The Information Standard
CHAPS PEP booklet

PEP is a course of anti-HIV medication that needs to be taken daily over the course of a month. The drugs have been available for HIV prevention since the early-to mid-1990s for health workers who have had 'needle-stick' or similar injuries. More recently, PEP has been made available under strict prescribing guidelines to people who might have been exposed to HIV during sex.

The sooner PEP is started, the more effective it is. So you must act quickly if you want to take PEP, within 24 hours of the risk is best and no later than 72 hours (three days).

PEP can cause severe side effects like diarrhoea, nausea and prolonged headaches.

PEP should be available from sexual health clinics and hospital accident and emergency departments. Many men say they have had difficulty obtaining PEP from these places, especially outside metropolitan areas. You are more likely to be successful if you enquire at a sexual health clinic or Accident and Emergency (A&E) department in a hospital where there is also a specialist HIV clinic.

You must also meet the prescribing guidelines for PEP, to find out if you are likely to meet the criteria, use our online self-assessment tool.

PEP has a good chance of stopping someone getting HIV but it's not guaranteed to work and it's not a cure for HIV. Condoms and lube are still the best way of stopping the spread of HIV.

To start learning more about PEP, click here

  • This article was last reviewed on: 11/10/2011
  • Date due for next review: 11/10/2013

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