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PEP and PreP

What is Post Exposure Prophylaxis (PEP)?

‘Post-exposure prophylaxis after sexual exposure’ (PEPSE) is medication to prevent contracting HIV after a recent risk of exposure to the virus. In this situation the risk is unprotected sex with someone who is HIV positive or thought possibly to be living with HIV. Unprotected sex means sex without a condom, or sex with a condom which breaks or comes off during sex.

By far the best policy is to avoid contracting HIV. Although PEPSE can be very useful in emergency situations, using condoms during sex is the most effective way of preventing HIV.

Do I need to take PEPSE?

If you are HIV negative or have never had an HIV test, you should seek advice if, in the last 72 hours-

  • You think you may have come into contact with HIV during unprotected sex, or-
  • You were sexually assaulted by a stranger

The risk of catching HIV from a single sex act is very small. However, research shows that that acquiring HIV is less likely if you take PEPSE. PEPSE does not work every time and some people may have contracted HIV despite taking PEPSE. PEPSE is less likely to work if you miss tablets or if you don’t complete the full 28 day course.

If you think you need PEPSE ask for help immediately. Do not delay, as every hour counts. The sooner PEP is started, the more likely it is to work; within 24 hours is best, but no later than 72 hours (three days). It is important for you to know that PEPSE is not always needed after unprotected sex. The drugs are the same ones taken by people living with HIV, and for PEP to work they must be taken for four weeks

It is free of charge but can only be prescribed by doctors and if certain criteria are met. Sexual health and HIV clinics can provide it, as can Accident & Emergency departments of hospitals. Regular family doctors (GPs) don’t give PEP.

Where can I get PEP?

PEP is available from bSHaW Specialist Sexual Health Clinics. However, please be aware that all Clinics are closed on Bank Holidays, therefore in case of an emergency:

If somebody needs PEP when the clinics are closed people should go to A&E at Stoke Mandeville Hospital for sexual exposure and for occupational exposure the Urgent Treatment Centre (UTC) or A&E.

Find your nearest bSHaW Specialist Sexual Health Clinic here 

What is PrEP?

PrEP is short for Pre-Exposure Prophylaxis. It’s a form of medicine which prevents HIV. It is taken by a HIV negative person before sex and exposure to HIV. It is available for free to some people through the NHS and also at SHAW High Wycombe and Brookside Aylesbury sexual health clinics. You will require a medical consultation to assess your suitability for the provision of PrEP.

How do I access free PrEP

If you think you would benefit from PrEP and fit into one of the categories below please call 0300 303 2880 for an assessment.

    • You have a sexual partner with HIV who is not on treatment or who has a detectable viral load.
    • You are a gay or bisexual man who has anal sex without condoms, whether you are top, bottom or versatile.
    • You are a trans man or trans woman who has anal or vaginal/front hole sex with men.
    • You have recently had syphilis, or a sexually transmitted infection in your bottom.
    • You’ve been given PEP more than once in the last year

Taking PrEP and how effective is it?

  • How it Works

It involves a HIV negative person taking tablets containing the drugs Tenofovir and Emtricitabine. The tablets need to be taken before sex for it to work. Taking PrEP before any HIV exposure means there’s enough drug inside you to block HIV if it gets into your body. PrEP can be taken regularly or when needed. It is important to take it correctly for it to work effectively

  • Effectiveness

Studies show that if PrEP is taken correctly, the chances of getting HIV while you’re on it are almost zero. It’s a really powerful tool for helping prevent new HIV infections.

  • PrEP only protects against HIV not other STIs

It can’t protect you against other sexually transmitted infections like gonorrhoea and syphilis. You can use condoms to protect against these other STIs (Sexually Transmitted Infections).

Reasons you may not need PrEP:

    • If you are in a relationship with someone and neither of you is having sex with anyone else, once you have both tested negative for HIV then you don’t need PrEP.
    • If your only partner is HIV positive, taking treatment with an undetectable viral load then they are no longer infectious to others. You do not need PrEP because their treatment protects you from HIV. PrEP would not add any extra benefit.
    • If you are a gay or bi man or trans person and you are not having anal sex at the moment, then you’re not at risk of catching HIV. Unprotected anal and vaginal sex leads to far more HIV infections than oral sex.
    • If you are already using condoms all of the time for anal (or vaginal/front hole) sex, then PrEP is not needed because condoms offer excellent protection against HIV as well as other STIs. As a back-up plan, in case of a condom accident then you can always attend for PEP (emergency medicine to prevent HIV) as soon as possible within 72 hours of unprotected sex.

I want to access PrEP outside of the NHS

If you are considering accessing PrEP from outside the NHS, it is still important to talk to an adviser from the sexual health clinic. Call 0300 303 2880.

Find out more about PrEP: