Doxy PEP in Malaysia: how doxycycline after sex helps prevent STIs

Doxy PEP is a newer way to prevent some bacterial sexually transmitted infections (STIs). It means taking one dose of the antibiotic doxycycline after condomless sex. Together with HIV PrEP and condoms, it is now part of sexual health care for people at higher risk in many countries.

In short: take doxycycline 200 mg as a single dose, ideally within 24 hours and no later than 72 hours after condomless oral, anal or vaginal sex. In studies of gay and bisexual men and transgender women, it cut syphilis and chlamydia by about three quarters and gonorrhoea by about half. It does not protect against HIV, so it is used alongside PrEP.

What is Doxy PEP?

PEP stands for post-exposure prophylaxis: medicine taken after a possible exposure to stop an infection taking hold. Doxy PEP uses doxycycline, a long-established antibiotic, against bacterial STIs. It is different from HIV PEP, which is a 28-day course of HIV medicines (see PrEP vs PEP).

How well does it work?

• The DoxyPEP study in the United States found that among gay and bisexual men and transgender women taking HIV PrEP or living with HIV, Doxy PEP reduced the combined number of syphilis, chlamydia and gonorrhoea infections by about two thirds.
• Protection was highest for syphilis and chlamydia (around 70 to 80% fewer), and lower for gonorrhoea, because many gonorrhoea strains are already resistant to doxycycline.
• A study in cisgender women in Kenya did not show a benefit, so current evidence supports Doxy PEP mainly for men who have sex with men and transgender women.

Who is Doxy PEP for?

The US CDC recommends offering Doxy PEP to gay and bisexual men and transgender women who have had a bacterial STI in the past 12 months. Many doctors also consider it for people with frequent condomless sex with new partners, including when travelling. Your doctor will talk through your risk and whether it makes sense for you.

How to take it

1. Take 200 mg of doxycycline (usually two 100 mg tablets) as one dose.
2. Take it as soon as possible, ideally within 24 hours and no later than 72 hours after sex.
3. Take no more than 200 mg in 24 hours, even if you have sex again. One dose covers sex in the previous 72 hours.
4. Swallow with a full glass of water and stay upright for at least 30 minutes, to avoid throat irritation. Take it with food if it upsets your stomach.
5. Avoid milk, antacids, calcium and iron supplements within 2 hours, as they reduce absorption.

Side effects and safety

• Most people have no problems. Some get nausea or stomach upset.
• Doxycycline makes skin more sensitive to sunlight, so use sunscreen, especially in Malaysia.
• Do not use it if you are pregnant or allergic to tetracycline antibiotics.

What about antibiotic resistance?

This is the main concern with Doxy PEP. Using antibiotics more often can encourage resistant bacteria, particularly gonorrhoea and staphylococcus, and may affect gut bacteria. That is why it is offered to people who will benefit most, used only after actual exposures, and combined with regular STI testing every 3 months, so infections that get through are treated properly.

Doxy PEP, PrEP and testing work together

Doxy PEP does not prevent HIV, herpes, HPV or hepatitis. Combine it with HIV PrEP, condoms, the HPV and hepatitis B vaccines, and regular testing for HIV, syphilis, chlamydia and gonorrhoea.

Getting Doxy PEP in Malaysia

Doxycycline is a prescription medicine in Malaysia. At CarePlus Clinic our doctor reviews your health and sexual health history, then supplies it with clear instructions. Our Travel Sexual Health Kit contains 10 Doxy PEP tablets and 10 PrEP tablets, with a refill pack when you need more. Read our travel sexual health guide before a trip, or WhatsApp us on +60 11-2615 1500 in confidence.