Overdose risk in the context of chemsex among gay, bisexual, and other men who have sex with men.

Chemsex is defined as the use of psychoactive substances - most commonly methamphetamine, synthetic cathinones, and Gamma-hydroxybutyrate/Gamma butyrolactone (GHB/GBL) - to enhance sexual activity primarily among gay, bisexual, and other men who have sex with men (GBM). It is associated with higher rates of sexually transmitted infections, HIV, and mental health conditions. However, despite substantial public health concerns regarding rising overdose deaths, the relationship between chemsex and overdose remains poorly studied. In this perspective, we synthesize the current evidence, identify critical knowledge gaps regarding the association between chemsex and overdose risk among GBM, and outline harm reduction and behavioral interventions. Assessing chemsex-related overdose deaths among GBM is challenging due to the limited documentation of sexual practices and sexual orientation in medical or legal records. Stigma further reduces disclosure, and chemsex involvement is rarely identifiable posthumously. Chemsex frequency and perceptions of harm also obscure problematic use. Effective pharmacologic treatments for stimulant dependence remain limited. In contrast, contingency management (CM) has been proven effective in reducing stimulant use, yet remains underutilized. Integrated harm reduction approaches are essential to mitigate the potential risks of chemsex. Key interventions include HIV testing, needle exchange, sexual health screenings, psychosocial interventions, and vaccinations. There is an urgent need for targeted research, improved data collection, and tailored harm reduction strategies to better understand and reduce overdose risk within chemsex contexts. Addressing these gaps is essential for reducing preventable deaths and improving health outcomes in this population.