Journal of Psychoactive Drugs
November 6, 2024
Rotem Petranker, Valentyn Sobolenko, Zeina Beidas et al.
9 citations
People who exclusively microdose psychedelics differ from those who also take larger doses. Exclusive microdosers are older (average 46.4 vs. 42.0 years), more often female (68.4% vs. 44.7%), non-Caucasian (25.4% vs. 14.7%), and urban residents (43.9% vs. 38.5%). They report using fewer non-psychedelic substances over their lifetime (3.8 vs. 4.7 substances). Most microdose multiple times a month (52.5%), commonly using psilocybin (74.5%), LSD (34.4%), or ketamine (15.8%), and 64.6% do not test their substances. The main reason for microdosing is improving general wellbeing (73.0%).
Journal of Psychoactive Drugs
December 24, 2024
Omer A Syed, Rotem Petranker, Emily C Fewster et al.
3 citations
A strong preference for natural over synthetic sources exists among users of psilocybin (75%), DMT (56%), and mescaline (56%), based on an anonymous online survey of 6,379 consumers from 85 countries. About half of respondents (50.8%) believe the source affects a psychedelic's psychological and physiological effects, while 34.4% are neutral. Despite preferring natural sources, 67.7% would switch to synthetic alternatives if it reduced environmental harm from overharvesting. The survey's respondents came mainly from anglophone regions.
BJPsych Open
February 16, 2026
Zeina Beidas, Anya Ragnhildstveit, Adam Blackman et al.
1 citation
This is a protocol for a phase II trial testing whether very low doses of psilocybin (2 mg, a microdose) can safely and effectively treat major depressive disorder. Forty adults with MDD will receive either psilocybin or a placebo once weekly for four weeks, then all will receive psilocybin for another four weeks. The trial will measure changes in depression symptoms, mood, well-being, attention, creativity, mindfulness, and pro-sociality. Results will be published regardless of outcome. The findings are expected to guide future research on dose regimens, effect sizes, and the role of expectancy bias, and to inform debates about sub-threshold versus threshold doses of psilocybin.
BJPsych Open
May 13, 2026
Zeina Beidas, Anya Ragnhildstveit, Adam Blackman et al.
This is a correction notice for a previously published study protocol. The original protocol describes a phase II double-blind placebo-controlled randomised partial crossover trial investigating microdosing psilocybin for major depressive disorder. No new findings or data are presented.
November 16, 2025
Zeina Beidas, Anya Ragnhildstveit, Adam Blackman et al.
preprint
A phase II trial will test whether microdosing psilocybin (2 mg weekly) outperforms placebo for major depressive disorder. Forty adults will receive either psilocybin or placebo for four weeks, then all will receive psilocybin for another four weeks. Depression symptoms and other measures will be assessed at baseline, after four weeks, and after eight weeks, with follow-ups for two years. The study aims to clarify whether microdosing has genuine antidepressant effects or whether benefits are due to expectancy, and to inform future dose regimens and the therapeutic role of sub-threshold versus threshold doses.