DoxyPEP

DoxyPEP is where people take an antibiotic, called doxycycline, after sex to reduce their chance of getting syphilis and chlamydia. It is up to 80% effective at preventing syphilis and chlamydia. If you have symptoms you should still attend clinic for testing. It does not work against HIV.

Doxy stands for Doxycycline (an antibiotic)

PEP stands for Post exposure prophylaxis (taken after sex)

Who is DoxyPEP for?

It is recommended for gay, bisexual and other men or trans-women who have sex with men. It may be offered to other people in clinic if they are also at high risk for syphilis infection.

You cannot take doxyPEP if you’re pregnant, or you are allergic to doxycycline.

Doxycycline can interact with other medications. Please do not start doxyPEP until you have discussed your medications with your Doctor or nurse, especially if you are on treatment for acne, epilepsy, take warfarin or take medications that lower the immune system.

How do I take DoxyPEP?

Take 200mg of doxycycline, ideally within 24 hours and no later than 72 hours after sex. (2 tablets of 100mg each)

You should not take more than 200mg of doxycycline within 24 hours.

If you have sex on more than one occasion in a 72-hour period, consider taking 200mg of Doxycycline at the end of 72 hours. This may reduce your side effects, and the number of tablets you need to take.

Side effects include: headache, nausea, vomiting and reflux. Take it with a full glass of water, and do not lie flat for 30 minutes after taking. You should wear high factor sunscreen when it is sunny and avoid sun beds.

Do not take vitamin supplements or antacid remedies or liquid heartburn medications (such as Gaviscon) at the same time as doxyPEP. It’s best to leave at least 2 hours between taking them to make sure the doxyPEP works properly. Heavy alcohol use can decrease the effectiveness of doxycycline.

If you need antibiotics for anything else, for example, a chest infection, then tell your doctor that you are taking doxyPEP.

Test regularly for STIs if having sex without a condom, and consider HIV PREP.

If you have sexual contact with someone with syphilis, you should still contact a sexual health clinic to discuss testing and the need for treatment.

For more information, please visit: DoxyPEP | Terrence Higgins Trust

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