Doxy-PEP for Bacterial STI Prevention: EU/EEA Public Health Advice

In clinical trials, doxycycline post-exposure prophylaxis (doxy-PEP) - defined as taking a single 200 mg dose of doxycycline within the first 24 hours and no longer that 72 hours after condomless sex - has shown to be effective in reducing chlamydia and syphilis incidence among men who have sex with men and transgender women. It has also shown to be effective in real-world settings when integrated into comprehensive sexual health strategies for individuals at high risk of acquiring an STI. However, research also indicates that doxy-PEP may contribute to the development of antimicrobial resistance in targeted bacterial pathogens and bystander organisms, not only among doxy-PEP users, but also among nonusers, such as those within sexual networks, the wider community of men who have sex with men, and potentially, the broader population. Across the EU/EEA, existing guidelines on doxy-PEP vary. Some authorities recommend its use on a case-by-case basis, primarily for syphilis prevention among men who have sex with men and transgender women at high risk of acquiring an STI, while others advise against it. These differing positions reflect ongoing uncertainty regarding the public health benefits of this prophylactic intervention balanced with its potential harms, particularly the risk of increasing antimicrobial resistance. Regardless of national recommendations, doxy-PEP use is expanding among men who have sex with men in the EU/EEA, both through off-label medical prescription and self-sourcing. The purpose of this document is to support public health actions in countries or regions that are considering doxy-PEP as a component of comprehensive and integrated sexual health and bacterial STI prevention strategies among men who have sex with men and transgender women at high risk of acquiring syphilis.