Trial PaperAnxiety DisordersDepressive DisordersSubstance Use Disorders (SUD)Headache Disorders (Cluster & Migraine)SuicidalitySchizophreniaSafety & Risk ManagementChronic PainPsilocybin

Psilocybin-assisted psychotherapy for methamphetamine use disorder: A pilot open-label safety and feasibility study

In a single‑arm, open‑label pilot of 15 people with methamphetamine use disorder, outpatient psilocybin‑assisted psychotherapy (single 25 mg oral dose with preparatory and integration sessions) was feasible and well tolerated with no serious adverse events, and was associated with reductions in self‑reported methamphetamine use and craving at 28 and 90 days; a larger randomised trial is required to confirm efficacy and safety.

Authors

  • Paul Liknaitzky
  • Gillinder Bedi

Published

Addiction
individual Study

Abstract

Background & Aims There are few effective treatments for methamphetamine use disorder, despite increasing global demand. Here, we assessed the safety and feasibility of outpatient psilocybin‐assisted psychotherapy for methamphetamine use disorder.

Design

Single arm, open label pilot study.

Setting

Outpatient public stimulant treatment program at St. Vincent's Hospital, Sydney, Australia.

Participants

We recruited 15 participants that were ≥25 years old, seeking treatment for methamphetamine use, using methamphetamine ≥4 days/month at screening, and without serious mental illness or contraindicated medical conditions or medications.

Intervention

Participants received three preparatory psychotherapy sessions over two weeks before a single psilocybin dosing session (25 mg oral), followed by two integration psychotherapy sessions over one week. Psychotherapy included elements of motivational enhancement and acceptance and commitment therapy. Participants were followed for 90 days post psilocybin‐assisted psychotherapy session.

Measurements

Primary endpoints were safety (as measured by adverse events over the trial and vital signs during psilocybin dosing) and feasibility (as measured by enrolment and dropout rates), and secondary endpoints included measuring self‐reported methamphetamine and other illicit drug use, drug craving, depression, anxiety, stress and quality of life measures.

Findings

Of 56 participants pre‐screened, 15 were eligible and enrolled, 14 completed the intervention and 13 completed 90‐day post‐dose follow‐up.”. No serious adverse events (AEs) occurred, and the seven treatment related AEs were self‐limiting and mild to moderate in severity. AEs included hypertension during the dosing session and headache (n = 4), nausea (n = 1) and noise sensitivity (n = 1) within the week following the dose. Methamphetamine use (over the prior 28 days) was observed to be higher at screening (median 12 days, IQR 7–16, n = 15) relative to day 28 (median 0 days, IQR 0–2, n = 13) and 90 (median 2 days, IQR 1–4, n = 14) post psilocybin. [Correction added on 20 November 2025, after first online publication: In the preceding sentence, ‘lower’ has been changed to 'higher' in this version.] Methamphetamine craving was also observed to be lower while quality of life, depression, anxiety, and stress were observed to be higher at days 28 and 90 follow‐up relative to baseline.

Conclusions

Psilocybin assisted psychotherapy for methamphetamine use disorder was feasible to implement in an outpatient setting and did not appear to generate safety concerns. A larger randomised controlled trial is required to confirm efficacy and safety.

Available with Blossom Pro

Research Summary of 'Psilocybin-assisted psychotherapy for methamphetamine use disorder: A pilot open-label safety and feasibility study'

Introduction

Methamphetamine (MA) is a widely used psychostimulant and, with other amphetamine-type stimulants, ranks as the second most commonly used illicit drug globally. MA use is associated with substantial individual harms (cardiovascular disease, suicidality, psychosis, depression, anxiety, infectious disease risk and mortality) and societal harms (homelessness, family disruption and crime). There are no approved pharmacotherapies for methamphetamine use disorder (MAUD) and psychosocial interventions produce only modest effects; contingency management shows promise but faces implementation barriers. Early-phase clinical trials indicate that psilocybin-assisted psychotherapy (PAT) can be safe and preliminarily efficacious for several mental health conditions and for some substance use disorders, and its putative effects on cognitive and neural plasticity make it a candidate treatment for MAUD. Safety and pragmatic questions remain, however, including limited drug–drug interaction data and uncertainty about how psychedelic effects interact with stimulant-related psychosis risk. Knock and colleagues conducted a pilot open-label study to evaluate the safety and feasibility of outpatient psilocybin-assisted psychotherapy for treatment‑seeking adults with MAUD in a public addiction outpatient setting. The study aimed primarily to assess feasibility metrics and adverse event profiles when delivering a single 25 mg oral psilocybin dose with preparatory and integration psychotherapy; efficacy was not the primary objective given the pilot design.

Expert Research Summaries

Go Pro to access AI-powered section-by-section summaries, editorial takes, and the full research toolkit.

Full Text PDF

Full Paper PDF

Pro members can view the original manuscript directly in the browser.

Study Details

References (23)

Papers cited by this study that are also in Blossom

The pharmacology of psilocybin

Passie, T., Seifert, J., Schneider, U. et al. · Addiction Biology (2002)

Long-term follow-up of psilocybin-facilitated smoking cessation

Johnson, M. W., Garcia-Romeu, A., Griffiths, R. R. · The American Journal of Drug and Alcohol Abuse (2016)

562 cited
The abuse potential of medical psilocybin according to the 8 factors of the Controlled Substances Act

Johnson, M. W., Griffiths, R. R., Hendricks, P. S. et al. · Neuropharmacology (2018)

Human hallucinogen research: guidelines for safety

Johnson, M. W., Richards, W. A., Griffiths, R. R. · Journal of Psychopharmacology (2008)

Psilocybin-assisted treatment for alcohol dependence: a proof-of-concept study

Bogenschutz, M. P., Forcehimes, A. A., Pommy, J. A. et al. · Journal of Psychopharmacology (2015)

The Challenging Experience Questionnaire: Characterization of challenging experiences with psilocybin mushrooms

Barrett, F. S., Bradstreet, M. P., Leoutsakos, J. M. S. et al. · Journal of Psychopharmacology (2016)

Psilocybin can occasion mystical-type experiences having substantial and sustained personal meaning and spiritual significance

Griffiths, R. R., Richards, W. A., Mccann, U. et al. · Journal of Psychopharmacology (2006)

Emotional breakthrough and psychedelics: validation of the emotional breakthrough inventory

Roseman, L., Haijen, E. C. H. M., Idialu-Ikato, K. et al. · Journal of Psychopharmacology (2019)

Show all 23 references
Validation of the revised Mystical Experience Questionnaire in experimental sessions with psilocybin

Barrett, F. S., Johnson, M. W., Griffiths, R. R. · Journal of Psychopharmacology (2015)

Therapeutic effect of psilocybin in addiction: A systematic review

van der Meer, P. B., Fuentes, J. J., Kaptein, A. A. et al. · Frontiers in Psychiatry (2023)

Effects of Psilocybin-Assisted Therapy on Major Depressive Disorder

Davis, A. K., Barrett, F. S., May, D. G. et al. · JAMA Psychiatry (2021)

1015 cited
Pilot study of the 5-HT2AR agonist psilocybin in the treatment of tobacco addiction

Johnson, M. W., Garcia-Romeu, A., Cosimano, M. P. et al. · Journal of Psychopharmacology (2014)

Adverse events in clinical treatments with serotonergic psychedelics and MDMA: A mixed-methods systematic review

Breeksema, J. J., Kuin, B. W., Kamphuis, J. et al. · Journal of Psychopharmacology (2022)

Optimal dosing for psilocybin pharmacotherapy: Considering weight-adjusted and fixed dosing approaches

Garcia-Romeu, A., Barrett, F. S., Carbonaro, T. M. et al. · Journal of Psychopharmacology (2021)

Assessing expectancy and suggestibility in a trial of escitalopram v. psilocybin for depression

Szigeti, B., Weiss, B., Rosas, F. E. et al. · Psychological Medicine (2024)

Does psychedelic therapy have a transdiagnostic action and prophylactic potential?

Kočárová, C., Horacek, J., Carhart-Harris, R. L. · Frontiers in Psychiatry (2021)

73 cited
51 cited
How does psilocybin therapy work? An exploration of experiential avoidance as a putative mechanism of change

Zeifman, R. J., Wagner, A. C., Monson, C. M. et al. · Journal of Affective Disorders (2023)

47 cited
The use of the psychological flexibility model to support psychedelic assisted therapy

Watts, R., Luoma, J. B. · Journal of Contextual Behavioral Science (2020)

Cited By (1)

Papers in Blossom that reference this study

Your Personal Research Library

Go Pro to save papers, add notes, rate studies, and organize your research into custom shelves.

Psilocybin-assisted psychotherapy for... — Research Summary & Context | Blossom