PEP

Is it too late once HIV is inside someone?

No! After unsafe sex or if a condom breaks it's possible to stop someone becoming HIV positive if you act fast.

When HIV gets into someone's bloodstream it takes time before the virus permanently infects them. Starting something called PEP (post exposure prophylaxis) during this short period can kill the virus before this happens.

PEP is a month long course of HIV drugs available from sexual health clinics and some hospitals. If you need PEP the best advice is to go to your local sexual health clinic or the Accident and Emergency Department of your local hospital as soon as you can. If you need PEP when your sexual health clinic is open the best idea is to go there and ask for PEP because you have been exposed to HIV. Out of office hours and at weekends go to Accident and Emergency and say the same thing.

PEP's not guaranteed to work and can have side effects (eg, diarrhoea and feeling sick) so isn't to be used instead of condoms. But it makes getting infected much less likely.

PEP has the best chance of working if it's started within 24 hours of the risk happening but it might be given up to 72 hours (three days) later.

One day you - or someone you have sex with - might need PEP. For more information on it, when it's given and where to get it check out:

• the PEP booklet available in gay venues or from the website below
• the web site www.chapsonline.org.uk/pep
• or call THT Direct on 0808 802 1221.

• This article was last reviewed on: 18/10/11
• Date due for next review: 18/10/13