Doxycycline Post-Exposure Prophylaxis (DoxyPEP) for Bacterial STI Prevention
Doxycycline post-exposure prophylaxis (DoxyPEP) is recommended for high-risk populations, including cisgender men who have sex with men and transgender women, as a 200 mg single dose taken within 72 hours after condomless sex to prevent bacterial sexually transmitted infections. 1
Indications and Effectiveness
DoxyPEP is specifically indicated for:
- Prevention of bacterial STIs in high-risk populations
- Particularly effective against:
It's important to note that the FDA label for doxycycline does not specifically list post-exposure prophylaxis for STIs as an approved indication 3. However, current clinical guidelines support this use based on strong evidence from randomized controlled trials.
Recommended Dosing Regimen
- Dose: 200 mg doxycycline as a single dose
- Timing: Within 72 hours after condomless sex
- Maximum: 200 mg per 24-hour period
- Supply: Typically prescribed with 30 doses (60 tablets/capsules) at a time 1
Target Population
DoxyPEP has been primarily studied and is recommended for:
- Cisgender men who have sex with men (MSM)
- Transgender women
- Individuals at high risk for bacterial STIs 1, 4
The evidence base is currently limited for cisgender women and other populations, which represents an important gap in current research 2.
Administration Guidelines
When taking doxycycline:
- Take with food and plenty of fluid
- Remain upright for at least 1 hour after taking
- Separate from dairy products, antacids, and supplements containing calcium, iron, magnesium, or sodium bicarbonate by at least 2 hours 1
Monitoring and Follow-up
For individuals using DoxyPEP:
- Baseline STI testing is recommended at initiation
- Regular STI screening every 3 months at anatomic sites of exposure
- Blood testing for syphilis quarterly
- Reassess the ongoing need for DoxyPEP every 3-6 months 1
Potential Side Effects
Common side effects include:
- Photosensitivity (increased sensitivity to sunlight)
- Esophagitis
- Gastrointestinal intolerance 1
Important Considerations and Limitations
DoxyPEP should be part of a comprehensive sexual health approach that includes:
- Regular STI screening
- Risk reduction counseling
- Condom use
- Appropriate vaccinations (hepatitis B, HPV)
- HIV PrEP when indicated 1
While effective, DoxyPEP is not a "golden bullet" but rather a bridge to more comprehensive STI prevention tools 2
Concerns about antimicrobial resistance need to be weighed against the benefits of STI prevention 2, 4
The most efficient prescribing strategies may target individuals with a history of STIs, particularly those with concurrent or repeated infections 5
DoxyPEP represents an important tool in the prevention of bacterial STIs, particularly in high-risk populations, but should be implemented as part of a comprehensive approach to sexual health.