Prevention

DoxyPEP

What you need to know

DoxyPEP (doxycycline post-exposure prophylaxis) is an antibiotic taken after sex that can help prevent some sexually transmitted infections (STIs).

Research has shown that DoxyPEP can significantly reduce the chance of getting syphilis and chlamydia, although it is not 100% effective. In Ireland, it is unlikely to prevent gonorrhoea because many gonorrhoea infections are resistant to doxycycline. DoxyPEP does not protect against HIV.

DoxyPEP can be a part of looking after your sexual health. Regular STI testing, HIV PrEP, HIV PEP, vaccination and condoms all continue to play an important role.

Is DoxyPEP be right for me?

In Ireland, DoxyPEP may be offered to gay, bisexual and other men who have sex with men (gbMSM) and trans women who have sex with men who are at increased risk of syphilis.

This may include people who:

  • have had a bacterial STI in the last 12 months
  • have multiple or new sexual partners
  • have occasional or one-off partners
  • take part in group sex or chemsex

Everyone's circumstances are different. A healthcare professional can discuss whether DoxyPEP is appropriate for you based on your sexual health, medical history and individual needs.

How do I get DoxyPEP?

If you think DoxyPEP could benefit you, speak to your local sexual health service.

They can:

  • answer your questions
  • discuss whether DoxyPEP is suitable for you
  • explain how to take it correctly
  • prescribe it if appropriate
  • arrange any follow-up care you may need

In Ireland, doxycycline is a prescription-only medicine. If you access DoxyPEP through your sexual health service, you'll be given a prescription to take to your community pharmacy. The medication is dispensed by the pharmacy, and you'll need to pay for it. When attending your sexual health service you'll also receive advice, ongoing support, and regular sexual health check-ups.

How do I take DoxyPEP?

If you're prescribed DoxyPEP, the recommended dose is:

200mg doxycycline (two 100mg tablets)

Take it:

  • as soon as possible after condomless oral or anal sex
  • ideally within 24 hours
  • no later than 72 hours
  • no more than once in any 24-hour period

If you have sex more than once over a short period, your healthcare provider will advise you on the best way to take DoxyPEP to reduce the amount of antibiotics you take.

Are there any side effects?

Most people tolerate doxycycline well.

Possible side effects include:

  • headache
  • nausea
  • vomiting
  • acid reflux
  • increased sensitivity to sunlight, which can cause a photosensitivity rash

To help reduce side effects:

  • take DoxyPEP with a full glass of water
  • avoid lying down for 30 minutes after taking it
  • use sunscreen and avoid prolonged sun exposure while taking doxycycline

Doxycycline can also interact with some medicines and supplements. Tell your healthcare provider about any medicines or supplements you're taking before starting DoxyPEP.

While taking DoxyPEP

DoxyPEP works best as part of your overall sexual health.

It's still important to:

Your healthcare provider will also review whether DoxyPEP continues to be appropriate for you over time.

Frequently Asked Questions

DoxyPEP stands for doxycycline post-exposure prophylaxis. It involves taking the antibiotic doxycycline after sex to help prevent some bacterial STIs.

Research shows DoxyPEP can help prevent syphilis and chlamydia. It is unlikely to prevent gonorrhoea in Ireland because many gonorrhoea infections are resistant to doxycycline.

No. DoxyPEP does not protect against HIV. If you're worried about HIV after sex, find out about HIV PrEP and HIV PEP.

Studies have shown DoxyPEP can reduce the chance of getting syphilis and chlamydia by around 80%, it is not 100% effective.

In Ireland, DoxyPEP may be offered to gbMSM and trans women who have sex with men who are considered to be at increased risk of syphilis. Your healthcare provider will discuss whether it's suitable for you.

Speak to your local sexual health service. They can advise whether DoxyPEP is appropriate for you and prescribe it if needed.

Take 200mg (two 100mg tablets) as soon as possible after condomless oral or anal sex, ideally within 24 hours and no later than 72 hours afterwards.

You should not take more than one 200mg dose in any 24-hour period. If you have sex more than once over a short period, your healthcare provider can advise you on the best dosing schedule.

Doxycycline is a prescription-only medicine in Ireland. If you're thinking about using DoxyPEP, your sexual health service can provide advice, prescribe it if appropriate and support you with ongoing care.

Possible side effects include headache, nausea, vomiting, acid reflux and increased sensitivity to sunlight which can result in a rash. Most people tolerate doxycycline well.

To help reduce side effects:

  • take DoxyPEP with a full glass of water
  • avoid lying down for 30 minutes after taking it
  • use sunscreen and avoid prolonged sun exposure while taking doxycycline

Yes. Regular STI testing remains important while taking DoxyPEP, even if you don't have symptoms. Your healthcare provider will discuss how often you should be tested.

Yes. HIV PrEP and DoxyPEP protect against different infections and can be used together.

Contact your sexual health service as soon as possible for advice, testing and treatment. If you have symptoms of an STI, it's best to avoid sex until you've been assessed.

No. DoxyPEP isn't suitable for everyone. Your healthcare provider will discuss whether it's appropriate for you, taking into account your medical history, current medicines and individual circumstances.

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