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What is pre-exposure prophylaxis (PrEP)?


Truvada - the drug used as PrEP


  • Pre-exposure prophylaxis (PrEP) is a course of HIV drugs taken daily by HIV-negative people at greater risk of HIV to prevent infection.
  • PrEP can virtually eliminate the risk of getting HIV if taken consistently and correctly.
  • PrEP won’t protect you against other sexually transmitted infections (STIs) such as hepatitis C, but condoms will.  

What is PrEP?

Pre-exposure prophylaxis (PrEP) is a course of HIV drugs taken daily by HIV negative people most at risk of HIV to reduce their risk of HIV infection.

Truvada is currently the only drug approved for use as PrEP. Truvada is a single pill that is a combination of two anti-HIV drugs, tenofovir and emtricitabine.

How does PrEP prevent HIV?

If you have exposed yourself to HIV, for example by having unprotected sex with someone who is living with HIV, taking PrEP correctly can stop the virus from establishing itself in your body.

How effective is PrEP?

If used consistently, PrEP can reduce the risk of getting HIV from unprotected sex by over 90%. If you inject drugs, PrEP can reduce your risk of HIV by more than 70%.

However, because it’s not 100% effective, it should always be used with condoms, safer sex practices, clean injection equipment, and other HIV prevention methods.

If I take PrEP, can I stop using condoms?

No, you shouldn’t stop using condoms. While it significantly reduces your risk of HIV infection, PrEP isn’t fully protective and should be combined with other methods like condoms to reduce your risk even further.

PrEP also doesn’t give you any protection against sexually transmitted infections (STIs). That’s why it’s doubly important to use condoms as they are highly effective at preventing HIV and some STIs like gonorrhoea and chlamydia.

Who can take PrEP?

PrEP isn’t recommended for everyone. It’s for people who are HIV-negative and at a high risk of HIV infection.

PrEP may be an option for you if:

  • you’re in an ongoing relationship with a partner living with HIV
  • you’re sexually active with more than one person, even if they recently tested negative for HIV
  • you’re a heterosexual who doesn't use condoms with partners whose HIV status is unknown and are at high risk of HIV infection (for example, they inject drugs or have bisexual male partners)
  • you’ve shared injecting equipment or have been in a treatment programme for injecting drug use
  • you’re in a heterosexual relationship where one partner has HIV and the other doesn’t, to protect the uninfected partner during conception and pregnancy.

Where is PrEP available?

Currently, PrEP is available in the USA, South Africa, Kenya, Canada, France, Israel and Peru. The European Commission approved PrEP in September 2016 and many other countries are close to offering the service.

International guidelines now recommend that PrEP should be made widely available, so even if it's not available to you right now, it may be an option in the future.

How can I start PrEP and how long do I take it for?

If PrEP is available in your country, talk to your healthcare professional to find out if it’s the right HIV prevention option for you.

PrEP needs to be taken every day for it to work. Also, you must take an HIV test before starting PrEP to be sure that you don’t already have HIV.

Every three months while you’re taking it, you’ll have to visit your healthcare professional for regular check-ups.

Does PrEP have any side effects?

In some people PrEP can cause minor side effects like nausea, vomiting, fatigue and dizziness, but these eventually disappear over time.

If you’re taking PrEP and experience any side effects that are severe or don’t go away, tell your healthcare professional.

Last full review: 
08 February 2016
Next full review: 
08 February 2019

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Last updated:
24 May 2017
Last full review:
08 February 2016
Next full review:
08 February 2019