What is PEP?
PEP stands for Post-Exposure Prophylaxis.
PEP is a form of emergency prevention treatment for people who don't have HIV and who have been exposed to the virus (e.g. through unprotected sex).
It is a combination of HIV medication that works by stopping the HIV virus from replicating in your body.
PEP involves taking either a single dose (one tablet) once a day for 28 days, or 2 tablets once a day for 28 days. You need to start the course within 72 hours (3 days) of exposure, ideally within 24 hours. The sooner you start taking it, the more effective it will be.
PEP is only to be used in emergency situations and as a last resort. Its effectiveness is not guaranteed, so prevention methods are highly recommended. It does not offer protection against other STIs, or unplanned pregnancy. Find out how to protect yourself from STIs here.
If you are taking PEP, it is very important that you do not miss any tablets and complete the entire course as instructed. PEP is less likely to work if you do not take the entire course correctly.
Anyone who has been exposed to the HIV virus can take PEP. Exposure can be from:
- Unprotected sex
- Needlestick injuries
- Occupational exposure
- Sharing needles
- Missing PrEP doses
- Sexual assault
You may need to stop taking certain medications, vitamins and supplements during treatment. Your doctor or nurse will advise you on how long these need to be stopped for.
You can get PEP free from sexual health clinics and specialist HIV clinics.
If these are closed or not local to you, you can visit your nearest Accident & Emergency (A&E) department. You should be seen as soon as possible due to the limited timeframe you have to start treatment.
You will need to take an HIV test as soon as you have finished your PEP treatment. A further HIV test will then be taken 4-6 weeks later (11 weeks after exposure). Your liver and kidneys will be monitored before and after treatment.
If your HIV test comes back negative - meaning you have not caught the virus - you may be advised to start taking PrEP if you have an ongoing risk of HIV transmission, or to use regular contraception.
If your HIV test comes back positive - meaning you have caught the virus - you will be started on anti-viral medication and referred to HIV specialist services where you will be supported.