Participant Experiences of Microdosed Lysergic Acid Diethylamide in a 6-Week Randomised Controlled Trial
Robin J Murphy, Mia Wardlaw, Thomas A. Smith, Tehseen Noorani, William Evans, Lisa Reynolds, David B Menkes, Rachael Sumner, Suresh Muthukumaraswamy
Journal of Humanistic Psychology November 10, 2025 DOI: 10.1177/00221678251382624 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Randomized controlled trial Placebo-controlled Double-blind Qualitative Peer reviewed |
|---|---|
| Sample size | 40 |
| Population | Healthy males |
| Intervention | Lysergic acid diethylamide |
| Dose | 10 µg |
| Duration | Every third day for 6 weeks |
| Topics | Anxiety LSD Psilocybin |
| Keywords | Mood Context archaeology Randomized controlled trial Relevance law Qualitative research Openness to experience Clinical psychology Psychotherapist Hallucinogen Qualitative property Clinical trial Qualitative analysis Perception Research design |
| Key findings | Microdosing with 10 µg of LSD every third day for six weeks produced a range of subjective effects spanning emotions, social life, cognition, and physiology, with openness to experience and bidirectionality of effects as overarching themes. |
Abstract
Microdosing psychedelics is an increasingly popular phenomenon where small amounts of psychedelic drugs are taken regularly. Qualitative data have been published regarding the experiences of microdosers, but never in the context of a randomised controlled trial. Semi-structured video interviews with 40 healthy males were conducted following a double-blind placebo-controlled trial of 10 µg of lysergic acid diethylamide every third day for 6 weeks. Data were analysed using content analysis with initial deductive categories derived from the literature populated with inductively derived codes. Drug effects were classified in the following categories: “emotions and mood,” “social life,” “mindfulness,” “cognition, work, and creativity,” and “physiological effects,” with an additional “influences” code for non-drug modifiers of participants experiences in the trial. Themes which spanned these categories were openness to experiences and a bidirectionality of effects. Some identified codes have potential clinical relevance and may support the use of microdosing in treatment of mood disorders. Reports of changes in anxiety suggest important considerations in selecting appropriate patients and doses. Of relevance to psychedelic clinical trial design are participants’ reports regarding set and setting, the uncertainty caused by participating in a placebo-controlled trial, and perceived bidirectionality of effects.