Chemsex involves using drugs like methamphetamine, ketamine, or “poppers” to intensify sexual encounters. This practice significantly increases the risk of HIV transmission, especially for those who inject substances. Health data shows these individuals face a risk about 14 times higher than the general adult population. In Brazil, studies indicate chemsex prevalence among men who have sex with men ranges from 27% to nearly 70%. Despite these risks, organized health responses remain uncommon in many regions.
São Paulo’s party-based outreach
A six-month pilot in São Paulo partnered a local NGO, Centro de Convivência É de Lei, with municipal and state governments to reach approximately 3,000 people at seven chemsex parties. The initiative distributed 6,000 units of lubricant, 2,000 condoms, 300 combined prevention kits, and 200 HIV self-test kits. It also included a workshop for health professionals and public managers.
Eduardo Almeida, a co-author of the study, explained the pilot depended on coordinated efforts between civil society and public institutions to access these environments and maintain care. This was among the first initiatives in Latin America to view chemsex parties as opportunities for public health intervention rather than targets for law enforcement.
Bangkok’s transgender-focused cohort
Thailand’s iT-REX study, presented by Akarin Hiransuthikul, involved 63 transgender women who use substances or engage in chemsex. Participants, with a median age of 31, underwent assessments covering substance use, sexual health, mental health, and socio-legal issues. Over half screened positive for mental health concerns, and nearly 70% reported experiencing stigma or discrimination, though few sought help for these issues.
Still, 69.8% of participants agreed to start or continue PrEP. More than half of those using hormones also requested hormone-level testing, a service rarely included in chemsex programs elsewhere. The study was conducted by the Institute of HIV Research and Innovation.
A 15-month pilot in South Africa, funded by the Elton John AIDS Foundation, targeted men who have sex with men in Soweto, Orange Farm, and Johannesburg’s inner city. The program, presented by Dawie Nel of OUT LGBT Well-Being, combined harm reduction, group cognitive behavioral therapy, peer navigation, and outreach to eight chemsex houses. Among the 127 HIV-positive participants enrolled, 69% received new diagnoses. By the program’s conclusion, viral suppression reached 88%, and harmful drug use declined from 79% to 57%.
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Improvements were also noted in anxiety, depression, psychosis, internalized homophobia, and suicidal ideation. Retention dropped to 67% by the program’s close, which included a no-cost extension through September 2025.
The majority of programs discussed at the conference relied on collaborations between NGOs and public health agencies. This model has proven effective in other HIV prevention efforts but remains relatively new for chemsex. Presenters emphasized the difficulty of scaling these initiatives without losing the trust of communities that have historically been overlooked or targeted by authorities.
Access to essential health services remains limited for many affected by chemsex.
