How PrEP works


Taking PrEP before being exposed to HIV means there’s enough drug inside you to block HIV if it gets into your body.

The medication used for PrEP is a tablet which contains tenofovir and emtricitabine (drugs commonly used to treat HIV). It is sometimes called Truvada but most of the PrEP we use in the UK is generic PrEP.

Where to get PrEP


PrEP is being made available to 10,000 people in England as part of the IMPACT trial, which started in September 2017. For further information and to find out how to join, see the PrEP Impact Trial website.

In Scotland, PrEP is being rolled out across the country by NHS Scotland from July 2017. Visit the PrEPScot website to find out more information about how to access it.

In Wales, a three-year pilot began in July 2017. This is open to all Welsh residents via GUM clinics, and there is no cap on the number of people who can access it. For more information see the Public Health Wales website.

All GUM clinics in Northern Ireland will be offering initial consultation and assessment appointments for a pilot trial, based at a centralised service in Belfast. This project will run for 2 years. There is currently no cap on numbers.

Additionally, if you have no income and live in England or Northern Ireland, you can apply for the Mags Portman PrEP Access Fund to get PrEP free of charge.

Quote text

Taking PrEP has enabled me to trust again, have relationships and build bridges.

Taking PrEP


In clinical trials PrEP has been used in two different ways:

  • taken regularly (one tablet per day).
  • only taken when needed (two tablets two to 24 hours before sex, one tablet 24 hours after sex and a further tablet 48 hours after sex).

This second method is often called ‘on-demand’ or ‘event based’ dosing.

Both methods have been shown to be very effective, although on-demand dosing has only been studied in gay and bisexual men.

Taking PrEP safely


If you’re thinking about getting PrEP from outside the NHS, it’s important that you talk to an adviser from a sexual health clinic. They will support you to use the treatment safely and provide necessary tests.

In all big PrEP studies, no one became infected if they took PrEP as recommended. But if you don't take it correctly, it may not work.

The drugs used in PrEP are the same drugs that are prescribed to thousands of people living with HIV every year. They’re very safe and serious side effects are very rare. 

A few people experience nausea, headaches or tiredness and, very rarely, the medication can affect kidney function. As a precaution, people taking PrEP have regular kidney function tests.

Although PrEP is highly effective at preventing HIV, it won’t protect you from other STIs or an unwanted pregnancy, which condoms would.

It’s important if you’re using PrEP that you go for regular STI screenings every three months.

More information

If you like to speak to someone about PrEP, call THT Direct on 0808 802 1221.