LAUSR

ISSUES Serotonergic psychedelics (SP) are psychoactive substances that produce unique sets of subjective effects, such as hallucinatory experiences. This systematic review is the first to summarise which motives for SP use have been assessed in medical, psychological, sociological and ethnological research across different types of SPs and across cultural backgrounds. Findings on use motives can be especially important in the context of harm reduction. APPROACH We searched academic databases (Medline, Web of Science and Embase) and included publications if they were peer-reviewed and written in English, German, Spanish or Dutch. We analysed which type of motives were reported, comparing motives from quantitative and qualitative reports, and investigating associations between motives and year of publication, specific SPs and specific participant populations. KEY FINDINGS Our search in November 2020 resulted in 30,257 unique articles of which 37 were included in the analysis. Across all studies, the most common motive for SP use was the desire to expand awareness (78% of included studies), followed by coping (67%) and enhancement (57%) motives. There were no statistically significant associations between reported motive and type of report (quantitative vs. qualitative), year of publication (range: 1967-2020), type of SP and participant population. IMPLICATIONS If SP-related harms are to be reduced, harm-reduction services could focus on providing non-pharmacological ways of fulfilling an expansion motive. Additionally, future studies should aim to assess specific motives for specific SPs. CONCLUSIONS SPs are most commonly used to expand (self-)knowledge, promote spiritual development or for curiosity, notably across different SP user populations including patients.