Adverse experiences resulting in emergency medical treatment seeking following the use of lysergic acid diethylamide (LSD).

BACKGROUND: Recreational lysergic acid diethylamide (LSD) use is growing in popularity amid increasing research interest on psychedelics and their possible therapeutic potential yet; the potent psychotropic effects of LSD may result in adverse reactions and behaviour.

AIMS: This study aimed to investigate the 12-month incidence and nature of LSD-related adverse experiences resulting in emergency medical treatment (EMT) seeking in an international sample of people reporting LSD use.

METHODS: We use data from the 2017 Global Drug Survey - a large anonymous online survey on patterns of drug use conducted between November 2016 and January 2017.

RESULTS: Out of 10,293 past-year LSD users, 102 (1.0%) reported seeking EMT, with a per-event risk estimate of 0.2%. Younger age, comorbid mental health conditions and higher frequency of use were associated with increased risk of EMT seeking. The most common symptoms were psychological, including anxiety, panic and confusion, with the most common explanatory factors cited by respondents being poor 'setting' and 'mindset'. Most responders reported feeling back to normal within 24 h, but 11 participants experienced persistent issues after 4 weeks.

CONCLUSION: The results suggest that LSD is a relatively safe drug in recreational settings. Adverse reactions are typically short-lived, self-limiting and psychological in nature. Sub-optimal set and setting were commonly reported as suspected contributory factors. Within clinical settings, patient screening, preparatory sessions and supervision should reduce these acute risks considerably.