DoxyPEP (Doxycycline Post-Exposure Prophylaxis)

What is DoxyPEP?

DoxyPEP (doxycycline post-exposure prophylaxis) is the use of a single 200 mg oral dose of doxycycline, taken within 24 - 72 hours after condomless sex, to reduce the risk of acquiring bacterial sexually transmitted infections - principally chlamydia and syphilis, and to a partial degree gonorrhoea.

It is not a treatment for active infection, and it does not prevent HIV. For HIV prevention, HIV PrEP (ongoing) or HIV PEP (within 72 hours of exposure) remain the appropriate tools.

Who DoxyPEP is for - and who it is not for

DoxyPEP is currently recommended for:

• Men who have sex with men (MSM) with a bacterial STI in the past 12 months, multiple recent partners, or other markers of ongoing exposure.
• Transgender women with similar exposure patterns.

DoxyPEP is not recommended - and Hisential does not prescribe it - for:

• Cisgender heterosexual women. The dPEP-Kenya randomised trial (2023) found no statistically significant reduction in bacterial STIs in this group. Possible reasons include lower doxycycline tissue concentrations in the cervix, anatomical differences in exposure, and adherence patterns.
• Cisgender heterosexual men. There is currently no efficacy data from randomised trials in this group, so DoxyPEP cannot be offered as evidence-based prevention.

We will discuss alternatives - barrier methods, regular STI testing, and prompt treatment when indicated - openly and without judgment.

What the evidence shows

Three landmark randomised trials underpin current DoxyPEP guidance:

• DoxyPEP (San Francisco / Seattle, 2023). ~65% reduction in chlamydia, syphilis, and gonorrhoea combined in MSM and transgender women on HIV PrEP or living with HIV.
• DOXYVAC (France, 2023). Similar protection in MSM on PrEP, with the largest effect against chlamydia and syphilis.
• ANRS 174 / IPERGAY sub-study. Earlier signal of efficacy that prompted the wider research programme.
• dPEP-Kenya (2023). Conducted in cisgender women - no significant benefit, the basis for current restriction of the indication.

Together, these trials produce a typical effect size of 70 - 90% reduction in chlamydia and syphilis in eligible populations, with a more modest and locally variable effect against gonorrhoea.

How DoxyPEP is delivered at Hisential

1. Eligibility consultation. A confidential conversation about your sexual health history, current prevention strategy (PrEP, condoms, partner-based), and recent STI testing. We confirm whether DoxyPEP is the right tool for your situation.
2. Baseline workup. Where indicated: HIV, syphilis, chlamydia and gonorrhoea (all relevant sites), plus a brief medication-interaction review.
3. Prescription with clear instructions. A supply of doxycycline 200 mg for on-demand use, with written guidance: take within 24 hours of condomless sex (no later than 72 hours), with water, upright for 30 minutes, and not more than 200 mg in any 24-hour window.
4. Follow-up and quarterly STI screening. Reviewed alongside any existing PrEP follow-up, with honest discussion of antimicrobial resistance considerations and whether continuation is still appropriate.

Side effects and what to watch for

Doxycycline is one of the better-tolerated antibiotics, but you should know:

• Photosensitivity - use sunscreen, especially in Malaysia's sun. This is the most common practical issue.
• Gastrointestinal upset - nausea or discomfort, usually mild. Take with water and food where possible.
• Oesophageal irritation - take with a full glass of water and remain upright for at least 30 minutes.
• Yeast infections - uncommon with intermittent dosing but possible.

Stop and contact us if you develop severe rash, persistent vomiting, or signs of an allergic reaction.

Antimicrobial resistance - the honest trade-off

DoxyPEP is an effective intervention, but it is not without ecological cost. Repeated doxycycline exposure can:

• Select for tetracycline-resistant gonorrhoea, which is already rising in some surveillance datasets.
• Pressure the gut and skin microbiome, with effects that are still being studied.
• Theoretically affect other doxycycline-treatable infections in the wider community.

This is why we limit prescribing to the evidence-supported indication, screen regularly for STIs, and review at each follow-up whether DoxyPEP is still the right tool for you - rather than continuing it indefinitely on autopilot.

How DoxyPEP fits with HIV PrEP and HIV PEP

• HIV PrEP prevents HIV; DoxyPEP prevents bacterial STIs. The two are complementary and commonly used together by MSM and transgender women.
• HIV PEP is for emergencies - a possible HIV exposure in the past 72 hours - and must be started as soon as possible. DoxyPEP is not a substitute for PEP.
• Quarterly STI testing (HIV, syphilis, chlamydia, gonorrhoea at all relevant sites) remains the backbone of any sexual-health prevention plan, with or without DoxyPEP.

Related services

• HIV PrEP - ongoing HIV prevention
• HIV PEP - emergency 72-hour HIV prevention
• STD testing - confidential quarterly screening
• STD treatment - same-day, discreet care

Book a DoxyPEP consultation

Hisential Clinic Bangsar - Lot S122, 2nd Floor, Bangsar Shopping Centre, 285 Jalan Maarof, 59000 Kuala Lumpur. Open 10:00 AM - 8:00 PM daily.

Message your personal concierge: /book-appointment · WhatsApp: +60 12-841 3969 · Call: +60 3-8603 7220

The information on this page is for general educational purposes and does not constitute medical advice. DoxyPEP eligibility and dosing are determined on a case-by-case basis after clinical assessment. KKLIU 0640 / EXP 31.12.2026.