Recent clinical trials show that doxycycline post-exposure prophylaxis (doxyPEP) is efficacious in preventing certain sexually transmitted infections (STI) in gay, bisexual and other men who have sex with men (gbMSM) and transgender women (TGW) with a recent history of bacterial STI (i.e. in the previous year). Further, in many jurisdictions including here in BC, doxycycline is now being provided to some patients for STI prevention. Although there is strong evidence to support the use of doxyPEP to prevent STIs in these populations, it remains unclear what potential impacts this intervention will have at a broader scale, particularly around issues of antimicrobial resistance and impacts on the microbiome.
DoxyPEP has the potential to benefit the health of gbMSM/TGW through STI prevention, lessened patient anxiety, and improved sexual health and well-being. The use of doxyPEP for STI prevention should be a discussion between patient and provider, covering all of the benefits and potential unknowns, using shared decision-making, and consulting with STI experts as necessary. Despite the unanswered questions, doxyPEP should not be withheld from gbMSM/TGW if it is expected to provide a clear benefit. All efforts should be made to make access to doxyPEP as timely and as easy as possible. At this time, there is no data supporting use of doxycycline for STI prevention in non-gbMSM/TGW populations, and no data in non-adult populations. More specifically, there is data from one study in cisgender women demonstrating no doxyPEP benefit, likely owing to poor adherence.
DoxyPEP should be implemented as part of comprehensive sexual health services, including regular (q3 month) STI screening, and HIV pre-exposure prophylaxis (PrEP)/HIV treatment when relevant. When prescribed as doxyPEP, doxycycline should be used as two, 100mg tablets taken within 72 hours after condomless sex, and a supply of 100 mg tablets (with refills) can be provided to eligible patients.