Introduction There has been a steep rise in the use of drugs during sex by some men who have sex with men (MSM), with associated increases in sexual risk for HIV and other STIs. This ‘Chemsex’ has been described, but there is a lack of theoretical perspectives applied to this particular phenomenon.

We aimed to assess participants’ reasoning and conceptualisation of Chemsex and situate this within theoretical frameworks.

Methods This study presents data from telephone interviews with 15 MSM attending sexual health clinics following a risk of HIV and accessing post-exposure prophylaxis (PEP). Interviews were conducted as part of a larger interventional study, which used an adapted version of Motivational Interviewing to explore risk behaviour and support change. We used Framework analysis on interview transcripts in order to understand participants’ perspectives on the use of chemsex.

Results Participants conceptualised their chemsex and HIV risks in their psycho-social context, highlighting the influence of the psycho-socio-cultural challenges of homophobic marginalisation and the ‘gay scene’ on their behaviour. Narratives of loneliness and difficulties in forming satisfying social and sexual relationships were repeatedly identified.

Discussion Multiple influences of stigma, minority stress and maladaptive coping (including drug-use) are seen to contribute to syndemic ‘risk-environments’ in which chemsex and risk behaviours are played out. Interventions to address the harms of chemsex must recognise the complex psychosocial context of risk, and shift the responsibility for change from vulnerable individuals to a shared responsibility distributed across social, political and institutional contexts.