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

Microdosing psychedelic drugs like LSD or psilocybin is increasingly common in Western societies, primarily for enhancing mood or creativity. This systematic review of human studies examined efficacy, safety, and the role of placebo effects. The evidence shows strengths such as large sample sizes and robust methods, but also limitations like gender bias and inconsistent dosing. Results are highly contradictory, with some studies reporting benefits and others reporting detriments to mood, creativity, and energy. The review offers an overview of methods to guide future research.

Study at a glance

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.