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PrEP – Treatment to protect you from HIV

Go to your online account to make your PrEP appointment


PrEP (Pre-Exposure Prophylaxis) is a medicine for HIV negative people, taken before sex, so it is “pre-exposure”. Prophylaxis means to prevent infection- in this case, HIV. It can reduce the risk of getting HIV when taken as instructed.

PrEP is made up of two drugs, Tenofovir and Emtricitabine, taken as a single pill. These drugs are known as antiretroviral medicines and have been used as a part of HIV treatment for many years. You may know this medicine by its brand name, “Truvada”.

Results in trials have been very successful, with PrEP significantly lowering the risk of becoming HIV positive and without major side effects. In trials, if people took the pills as prescribed, the protection PrEP provided from HIV is close to 100%.

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

  • Taken daily (one tablet per day)
  • Taken when needed (2 tablets two to 24 hours before sex, 1 tablet 24 hours after sex and a further tablet 48 hours after sex). This is often called ‘on-demand’ or ‘event-based’ dosing.

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

PrEP does not protect people from other STIs, and people on PrEP should get regular full STI tests to look after their general sexual health.

  • Is PrEP right for me?

    PrEP has been shown to be most useful for people who are at high risk of getting HIV. This includes people who might have difficulties with regular condom usage from communities which are disproportionately affected by HIV, such as:

    • Gay and bisexual men
    • Black Africans
    • Trans people
    • Those in a relationship with an HIV positive partner who are not on successful treatment.

    It is important for people on PrEP to be able to:

    • Take the medication as prescribed
    • Have an HIV test and kidney function tests at a sexual health clinic before starting PrEP
    • Test for STIs regularly
  • How can I get PrEP?

    PrEP is now funded as a free NHS treatment 

    If you are interested in getting PrEP in this way then please book a ‘New PrEP’ appointment on your online account.

    If you already get PrEP from Unity then please book a a ‘PrEP Follow-up’ appointment on your online account.

    Buying generic PrEP online

    Some people are also buying generic versions of Tenofovir/Emtricitabine from online pharmacies. If you live in the UK it is legal to buy and import PrEP as long as it is for personal use only, and you buy no more then 3 months’ supply at once .

    Some UK sexual health clinics have undertaken drug level testing on people who have been ordering generic PrEP online to check the validity of the drugs. Reports indicate that good levels of active drug have been reported, with it being recommended that people stick to ordering types of generic PrEP which are listed on the US Food and Drug Administration (FDA). Iwantprepnow lists current sources of online generic PrEP which has been previously validated by drug level testing from these sexual health clinics.

    If you’re thinking about getting PrEP from outside the NHS England Impact trial, it’s important that you talk to a sexual health adviser,  doctor or nurse, such as those at Unity. We will be able to support you to use the treatment safely and provide necessary tests  before starting PrEP (such as a HIV test and kidney function test), and help with STI screens and monitoring.

  • PrEP monitoring at Unity

    If you are planning to start taking PrEP, or are already taking PrEP and require monitoring, please attend a Unity clinic.

    Before starting PrEP, it is advised that you:

    • Have a HIV test to make sure you are HIV negative
    • Have kidney function tests
    • Have a full sexual health screen
    • Chat to one of our health advisers to talk about taking PrEP safely


    If you are already taking PrEP, we can:

    • Monitor your kidney function
    • Offer a full sexual health screen every 3 months
    • Offer an HIV test every 3 months
    • Offer a discussion with our health advisers about safer sex
  • More information on PrEP

    If you would like more information on PrEP:

  • Running low on PrEP?

    If you’re running low on PrEP, please see here for proactive steps you can take to maintain protection.

  • What to do if you miss a dose of PrEP and have unprotected sex?

    Daily dosing

    If you have had an least 4 doses in the last 7 days, take your next dose when its due and continue daily dosing. You will have adequate protection, and do not need to abstain from sex.

    If you had fewer than 4 doses in the last 7 days you might require PEPSE. Call Unity within 48 hours of the unprotected sex 0117 342 6944 for advice (or if we’re closed attend A&E to request PEPSE).

    Event-based dosing

    If you have not taken your PrEP prior to sex, you might require PEPSE. Call Unity within 48 hours of the unprotected sex 0117 342 6944 for advice (or if we’re closed attend A&E to request PEPSE).


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