CoChat
Sign Up
Cited by 74Psychedelics and Drug StudiesTreatment of Major DepressionReligion, Spirituality, and Psychology

The therapeutic potential of psilocybin: a systematic review

Open access
van Amsterdam, Jan, van den Brink, Wim·2022·Expert Opinion on Drug Safety
DOI 10.1080/14740338.2022.2047929
Open this paper in CoChat — free accountOpen PDF

Abstract

INTRODUCTION: Psychedelic drugs were used quite extensively before their prohibition in 1968 which delayed research. However, since the 1990s, studies on the potential therapeutic benefits of psychedelics have rapidly increased. AREAS COVERED: This systematic review provides an overview of the clinical effects of psilocybin in the treatment of a variety of mental disorders. Only (randomized) clinical trials were selected. A total of 11 studies (15 publications) were selected, including seven randomized controlled trials (eight publications) and four single arm open-label studies (seven publications). In total, 488 patients were included in the selected studies: 333 patients treated with psilocybin and 155 patients treated with (active) placebo. In nine studies, psychotherapeutic support was provided as an integral part of the psilocybin treatment. The findings of these studies collectively show that psilocybin has a positive benefit-risk balance in the treatment of various mental disorders with an immediate and prolonged effect following 1-3 doses of psilocybin and a few (serious) adverse events. EXPERT OPINION: Psilocybin - mostly combined with psychotherapy or psychotherapeutic support - shows a promise as a treatment for various (treatment-resistant) mental disorders. Larger double-blind RCTs with objective (long-term) outcomes are needed to confirm these findings before standard clinical use of psilocybin can be considered.

The claims and statistics of this paper haven’t been checked yet.

Run the check — free, no account needed. It reads the open-access text and checks the sources it cites.

A few free checks a day · papers already verified open instantly · results are public

Integrity signals

Registry

Crossref · 10.1080/14740338.2022.2047929

Cites

46 of 46 references verified0 citation errors · 0 not checkable

Statistics

Claims the paper makes

The claims and statistics of this paper haven’t been checked yet.

Run the check — free, no account needed. It reads the open-access text and checks the sources it cites.

A few free checks a day · papers already verified open instantly · results are public

Claims other papers make about this one

Each is checked against this paper’s own text: does it say what the citing paper says it does?

  • Most contemporary studies of PAT have included two or more psilocybin dosing sessions supported with psychotherapy.

    “Most contemporary studies of PAT have included two or more psilocybin dosing sessions supported with psychotherapy [13,15].”

    From Psilocybin‐assisted psychotherapy for methamphetamine use disorder: A pilot open‐label safety and feasibility study. (2025) · cites this paper as [13]

    The Treatment outcome section reports that 9 of 11 studies provided psychotherapeutic support as an integral part of psilocybin treatment. The Discussion says the studies used 1–3 psilocybin administrations, but does not establish that most used two or more dosing sessions; that frequency is unsupported by the cited review. (LLM, conf=0.82)

    Experimental — accuracy not yet measured

  • Psilocybin is a serotonergic classic psychedelic that has been examined in combination with psychological support as a promising treatment option in clinical trials for various disorders.

    “Psilocybin (4-phosphryloxy-N,N-dimethyltryptamine) is a serotonergic classic psychedelic (19–25) that has been examined in combination with psychological support as a promising treatment option in clinical trials for various disorders (26–28).”

    From Acute and post-dosing effects of single-dose psilocybin for obsessive-compulsive disorder in a randomized, double-blind, placebo-controlled trial: an interpretative phenomenological analysis (2025) · cites this paper as [28]

  • Early phase clinical trials suggest that psilocybin, when delivered in combination with psychotherapy, is safe, feasible and preliminarily efficacious for alleviating symptoms of mental health conditions, including treatment-resistant depression.

    “Early phase clinical trials suggest that psilocybin, when delivered in combination with psychotherapy, is safe, feasible and preliminarily efficacious for alleviating symptoms of mental health conditions, including treatment-resistant depression [13].”

    From Psilocybin‐assisted psychotherapy for methamphetamine use disorder: A pilot open‐label safety and feasibility study. (2025) · cites this paper as [13]

  • A fixed 25 mg dose was selected as optimal in phase-II/III studies of PAT and equally effective as weight-based dosing.

    “A fixed 25 mg dose was selected as this dose was demonstrated as optimal in phase-II/III studies of PAT, and in limited dose-finding studies [13], and is equally as effective as weight-based dosing whilst being easier to implement [29].”

    From Psilocybin‐assisted psychotherapy for methamphetamine use disorder: A pilot open‐label safety and feasibility study. (2025) · cites this paper as [13]

    The Article highlights report promising preliminary results for 25 mg versus 1 mg psilocybin and list other studies using doses per 70 kg (page not available). But [29] is attached to the claim that fixed dosing is equally effective as weight-based dosing and easier to implement. Our copy does not address that comparison; searches for fixed versus weight-based dosing and dose optimization found no supporting passage. (LLM, conf=0.72)

    Experimental — accuracy not yet measured

Self-check

Percentages, sums and reported differences re-computed from the paper’s own numbers.

The self-check needs the paper’s full text.

Cites

Flagged first, then by citations

Research works printed but not linked: 2

  1. [40]40. van Elk M. Neuroscientific and psychological explanations for the therapeutic effects of psychedelics. Tijdschr Psychiatr. 2020;62 (8):677-683.
  2. [52]52. Wark C. A social and cultural history of the federal prohibition of psilocybin. Dissertation. 2007. Available from: https://mospace. umsystem.edu/xmlui/bitstream/handle/10355/4653/research.pdf? sequence=3&isAllowed=y. Cited 2021 Dec 20.

Cited by

Sorted by citations

Related

Authors
van Amsterdam, J., & van den Brink, W.
Affiliations
Department of Psychiatry, Academic Medical Center University of Amsterdam, Amsterdam, The Netherlands
ORCID
van Amsterdam, Jan
Venue
Expert Opinion on Drug Safety
Publisher
Informa UK Limited
Published
2022-03-02
Volume
21
Issue
6
Pages
833-840
ISSN
  • 1474-0338 (ISSN-L)
  • 1744-764X
DOI
10.1080/14740338.2022.2047929
OpenAlex
W4214511680
Cited by
74
References
46
Citations by year
2026: 3 · 2025: 16 · 2024: 42 · 2023: 9 · 2022: 4
FWCI
2.96
Type
journal article
Language
en
Open access
Licence
other-oa
Locations
  • Expert Opinion on Drug Safety (publishedVersion)
  • PubMed (publishedVersion)
  • Pure Amsterdam UMC (acceptedVersion, other-oa)
  • Data Archiving and Networked Services (DANS) (submittedVersion)
Funders
no financial support
Topics
  • Social Sciences › Psychology › Clinical Psychology › Psychedelics and Drug Studies
  • Health Sciences › Medicine › Pharmacology › Treatment of Major Depression
  • Social Sciences › Health › Religion, Spirituality, and Psychology
Keywords
psilocybin, psychedelics, mental illness, treatment-resistant mental illness, adverse events, benefit-risk balance, psychedelic therapy
MeSH terms
Mental Disorders, Double-Blind Method, Hallucinogens, Humans, Psilocybin, Randomized Controlled Trials as Topic

About these checks

Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.

Statistics and arithmetic are recomputed, not judged.

Confidence bands are shown only for fields calibrated on our annotated test set. None is calibrated yet, so no band is shown.

What counts as a claim ›How we measure confidence ›How we check this ›

Are you an author, or do you see a problem with this page? Request a review