Neurocognitive DisordersMicrodosingLSDPsilocybin

Potential safety, benefits, and influence of the placebo effect in microdosing psychedelic drugs: A systematic review

This systematic review (2020) of (mostly) observational studies on microdosing psychedelics (LSD & psilocybin) finds that it is experienced both positively and negatively by participants (n=3,619).

Authors

  • Gonzalo Ona
  • José Carlos Bouso

Published

Neuroscience and Biobehavioral Reviews
meta Study

Abstract

“Microdosing psychedelic drugs-that is, taking sub-behavioral doses of lysergic acid diethylamide (LSD) or psilocybin-is a growing practice in Western societies. Taken mainly for creative or mood-enhancing purposes, thousands of users are increasingly being exposed to (micro)doses of psychedelic drugs. In this systematic review, we searched the available evidence from human studies, focusing our results in terms of three main axes: efficacy, safety, and the influence of the placebo effect in microdosing practices. While the available evidence has some strengths (e.g. large sample sizes, robust methodologies) there are also remarkable limitations (e.g. gender bias, heterogeneity of dosing schedules and drugs used). Highly contradictory results have been found, showing both the benefits and detriments of microdosing in terms of mood, creative processes, and energy, among other regards. This review provides a general overview of the methods and approaches used, which could be useful for improving future studies.”

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Research Summary of 'Potential safety, benefits, and influence of the placebo effect in microdosing psychedelic drugs: A systematic review'

Introduction

The paper frames microdosing—the periodic use of very low doses of classical psychedelics such as LSD and psilocybin—as a distinct phenomenon from pharmacological "microdosing" or Phase 0 trials. Whereas Phase 0 uses sub-therapeutic exposures to obtain mechanistic information, recreational and self-administered microdosing typically employs doses (for example <25 µg LSD) that do not produce overt psychoactive impairment but are reported by users to produce subtle effects on mood, cognition and wellbeing. The authors note growing public interest since the 2010s, popularised accounts and online protocols, and emerging preclinical data that psychedelics can enhance neural plasticity and neurogenesis via 5-HT2A signalling, which has prompted interest in possible applications ranging from mood disorders to neurodegenerative disease.

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Study Details

References (31)

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