Chemsex, or “chemical sex”, refers to the deliberate use of psychoactive substances to facilitate, prolong, or intensify sexual practices and is often associated with high-risk dynamics for sexually transmitted infections (STIs). This practice has been increasing among men who have sex with men (MSM), especially in large urban centers such as São Paulo, where drug availability and dating app use are greater. Adverse effects of chemsex include loss of control, social impairment, and increased exposure to unprotected practices. This study aimed to describe the sociodemographic and behavioral profile of MSM who practice chemsex in the Greater São Paulo area. Cross-sectional study with data collected through an anonymous online form, approved by the Research Ethics Committee (CAAE n° 63251122.3.0000.9487). Participants aged 18 years or older were included. A total of 243 responses were analyzed. The mean age was 32 years, with a predominance of cisgender men (approximately 85%) and self-declared White individuals. Most participants reported being single (over 60%) and having completed higher education or postgraduate studies. About 70% reported having heard of chemsex, 44% stated they knew people who use substances for sex, and 39% reported personal use of substances to maintain or intensify sexual activity, mainly marijuana, poppers, Viagra, and ecstasy. Among those who reported use, the main adverse effects included social impairment, anxiety symptoms, and difficulty maintaining daily activities. Approximately 60% of participants did not use any STI prevention method; among those who did, condoms and PrEP were the most frequently cited. The findings reveal a significant presence of chemsex among MSM in São Paulo, associated with the use of multiple substances and low adherence to combined prevention strategies. In an urban context marked by inequalities, chemsex emerges as a practice that exposes social vulnerabilities, exclusion, and institutional invisibility. There is an urgent need to develop care strategies that consider not only biomedical prevention, but also the psychosocial and cultural aspects involved in drug-mediated sexual experiences, as well as strengthening integrated and welcoming public policies.
Leite et al. (Sun,) studied this question.