Interest, Knowledge, and Use of Doxy-Pep for Prevention of Sexually Transmitted Infections (Stis) Among Sexual and Gender Minorities: Results From an Online Survey in Three Latin American Countries (Brazil, Mexico, and Peru)

STIs are an important public-health issue that disproportionately affects sexual and gender minorities (SGM) in Latin America. Despite doxy-PEP efficacy in preventing syphilis, chlamydia, and gonorrhea, its use remains little studied in the region. This study aimed to estimate interest in, prior knowledge of, and use of doxy-PEP among SGM in Brazil, Mexico, and Peru. Online cross-sectional survey (Aug–Dec/2024) of participants aged ≥ 18 years, recruited via apps and social networks. We included people designated male at birth who identified as cisgender men, travestis, transgender women, or nonbinary/other. Three outcomes were analyzed: interest in, prior knowledge of, and use of doxy-PEP. Multivariable logistic regression identified factors associated with knowledge. Among 15,797 participants (Brazil: 10,119; Mexico: 4,019; Peru: 1,659), interest in doxy-PEP was high (88%), but only 37% reported prior knowledge and 7.2% reported prior use. Knowledge was higher in Mexico (53%), followed by Brazil (33%) and Peru (26%). Greater knowledge was associated with higher education (aOR = 1.21), ≥ 5 partners in the last 6 months (aOR = 1.32), current or prior PrEP use (aOR = 2.76), living with HIV (aOR = 1.83), greater HIV knowledge (per-point aOR = 1.20), and recent stimulant use (aOR = 1.20). Age > 30 years (aOR = 0.88) and higher internalized LGBT-phobia scores (aOR = 0.98) were associated with lower knowledge. Interest in doxy-PEP was greater among younger, non-White people living in capitals, with multiple partners, engaged in transactional sex, using stimulants, on PrEP, or living with HIV. Prior use was more frequent in Mexico (9%) and Peru (8.4%) than in Brazil (6.3%). In Brazil, all users reported medical prescription and, in most cases, adequate adherence. Despite high interest, knowledge and use of doxy-PEP remain low and uneven across countries, reflecting structural barriers and the absence of regional guidelines. Prevention strategies should prioritize accessible information, integration with PrEP services, and community-based approaches to ensure greater equity in the STI response among SGM in Latin America.