Chemsex Practice Among PrEP Users in Buenos Aires, Argentina.
AIDS and behavior January 27, 2026 I Pastor, M A Kundro, M Alonso Serena et al.
Among HIV pre-exposure prophylaxis (PrEP) users in Buenos Aires, Argentina, 32% reported engaging in chemsex—the intentional use of psychoactive substances to enhance sexual activity—in the previous year. The most commonly used drugs were MDMA (21%), cocaine (14%), and gamma-hydroxybutyrate (12%); nearly half (48%) used two or more drugs together. Those who practiced chemsex had 3.67 times higher odds of reporting a sexually transmitted infection in the past year, independent of age, time on PrEP, number of sexual partners, or group sex. The findings underscore the need to integrate behavioral assessments and harm reduction into PrEP and sexual health policies.