Participant Experiences of Microdosed Lysergic Acid Diethylamide in a 6-Week Randomised Controlled Trial

The article begins by outlining the growing interest in microdosing psychedelics, a practice in which people take very small, sub-hallucinogenic doses of a substance such as LSD on a regular schedule. Individuals often report that microdosing enhances emotional wellbeing, creativity, focus, or social engagement. However, most of what is known about microdosing comes from online accounts or informal community reports, which makes it difficult to determine whether the effects attributed to microdosing are due to the drug itself or to expectation, placebo, or inaccurate dosing. Murphy and colleagues note that although several controlled trials have recently been conducted, none has previously published qualitative data about participants’ lived experiences. This study therefore aims to provide such insight within the structure of a fully randomised, placebo-controlled trial.

The authors explain that microdoses are often described as “sub-perceptual”, but people who microdose do sometimes notice subtle shifts in perception or emotion. Because these changes do not resemble the intense, immersive effects of a full psychedelic dose—such as pronounced visual imagery or dramatic changes in consciousness—the term sub-hallucinogenic is used instead. Earlier research has suggested that microdosers commonly seek improvements in mood, productivity, or emotional regulation, but negative effects—particularly overstimulation and anxiety—have also been reported. Another key issue raised in the introduction is the importance of set and setting, meaning a person’s mindset and their environment. These factors are known to shape full-dose psychedelic experiences, but they have rarely been examined in microdosing research. The present study therefore investigates not only the effects participants attributed to LSD microdoses but also the environmental and psychological influences that shaped those experiences.

Methods

Methodology and Positionality

The qualitative data analysed here were drawn from 40 participants who received LSD in the larger MDLSD randomised controlled trial. Participants were healthy adult males who took 10 micrograms of LSD every third day for six weeks, following a widely used microdosing schedule. They completed a baseline session and one supervised dose at the research clinic before taking the remaining doses at home. Interviews were conducted two days after the final microdose. Murphy and colleagues chose content analysis as their qualitative approach because the relatively large sample size allowed for systematic coding and the identification of patterns across many participants.