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PEPSE (Post Exposure Prophylaxis after Sexual Exposure)


PEPSE (Post Exposure Prophylaxis after Sexual Exposure) is a type of medication that can be taken up to 72 hours after exposure to HIV to stop you becoming infected.

If you’ve had sex without a condom, or if the condom broke during sex, you may be able to use PEPSE.

It is vital that this medication is given within 72 hours of the potential exposure to the virus as the medication is not effective after this time. The earlier PEPSE can be given the better. If you’ve had sex with somebody who you think may be HIV positive within the last 72 hours, it’s important to get help straight away. Please don’t leave it until the 72 hours is up or nearly up.

  • The medication needs to be taken for one month after the initial dose to be effective
  • It can have unpleasant side effects, e.g. nausea, diarrhoea
  • PEPSE medication is not 100% guaranteed to work
  • You will need to be monitored carefully during the month when you take the tablets and then for another three months afterwards
  • If you have had a condomless sex or a condom breakage during sex with someone who is HIV positive, please attend Whittall Street Clinic (if it’s within opening hours) or your local A&E department straight away
  • The doctor you see will take some blood tests from you, to check for liver function, kidney function, blood count and may test for hepatitis B and syphilis
  • You will have a HIV test prior to starting treatment, as if you are already HIV positive, giving PEPSE may reduce the types of HIV medication which could be used to treat you in the future
  • The doctor will explain how to take the medication and ask you to sign to say you are happy to take it
  • You will be asked to attend a further appointment to ensure you are not having any problems with the medication
  • Once you have finished the month’s course you will have an appointment for blood tests to check your kidney and liver function
  • After three months you will be asked to come back in for a final HIV test


PEPSE should never be thought of as a substitute for using condoms.

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