Cessation and reduction in alcohol consumption and misuse after psychedelic use

Garcia-Romeu and colleagues frame the study within a context of high prevalence and poor treatment uptake for alcohol use disorder (AUD), noting limitations of current pharmacotherapies and psychosocial interventions, including high relapse rates. Earlier clinical research from the mid-20th century and recent pilot studies suggest that classic serotonergic psychedelics (notably LSD and psilocybin) may reduce problematic alcohol use; particular subjective qualities of the drug experience (for example, mystical-type effects and psychological insight) have been proposed as processes that might facilitate lasting behaviour change. This study set out to systematically characterise instances in which naturalistic (nonclinical) psychedelic use was followed by self-reported cessation or reduction in alcohol misuse. Using an anonymous online survey, the investigators sought to describe participant characteristics, the psychedelic experiences implicated, changes in alcohol use and related symptoms, and associations between psychedelic experience features (dose, mystical and insightful qualities, persisting personal meaning) and changes in alcohol consumption. The authors hypothesised that greater mystical-type subjective qualities would be associated with larger reductions in alcohol use.

The researchers conducted a cross-sectional, anonymous online survey from October 2015 to August 2017, recruiting via social media and websites focused on drug discussion and research. Inclusion criteria required participants to be aged 18 or older, fluent in English, to have met DSM-5 criteria for AUD retrospectively, and to report a classic psychedelic experience outside a university or medical setting that they attributed to a subsequent reduction or cessation of alcohol use. The study was approved by an institutional review board and participants gave consent by choosing to complete the survey; no financial compensation was provided. Survey measures captured demographics, lifetime drug use, and retrospective alcohol use and related distress in the year prior to, and since, the single psychedelic experience to which participants attributed their change (the "reference psychedelic experience"). Standardised instruments included the AUDIT-C (with thresholds of ⩾3 for women and ⩾4 for men indicating potential misuse), a DSM-5 AUD symptom checklist (11 items, with 2–3 symptoms = mild, 4–5 = moderate, ⩾6 = severe), the Alcohol Urge Questionnaire (AUQ) for craving, and the 30-item Mystical Experience Questionnaire (MEQ30). Participants also rated persisting effects such as personal meaning, psychological insight, spiritual significance, and change in well-being. Adverse effects and alcohol withdrawal symptoms after the reference experience were queried and compared to prior quit attempts. Analyses comprised descriptive statistics, Wilcoxon matched-pairs signed rank tests comparing pre- and post-reference experience alcohol measures (AUDIT-C, DSM-5 symptom totals, AUQ, drinks per week), and Pearson correlations between AUDIT-C change scores and candidate predictors (demographics, dose, MEQ30, persisting effects, baseline alcohol variables). Based on correlation patterns, a path analysis was specified and estimated with maximum likelihood and robust standard errors in MPlus v.7.0 to test a model linking pre-AUDIT-C and alcohol distress, dose, acute mystical and insight experiences, persisting personal meaning, and AUDIT-C change score. Model fit indices were reported.

From 4095 individuals who clicked recruitment ads, 1429 met inclusion criteria and began the alcohol survey; 512 completed it. After excluding participants whose reference experience was within three months of the survey, those who did not meet at least DSM-5 mild AUD prior to the experience, and those who implicated non-classic-psychedelics (for example MDMA), the final sample comprised 343 adults. The sample was predominantly White (89%), male (78%), US-based (60%), with a mean age of 31.4 years (SD = 10.8). Lifetime use was highest for alcohol and cannabis; LSD and psilocybin were the most commonly implicated psychedelics in the reference experience. Prior to the reference psychedelic experience, 72% met criteria for severe AUD, with a mean of 7.3 (SD = 2.7) DSM-5 symptoms, a mean self-reported 25.5 (SD = 21.5) drinks per week, and an AUDIT-C mean of 8.5 (SD = 2.2). Most respondents (68%) had not received formal treatment for alcohol use prior to the experience. The reference psychedelic experience most commonly involved LSD (38%) or psilocybin (36%), with 54% reporting a "moderate" dose and 29% a "high" dose; 75% reported their experience had occurred at least one year earlier. Intentions for the session were typically psychological (62%) or spiritual (39%), and only 10% reported intending specifically to reduce or quit drinking. Subjective effects were notable: mean MEQ30 scores were about 67% of the maximum, and 39% met criteria for a "complete mystical experience" (⩾60% on each MEQ30 subscale). Most respondents rated the experience among the 10 most personally meaningful (80%) and among the 10 most psychologically insightful (74%); 79% reported increased well-being or life satisfaction following the experience. Concerning safety, 89% reported no persisting adverse effects beyond acute drug action; 5% reported persisting adverse effects of mostly low to moderate severity, and two individuals reported extreme-severity effects (panic/spiritual crisis, and significant cognitive alteration). Alcohol-related outcomes showed large, statistically significant reductions from pre- to post-reference experience. Mean drinks per week fell from 25.5 (SD = 21.5) to 4.3 (SD = 10.2). Mean AUDIT-C scores decreased by 5.8 (SD = 3.0), from 8.5 (SD = 2.2) to 2.7 (SD = 2.5), placing many respondents below risky-drinking thresholds. At the time of survey response, 83% no longer met DSM-5 criteria for AUD, with an average of 1.0 (SD = 2.1) symptoms endorsed since the reference experience. Wilcoxon matched-pairs signed rank tests for AUDIT-C, DSM-5 symptoms, AUQ craving, and drinks per week all indicated pre-to-post reductions at p < 0.0001. Alcohol withdrawal symptoms were still reported by many respondents after the reference experience (for example craving 58%, depression 58%, anxiety 55%), but among those who had experienced a given symptom previously, a large proportion reported it to be "much less severe" after the reference psychedelic event compared with prior quit attempts (for craving, 69% reported much less severe). Correlation analyses showed AUDIT-C change scores were positively associated with psychedelic dose, intensity of acute mystical experiences, ratings of personal meaning and insight, baseline AUDIT-C and AUD-related distress, number of AUD symptoms prior to the experience, and years with a drinking problem. In the path analysis, higher pre-AUDIT-C and greater alcohol distress predicted larger AUDIT-C change scores directly; higher psychedelic dose predicted greater acute insight and mystical effects, which in turn predicted greater personal meaning; and personal meaning predicted AUDIT-C change. Indirect effects from acute insight and mystical effects to AUDIT-C change via personal meaning were statistically significant. The model fit indices were reported as excellent: χ2(1, n = 343) = 8.28, p = .687; RMSEA = .00 (95% CI [.00, .05]); standardized root-mean-square residual = .025. Beyond alcohol, many participants reported improvements in other life domains following the reference experience, including interpersonal relationships (76%), diet (63%), exercise (55%), and work/career (53%). A minority reported deterioration in some domains.

Garcia-Romeu and colleagues interpret their findings as indicating that, for some individuals, naturalistic psychedelic use outside formal treatment settings is followed by pronounced and enduring reductions in alcohol misuse. The pattern of results—large reductions in drinks per week, AUDIT-C scores, DSM-5 symptom counts, and craving—aligns with historical clinical studies of LSD, recent pilot trials of psilocybin-assisted treatment for alcohol dependence, and observational reports from religious and nonclinical contexts. Although only 10% of respondents intended to change their drinking before the reference experience, many reported broader shifts in values or priorities and increased belief in their ability to abstain, suggesting that psychological or spiritual motivations can indirectly produce reductions in alcohol use. The authors highlight several plausible mechanisms discussed in prior literature and supported by their data: mystical-type experiences, psychological insight, increased self-efficacy and motivation, reductions in craving and affective withdrawal symptoms, and possible neurobiological or anti-inflammatory effects. Notably, the path analysis suggested a chain in which higher psychedelic dose related to stronger acute mystical and insight effects, which increased the personal meaning of the experience, and that personal meaning was linked to larger reductions in alcohol consumption. The investigators underscore that psychological insight, alongside mystical-type effects, may represent an important mechanism of behaviour change. Important limitations noted by the authors temper causal inference. The design was cross-sectional and retrospective, relying on self-selected volunteers who were recruited because they reported reductions in alcohol use following psychedelic use; therefore selection bias, recall bias, and the inability to verify substance use or timings constrain interpretation. The study cannot estimate prevalence or efficacy of psychedelic-associated AUD remission relative to alternative pathways, nor assess increases in alcohol use after psychedelic use because the sample was purposively selected for reductions. The authors also acknowledge limited generalisability given the sample's demographic homogeneity (predominantly White males). Finally, some participants reported only temporary reductions, mirroring relapse patterns seen in established treatments. Despite these caveats, the authors argue that the results, together with historical trials and contemporary pilot studies, justify further prospective, controlled research into psychedelic-assisted treatment for AUD. They recommend collaborative efforts among clinical researchers, funding agencies, and regulatory bodies to accelerate such work, noting logistical and regulatory barriers and the need for rigorous investigation of safety, mechanisms, and clinical efficacy.