The impact of psychedelics on patients with alcohol use disorder: a systematic review with meta-analysis

ObjectivesCritique the available systematic review and de novo assessment of the role of psychedelics in the treatment of alcohol use disorder.MethodsA systematic literature search of PubMed was completed from 1960 to 9/9/2023. We pooled randomized controlled trials comparing psychedelics to control therapy for the treatment of alcohol use disorder.ResultsAt the first recorded follow-up, LSD [n = 3, Odds Ratio (OR) 1.99 (95% Confidence interval (CI): 1.10 to 3.61)] and any psychedelic [n = 4, OR 2.16 (95%CI: 1.26 to 3.69)] enhanced the odds of patients achieving abstinence or a substantial reduction in drinking alcohol versus placebo in randomized, double-blind, placebo-controlled trials. When the inclusion criteria were relaxed to include controlled trials without double-blinding or placebo control, LSD [n = 5, OR 1.79 (95%CI: 1.36 to 2.34)] and any psychedelic therapy [n = 6, OR 1.89 (95%CI: 1.42 to 2.50)] still enhanced the odds of patients achieving abstinence or a substantial reduction in drinking alcohol. Four of 6 trials had high risk of bias and other methodological issues. One trial found an instance of suicidal ideation as well as transient increases in blood pressure that requires further exploration before the balance of benefits to harms can be determined.ConclusionsThe use of psychedelics to treat alcohol use disorder is promising, but the weaknesses in the literature base preclude making definitive statements about its value. Future trials with greater methodological rigor are needed. Lysergic acid diethylamine (LSD) and psilocybin (hallucinogenic mushrooms) are psychedelics that have been studied in patients with alcohol use disorder (chronic issue with heavy or problem drinking). When all the studies are pooled together in a meta-analysis, the odds of being able to refrain from drinking alcohol or to substantially reduce the amount of alcohol consumed was enhanced by 89%. This is a promising finding that if bore out in additional studies, especially those with higher study quality, would be a major advance in patients with alcohol use disorder. We cannot make more definitive conclusions because all the LSD studies were published between 1966 and 1970 which may not reflect contemporary practice and most of the studies had methodological weaknesses that reduce confidence in the studies to prove the benefits. It is heartening that the single psilocybin trial from 2022 was of higher methodological quality, reflected contemporary practice, and still showed positive effects.