Sexualised Drug Use and Chemsex: A Hidden Public Health Challenge in Sri Lanka

Sexualised drug use (SDU) refers to the intentional consumption of psychoactive substances before or during sexual activity to enhance sexual experience, reduce inhibitions, or prolong sexual encounters. While extensively documented among men who have sex with men (MSM) in high-income countries, chemsex remains under-recognised and poorly documented in low- and middle-income countries (LMICs), including Sri Lanka. This editorial article provides a narrative overview of SDU and chemsex, synthesising global and regional evidence on associated human immunodeficiency virus (HIV) and sexually transmitted infection (STI) risks, and situating the issue within the Sri Lankan context. Sri Lanka’s youth are at a higher risk of HIV, with MSM disproportionately affected, alongside emerging patterns of synthetic drug use among young adults in urban and nightlife settings. The conjunction of substance use, sexual risk behaviour, stigma, and limited surveillance contributes to a largely hidden public health burden. A brief case illustration of two young men presenting for counselling and STI screening following exposure to a sexualised drug-use environment highlights how chemsex-related contexts can act as an entry point to high-risk sexual behaviour among previously inexperienced individuals. The editorial discusses why chemsex matters for public health, identifies vulnerable populations, and outlines prevention and response strategies, including harm reduction, integration into HIV/STI services, and community-based interventions. Recognising and addressing chemsex is timely and essential for strengthening HIV and STI prevention efforts in Sri Lanka.