Evidence by molecule
How strong the research is for each treatment, on our four-level evidence scale. Each links to the full molecule guide.
A 96-person phase 2 trial found three infusions plus therapy led to more days without drinking at six months. Confidence intervals were wide.
One 95-person randomised trial found fewer heavy drinking days over 32 weeks than an active placebo, both given alongside therapy.
A meta-analysis of six trials from the 1960s and 1970s (536 people) found better outcomes with a single LSD dose. The trials used older methods and haven't been repeated with modern designs.
5-MeO-DMT: Alcohol use disorder Very low
An open-label pilot of 12 people found fewer drinking days after one dose of BPL-003 alongside therapy. There was no control group.
What the research shows
- Psilocybin: In a 95-person randomised trial, two psilocybin sessions alongside 12 weeks of therapy cut heavy drinking days to 9.7%, compared with 23.6% with an active placebo.1
- Ketamine: In a 96-person phase 2 trial, three infusions alongside relapse-prevention therapy led to more days without drinking at six months than placebo.2
- LSD: A 2012 meta-analysis of six trials from the 1960s and 1970s (536 people) found that a single dose roughly doubled the odds of improvement. Those trials don’t meet modern standards.3
- 5-MeO-DMT: In an open-label pilot of 12 people, abstinent days rose from 33% to 81% after one dose within a therapy program. There was no control group.4
- Other substances: Early, uncontrolled studies have looked at psilocybin for smoking5 and ibogaine for opioid use disorder.6 See the psilocybin and ibogaine guides.
Established treatments
Medicines, counselling, mutual-support groups and medically supervised withdrawal all have evidence for alcohol and substance use problems. Stopping alcohol suddenly after heavy use can be dangerous. Talk to a qualified health professional about your own situation.
Studies in the library
- Review of new drug options for opioid addiction, including ketamine and ibogaineOther · 2026 · Evidence: Low
- Interviews with 10 people given 5-MeO-DMT plus CBT for alcohol use disorderOpen-label trial · 2026 · Evidence: Very low
- Small open-label pilot of ibogaine for alcohol use disorder: heart rhythm changes seenOpen-label trial · 2026 · Evidence: Very low
- Single case report: ibogaine treatment followed by 17 months off ketamine, cocaine and alcoholCase report · 2026 · Evidence: Very low
- Ketamine and substance use disorders: pooled results from 15 randomized trialsMeta-analysis · 2026 · Evidence: Moderate
- A scoping review of how psychedelics affect thalamus-to-cortex brain circuitsSystematic review · 2026 · Evidence: Very low
- A review proposing two routes for turning ibogaine into a medicineSystematic review · 2026 · Evidence: Very low
- Review of 30 years of ibogaine research finds evidence too weak to support clinical useSystematic review · 2026 · Evidence: Low
- Psilocybin and DNA methylation changes in 37 people treated for alcohol use disorderRCT · 2026 · Evidence: Low
- Interviews with 10 people who used ibogaine for opioid detox in New ZealandCase series · 2026 · Evidence: Very low
- Review of human ibogaine research finds only three randomized trials and real cardiac risksSystematic review · 2026 · Evidence: Low
- Single psilocybin dose with therapy increased cocaine abstinence in a 40-person trialRCT · 2026 · Evidence: Moderate
- Review pools DMT studies for substance misuse and finds large but unreliable effectsMeta-analysis · 2026 · Evidence: Low
- Review of where psychedelic-assisted therapies stand in the clinic and in regulationOther · 2026 · Evidence: Very low
- Review of mescaline studies finds too little good evidence for psychiatric useSystematic review · 2026 · Evidence: Very low
- Psilocybin vs nicotine patch for quitting smoking: a pilot randomized trialRCT · 2026 · Evidence: Moderate
- Review finds little evidence that lesser-known tryptamine psychedelics help alcohol use disorderSystematic review · 2026 · Evidence: Low
- Review: how salvinorin A acts on opioid receptors rather than serotonin receptorsOther · 2026 · Evidence: Very low
- National survey links psychedelic use to opioid use disorder severity — in both directionsObservational · 2026 · Evidence: Low
- Review of how ibogaine might repair nerve insulation and brain energy useOther · 2026 · Evidence: Very low
- Review of 18 long-term studies on ayahuasca and mental and physical healthSystematic review · 2026 · Evidence: Low
- Scoping review of ibogaine for addiction: promise, patchy evidence and heart safety concernsSystematic review · 2026 · Evidence: Low
- Review of ketamine combined with psychotherapy: little proof the therapy part adds benefitSystematic review · 2026 · Evidence: Low
- Depression scores after ritual ayahuasca use tracked for six months in 280 patientsObservational · 2026 · Evidence: Low
- Review of ibogaine's heart risks: QT prolongation and dangerous arrhythmiasOther · 2026 · Evidence: Low
- What people said the day after psilocybin linked to staying off alcohol at 3 monthsRCT · 2026 · Evidence: Low
- Review of MAOI antidepressants mixed with psychedelics and other psychoactive drugsOther · 2026 · Evidence: Very low
- Review of 23 meta-analyses on psychedelic-assisted therapy for mental disordersSystematic review · 2025 · Evidence: Moderate
- What adverse events are reported for psychedelics and MDMA in a global safety databaseObservational · 2025 · Evidence: Low
- A review of ibogaine as a possible treatment for opioid dependenceOther · 2025 · Evidence: Very low
- What predicts who responds to psychedelic-assisted therapy? A review of 54 studiesSystematic review · 2025 · Evidence: Low
- Single dose of inhaled 5-MeO-DMT plus therapy in 13 people with alcohol use disorderOpen-label trial · 2025 · Evidence: Very low
- Nine people describe combining psychedelics with 12-Step recovery from addictionObservational · 2025 · Evidence: Very low
- Pooled review of 30 trials of MDMA and psychedelics for mental disordersMeta-analysis · 2025 · Evidence: Moderate
- Review of ayahuasca research finds little controlled evidence for mental health usesOther · 2025 · Evidence: Very low
- Review of side effects reported in 42 psilocybin trials involving 1,068 peopleSystematic review · 2025 · Evidence: Moderate
- Review pools 30 studies of psychedelics and ketamine for substance use disorderMeta-analysis · 2025 · Evidence: Low
- Review: how psychedelics and ketamine may reshape brain connections in depression, PTSD and addictionOther · 2025 · Evidence: Very low
- A new 70-item questionnaire to measure the subjective effects of ibogaineObservational · 2025 · Evidence: Low
References
- Bogenschutz MP, et al. Percentage of heavy drinking days following psilocybin-assisted psychotherapy vs placebo in the treatment of adult patients with alcohol use disorder: a randomized clinical trial. JAMA Psychiatry. 2022;79(10):953–962. Source
- Grabski M, et al. Adjunctive ketamine with relapse prevention-based psychological therapy in the treatment of alcohol use disorder. American Journal of Psychiatry. 2022;179(2):152–162. Source
- Krebs TS, Johansen PØ. Lysergic acid diethylamide (LSD) for alcoholism: meta-analysis of randomized controlled trials. Journal of Psychopharmacology. 2012;26(7):994–1002. Source
- Marsden J, et al. 5-Methoxy-N,N-dimethyltryptamine (5-MeO-DMT) for alcohol use disorder: an open-label, phase 2, proof-of-concept, clinical trial. Addiction. 2025. Source
- Johnson MW, et al. Pilot study of the 5-HT2AR agonist psilocybin in the treatment of tobacco addiction. Journal of Psychopharmacology. 2014;28(11):983–992. Source
- Brown TK, Alper K. Treatment of opioid use disorder with ibogaine: detoxification and drug use outcomes. American Journal of Drug and Alcohol Abuse. 2018;44(1):24–36. Source