This online cross-sectional study investigated the intentional use of psychoactive substances to facilitate, enhance, or prolong sexual encounters—commonly termed chemsex—among men who have sex with men (MSM) in Yangon, Myanmar. Chemsex has been associated with higher-risk sexual practices that elevate transmission risk for HIV and other sexually transmitted infections. Prior regional research has documented methamphetamine and GHB/GBL as frequent chemsex substances and linked chemsex to condomless sex, group sex, and injection practices (slamsex). Because chemsex had not previously been studied in Myanmar, this assessment aimed to determine prevalence, characterize practices and settings, document adverse outcomes, and identify factors associated with chemsex among Yangon MSM.
A structured online questionnaire was administered between December 1, 2024 and January 25, 2025. Inclusion criteria were age 18 or older, residence in Yangon, ability to read Burmese, and sexual activity in the preceding six months. Recruitment used social media, private Telegram groups, Facebook pages for Yangon MSM, and dating apps (e.g., Grindr). Data were collected on the KoboCollect platform and exported for analysis in SPSS. The instrument covered sociodemographics, lifestyle and sexual practices, HIV-related characteristics, sexualized drug use, and attitudes toward chemsex. Content validity was assessed by two experts (overall CVI 0.96). Descriptive statistics summarized participant characteristics; bivariate analyses used chi-square testing. Logistic regression with backward stepwise selection identified predictors of chemsex; variables with p < 0.2 in bivariate analysis entered the multivariable model. Ethical approval was obtained from the Ethics Review Committee of the Ministry of Health, National Unity Government, Myanmar (Ethics/NUG-MOH/2024/06). Participation was anonymous and voluntary.
A total of 415 MSM completed the survey. Mean age was 30.1 years (SD 7.1, range 18–56); 71.3% were younger than 35. Sexual orientation self-identification was 76.4% gay and 23.6% bisexual. Educational attainment was high: 62.2% had a bachelor’s degree or higher and 21.4% were current university students. Employment was reported by 59% of respondents, 29.2% were freelance or in business, and 11.8% were unemployed. Monthly income exceeded 600,001 MMK for 51.1% of participants. Regarding HIV status, 14.2% self-reported living with HIV (96.6% of these were on antiretroviral therapy), 71.3% reported HIV-negative status, and 10.1% were unsure. Current pre-exposure prophylaxis (PrEP) use was 29.1%.
Overall, 26.0% (108/415) of participants reported ever engaging in chemsex. Within the six months before the survey, 20.7% reported chemsex; 5.3% reported prior experience but not within that six-month window. The mean age at first chemsex was 26.7 years (SD 6.2, range 15–44).
Among the 108 participants reporting chemsex, methamphetamine was the most commonly used drug (69.8%), followed by poppers (33.7%) and cannabis (19.8%). Routes of administration were predominately injection and inhalation; injection was reported in 67.4% of chemsex users, with 62.1% self-injecting and 67.2% having been injected by others. Sharing of injection equipment was reported less frequently (8.6%). Chemsex sessions most often occurred in hotels (76.7%) and private homes (54.7%). Nearly half of sessions (46.5%) lasted between 4 and 12 hours, while 41.9% lasted under 4 hours.
Sexual risk behaviors during chemsex were notable. Consistent condom use during chemsex in the prior six months was reported by only 10.5% of participants; 52.3% reported sometimes using condoms and 24.4% reported never using condoms. Group sex was reported by 40.7% of chemsex participants; within group sex events, threesomes accounted for 57.1% and groups of 4–5 partners for 40%. Condom use during group sex remained inconsistent: 11.4% always used condoms, 54.3% sometimes, and 22.9% never.
Participants reported multiple adverse outcomes associated with chemsex. Physical discomfort or unpleasant sensations were reported by 52.3%. Mental health or neuropsychiatric symptoms included anxiety or panic attacks (38.4%), paranoia (22.1%), and irritability or aggressive behavior (19.8%). Severe but less common outcomes included overdose with loss of consciousness (3.5%), suicidal thoughts (2.3%), and suicide attempts (2.3%). Medication adherence was affected for some: 10.5% missed regular medications because of chemsex and 30.2% were unsure. Additionally, 30.2% reported using illicit drugs outside sexual contexts.
HIV-related indicators in this cohort showed that 14.2% self-identified as living with HIV and most of those (96.6%) reported being on ART. PrEP use was reported by 29.1% of participants. The observed low rates of consistent condom use during chemsex and the frequency of group sex present elevated risks for HIV and other sexually transmitted infections, although this study reports self-reported status and behaviors rather than biological outcomes.
Multivariable logistic regression identified several factors significantly associated with reporting chemsex. Participants who identified as gay had higher odds of chemsex (adjusted odds ratio [aOR] = 3.0, 95% CI: 1.5–5.9, p = 0.001). Current smoking was associated with higher odds (aOR = 2.8, 95% CI: 1.2–4.0, p = 0.006). Participation in group sex was a strong correlate (aOR = 4.0, 95% CI: 2.4–6.6, p < 0.001), and having multiple sexual partners was also associated (aOR = 3.3, 95% CI: 1.7–6.3, p < 0.001).
The authors emphasize that the measured chemsex prevalence and associated high-risk sexual and drug-use practices represent an urgent public health concern among MSM in Yangon. Recommended responses include targeted education and harm-reduction strategies tailored to MSM, improved access to MSM-specific health services, promotion of regular HIV and STI screening, condom promotion, mental health and substance use services, and facilitated access to prevention tools such as PrEP. The study highlights the need for services that consider the criminalized and stigmatized context in Myanmar, where same-sex sex and drug use face legal and social barriers that may limit help-seeking.
The study used convenience online recruitment and self-reported data, which can introduce selection bias and reporting bias. The sample may overrepresent MSM active on social media and dating apps and those comfortable reporting sensitive behaviors online. Biological outcomes (HIV/STI testing) were not measured; all HIV-related data were self-reported. The authors used a systematic-review prevalence estimate to calculate sample size because no prior Myanmar chemsex data existed.
Chemsex was reported by more than one-quarter of surveyed MSM in Yangon, with frequent use of methamphetamine, predominance of injection routes, extended session duration, common group sex, and low rates of consistent condom use. Chemsex correlated with gay identity, smoking, group sex, and multiple partners. The findings support urgent, tailored harm-reduction, prevention, and clinical services for MSM engaging in chemsex in Yangon.