Doxy-PEP stands for doxycycline post-exposure prophylaxis.
It involves taking doxycycline after condomless oral, vaginal or anal sex to prevent syphilis, chlamydia, and possibly gonorrhea.
Who can be considered for Doxy-PEP?
Doxy-PEP has been mostly studied for use in cisgender gay, bisexual and other men who have sex with men (GBMSM) and transgender women (TGW) at higher risk of bacterial sexually transmitted infection (STI).
Factors that can increase the risk of bacterial STI include:
a recent STI
having 10 or more sexual partners in the last 6 months
condomless sex with multiple partners
engaging in group sex
using stimulants during sex (“chemsex”)
How is Doxy-PEP administered?
200 mg of doxycycline taken orally, within 72 hours after condomless oral, vaginal or anal sex.
No more than 1 dose (200 mg) of Doxy-PEP in a 24-hour period.
If condomless sex occurs multiple times within 72 hours: consider 1 dose (200 mg) at the end of the 72 hour period instead of more than 1 dose.
What does the Public Health Agency of Canada (PHAC) recommend?
Informed by the existing scientific evidence, PHAC recommends that health care professionals:
Consider off-label use of Doxy-PEP for cisgender GBMSM and TGW at increased risk of bacterial STI to prevent syphilis, chlamydia, and possibly gonorrhea.
Discuss the potential antimicrobial resistance (AMR) risks with patients considering Doxy-PEP use.
Note: These recommendations do not supersede any provincial/territorial legislative, regulatory, policy and practice requirements or professional guidelines that govern the practice of health professionals in their respective jurisdictions, whose recommendations may differ due to local epidemiology or context.
Reassess the need for Doxy-PEP every 3-6 months, as a person’s risk can change.
Follow PHAC recommendations for STI screening, testing and management, including:
Screen for syphilis, chlamydia and gonorrhea as often as every 3 months.
Collect specimens for gonorrhea culture as indicated, including when testing anyone with symptoms or a sexual contact of someone with gonorrhea. If possible, when a gonorrhea infection was detected using nucleic acid amplification testing only, collect a specimen for gonorrhea culture prior to treatment.
What is known About Doxy-PEP and antimicrobial resistance (AMR)?
Evidence is emerging about the impacts of Doxy-PEP use on AMR. The extent and clinical significance of these effects are uncertain.
Doxy-PEP use is likely to increase doxycycline resistance in gonorrhea and may increase multidrug resistance (MDR) in gonorrhea.
Doxy-PEP use may increase doxycycline resistance and MDR in other bacteria (e.g., Staphylococcus aureus, Shigella spp).
Doxy-PEP and gonorrhea
In Canada, levels of doxycycline resistance in gonorrhea are high, especially among GBMSM. As a result, Doxy-PEP may not be very effective for preventing gonorrhea in Canada.
By exerting selective pressure that favours antibiotic-resistant strains, Doxy-PEP use is expected to increase doxycycline resistance in gonorrhea. This means that any initial protection may be lost.
Selective pressure may also favour strains with co-resistance to doxycycline and other antibiotics, including those recommended for gonorrhea treatment (e.g., cephalosporins). This may lead to increasing MDR in gonorrhea and make treatment more challenging.
