Post-exposure prophylaxis (PEP) is a medicine that can stop HIV. You need to start taking it within 72 hours (3 days) of being in contact with the virus for it to work properly.

PEP is a course of medication that needs to be taken regularly for a month. There are national guidelines about who can be given PEP. If you meet those guidelines you can get the treatment for free from the NHS.

When taking PEP, you are still at risk of transmitting or contracting HIV, so we recommend using condoms when you have sex. It‘s important you take the medication as instructed and do not miss any tablets. After you’ve completed the course of medication, you’ll need to have some follow up blood tests.

If you think you need PEP, go to a sexual health or HIV clinic. If they’re closed, you can go to A&E.

The best way to prevent HIV infection during sex is to use condoms consistently and correctly.


For more information go to: Terrence Higgins Trust - you can also call THT Direct on 0808 802 1221.


Helen Burkitt, Senior Sexual Health Nurse at SH:24
Written by Helen Burkitt. Senior Sexual Health and Contraception Nurse

Last updated at: 29 March 2022

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