Appropriate use of Doxy-PEP and inappropriate antibiotic self-medication for STI management: insights from a LGBTQIA+ survey in Italy

Doxycycline post-exposure prophylaxis (Doxy-PEP) has emerged as a promising strategy for preventing selected bacterial sexually transmitted infections (STIs). Nevertheless, concerns remain regarding unsupervised access and inappropriate antibiotic use, particularly in populations disproportionately affected by STIs. In Italy, evidence on real-life Doxy-PEP use and antibiotic self-medication for STI management is still limited. We conducted a nationwide cross-sectional survey among LGBTQIA+ individuals in Italy to estimate the prevalence of Doxy-PEP use and antibiotic self-medication involving antibiotics other than doxycycline, and to identify associated determinants. Data were collected through an anonymous, online questionnaire disseminated via community-based channels. Among 211 respondents, 21.3% reported Doxy-PEP use, while 11.1% antibiotic self-medication for STI management. Doxy-PEP use was associated with HIV PrEP use (OR = 6.10; 95% CI: 1.09–34.24) and at least one STI diagnosis in the previous 12 months (OR = 6.33; 95% CI: 1.72–23.41), whereas it was inversely associated with antibiotic self-medication (OR = 0.04; 95% CI: 0.00–0.56). Antibiotic self-medication was associated with a history of prior STIs (OR = 4.82; 95% CI: 1.27–18.37) and younger age (OR = 0.93 for year; 95% CI: 0.86–0.99). A non-negligible proportion of Doxy-PEP users obtained doxycycline through informal or non-prescribed channels. Two distinct patterns of antibiotic exposure coexist within the Italian LGBTQIA+ community: structured Doxy-PEP use embedded in prevention pathways and unsupervised antibiotic self-medication. Integrated strategies are needed to support appropriate Doxy-PEP implementation, reinforce antimicrobial stewardship, and reduce barriers to equitable sexual health care. • This survey provides the first Italian evidence distinguishing guideline-consistent Doxy-PEP use from inappropriate antibiotic self-medication for STI prevention and management within the LGBTQIA+ community. • Doxy-PEP use was strongly associated with engagement in formal sexual health pathways, including HIV PrEP use and recent STI diagnoses, supporting its role as a structured secondary prevention strategy. • Antibiotic self-medication emerged as a distinct and unsupervised practice, more common among younger individuals and those with prior STIs. • High willingness to use Doxy-PEP if medically prescribed highlights a substantial unmet demand, likely constrained by limited clinical guidance and access rather than individual reluctance. • Integrated public health strategies are needed to promote appropriate Doxy-PEP implementation, strengthen antimicrobial stewardship, and reduce informal antibiotic use outside medical oversight.