DoxyPEP, short for doxycycline post-exposure prophylaxis, is a preventive medical strategy that involves taking a single dose of the antibiotic doxycycline within 72 hours after condomless sex to reduce the risk of acquiring certain bacterial sexually transmitted infections (STIs). Specifically, it has shown effectiveness against syphilis and chlamydia, with more modest results for gonorrhea, depending on regional antibiotic resistance patterns.
DoxyPEP is particularly recommended for:
DoxyPEP is not a substitute for regular STI testing, condom use, or HIV prevention strategies like PrEP. Instead, it’s an additional layer of protection for those at elevated risk. As with any antibiotic-based intervention, concerns about antimicrobial resistance are being closely monitored, and ongoing research continues to refine its use.
If you think DoxyPEP might be right for you book an appointment to discuss.
There’s no solid evidence that other antibiotics offer similar protection. Misusing antibiotics can be harmful and may lead to serious side effects or antibiotic resistance.
Studies have mainly shown DoxyPEP to be effective for people assigned male at birth who have sex with other men, including:
There’s currently not enough research to recommend DoxyPEP for those engaging in vaginal/frontal sex (e.g., cisgender women, transgender men). However, anyone who feels they may benefit should consult a sexual health provider.
Doxycycline is not recommended for those who are pregnant or breastfeeding.
Antibiotic resistance
Regular use of antibiotics like doxycycline can increase bacterial resistance, which poses a public health concern. Though current studies haven’t shown resistance in chlamydia or syphilis, ongoing monitoring is important. There’s also a concern about resistance to ceftriaxone, commonly used to treat gonorrhoea.
Impact on gut and skin bacteria
Doxycycline may affect natural bacteria in your body, though the long-term effects are still being researched.
Take 200mg (two 100mg pills) of doxycycline as soon as possible after sex—ideally within 24 hours, and no later than 72 hours.
If you have multiple sex partners over a short time (e.g., a weekend), you may take one dose covering that 72-hour period.
One dose per day is the maximum recommended to reduce the chance of side effects.
Take with food and water to avoid nausea.
Don’t lie down for at least 30 minutes after taking it.
Avoid dairy products, antacids, and calcium supplements two hours before/after your dose.
Protect your skin from sunlight (doxycycline can increase sun sensitivity).
DoxyPEP isn’t 100% protective. Keep testing for STIs regularly—at least every 3 months.
See a healthcare provider if you have symptoms—DoxyPEP doesn’t treat active infections.
Always tell your doctor about your medications before starting DoxyPEP. It may interact with:
Doxycycline is generally well-tolerated. Common side effects include:
Do not share prescription medication. Doxycycline must only be taken if prescribed to you. It is illegal and unsafe to obtain it without a prescription in Ireland.
To discuss DoxyPEP book now
prices are subject to change
| *Description* | *Price* |
|---|---|
| DoxyPEP script online | €60 |
*We are not a pharmacy and are unable to fill any DoxyPEP prescriptions.