental health improved when household members quit cannabis, mediated by reduced family conflict and better sleep.
Interviews with 23 veterans revealed they value cannabis for health but get information from peers and dispensaries rather than clinicians, who they see as judgmental or uninformed.
NSDUH analysis found 7% of pregnant individuals use cannabis, driven by psychological distress (6x odds) and polysubstance use, while risk perception strongly deterred use.
National survey of 52,525 people found elevated substance use including cannabis across all sexual minority groups, extending to those using newer identity labels.
Large Kaiser study found adolescent cannabis use associated with significantly higher rates of psychotic, bipolar, depressive, and anxiety disorders diagnosed through age 25.
German health insurance data from 4 million youth showed cannabis-related diagnoses rose 22% (2013-2022), with 78% having co-occurring psychiatric disorders, especially depression.