Substance Use Disorders (SUD)Equity and Ethics

Adverse effects of psychedelics: From anecdotes and misinformation to systematic science

This narrative review finds that medical harms from classic psychedelics are generally minimal and that many persistent fears about psychological risks are not supported by systematic evidence, with most adverse effects arising in unregulated settings. The authors emphasise the need for rigorous clinical standards and balanced media reporting to prevent stigma and allow responsible research to continue.

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Authors

  • David Nutt

Published

Journal of Psychopharmacology
meta Study

Abstract

Background

Despite an increasing body of research highlighting their efficacy to treat a broad range of medical conditions, psychedelic drugs remain a controversial issue among the public and politicians, tainted by previous stigmatisation and perceptions of risk and danger.

Objective

This narrative review examines the evidence for potential harms of the classic psychedelics by separating anecdotes and misinformation from systematic research.

Methods

Taking a high-level perspective, we address both psychological and psychiatric risks, such as abuse liability and potential for dependence, as well as medical harms, including toxicity and overdose. We explore the evidence base for these adverse effects to elucidate which of these harms are based largely on anecdotes versus those that stand up to current scientific scrutiny.

Results

Our review shows that medical risks are often minimal, and that many – albeit not all – of the persistent negative perceptions of psychological risks are unsupported by the currently available scientific evidence, with the majority of reported adverse effects not being observed in a regulated and/or medical context.

Conclusions

This highlights the importance for clinicians and therapists to keep to the highest safety and ethical standards. It is imperative not to be overzealous and to ensure balanced media reporting to avoid future controversies, so that much needed research can continue.

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Research Summary of 'Adverse effects of psychedelics: From anecdotes and misinformation to systematic science'

Editorial

βBlossom's Take

This review is useful as a safety counterweight, because it sorts older alarmist claims from harms that are actually supported by evidence. Its main contribution is not to deny risk, but to show that many fears about classic psychedelics come from unregulated settings, which helps keep modern trial design and public debate on firmer ground.

Study Details

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