PrEP is an antiviral tablet that helps to prevent HIV. You can take it if you’re at increased risk of becoming infected with the virus.
Get expert advice on PrEP, and find out if it’s right for you. Take our consultation and order PrEP online.
PrEP (short for pre-exposure prophylaxis) is a type of antiviral treatment that helps to protect you from getting HIV. It’s specifically for people who have an increased risk of getting HIV. So for example, if your sexual partner is HIV positive, you may benefit from taking PrEP daily in addition to using a condom.
With PrEP, you can also do what’s called ‘event-based dosing’. For example, if you’re going on holiday and likely to be having sex with casual partners, there’s a way you can take it called ‘holiday PrEP’ or ‘on-demand PrEP’, where you take it for a short period of time to increase your protection.
PrEP is available as a branded tablet (Truvada) and as a generic pill (Emtricitabine/Tenofovir disoproxil, or Generic PrEP). The way they work should be the same, but the way the tablet looks and the company that makes them are different. Generic PrEP also tends to be much cheaper.
PrEP contains two active ingredients: emtricitabine and tenofovir. In short, these drugs stop the virus from making an enzyme it needs to replicate itself. When HIV is transmitted from one person to another, there’s an ‘incubation period’ where these viral cells convert their own genetic material from RNA into DNA. This is the process that the medicines in PrEP interfere with, to stop the virus from developing.
PrEP is recommended if you’re HIV negative but experience situations where you’re at high risk of contracting HIV.
PrEP may help you if:
But if you’re HIV positive, you shouldn’t take PrEP, because the dose isn’t high enough to suppress the virus. The treatment for this is very similar to PrEP, but the dose and the way you take it is different.
Clinical studies have found that taking PrEP can reduce the risk of HIV infection by 86% . Taken daily, it’s been estimated to be 88-90% effective, if not higher .
If you take it every day, it takes seven days for PrEP to become fully effective at preventing HIV transmission through anal sex. If you’re a woman taking it for vaginal sex, it takes 21 days.
How we source info.
When we present you with stats, data, opinion or a consensus, we’ll tell you where this came from. And we’ll only present data as clinically reliable if it’s come from a reputable source, such as a state or government-funded health body, a peer-reviewed medical journal, or a recognised analytics or data body. Read more in our editorial policy.
There are four different ways to take PrEP. The way you take it will largely depend on how and when you plan to have unprotected sex.
Daily use is the most effective, but isn’t the only way of taking it. If you’re not having sex regularly, taking it in another way that means you take less tablets can still be effective, and ultimately save you money. If you’re not sure what the best way to take it is, let us know, and we’ll give you the advice you need.
If you’re taking PrEP over a long period, you’ll also need to get tested regularly to make sure you don’t have HIV. This is a blood test usually done every three months.
Like the name suggests, daily use of PrEP is where you take one pill every day at the same time. It’s suitable for you if you’re having anal or vaginal sex. Your protection starts after seven days of taking it like this. It’s a good way to protect yourself if you’re having sex regularly with an infected person.
T’s and S’s is where you take PrEP on specific days of the week: Tuesday, Thursday, Saturday and Sunday. It’s only suitable for anal sex and is a good form of protection if you have sex once or twice a month.
If you’re doing daily use or T’s and S’s, you should take your pill at the same time every day.
Also called ‘event-based dosing’, on-demand is where you take:
It’s helpful if you know you’re having unprotected sex 24 hours in advance, but is only suitable for you if you’re having anal sex.
The 7-7-7 method, sometimes called ‘holiday PrEP’, is for when you plan to have sex multiple times, with multiple partners, within a short space of time. You’ll take one tablet a day for:
seven days before you ‘go on holiday’ (or your period of having sex starts)
every day during your holiday (your period of having sex)
and for seven days after your holiday (after your period of having sex finishes)
So the 7-7-7 name is based on your holiday lasting seven days, but it may be longer or shorter than this. It’s suitable for both vaginal and anal sex.
You shouldn’t take PrEP if you’re HIV positive, because it won’t help to suppress the virus in your body. To do this, the dose needs to be stronger. In fact, if you take PrEP but are HIV positive, it could make the drug less effective overall, because the dose is at a size where the virus can learn how to become resistant to it.
So if you’re HIV positive, you should speak to your GP or sexual health clinic about getting the treatment that’s right for you.
How we source info.
When we present you with stats, data, opinion or a consensus, we’ll tell you where this came from. And we’ll only present data as clinically reliable if it’s come from a reputable source, such as a state or government-funded health body, a peer-reviewed medical journal, or a recognised analytics or data body. Read more in our editorial policy.
How we source info.
When we present you with stats, data, opinion or a consensus, we’ll tell you where this came from. And we’ll only present data as clinically reliable if it’s come from a reputable source, such as a state or government-funded health body, a peer-reviewed medical journal, or a recognised analytics or data body. Read more in our editorial policy.
Pre-exposure prophylaxis to prevent the acquisition of HIV-1 infection (PROUD): effectiveness results from the pilot phase of a pragmatic open-label randomised trial. The Lancet, 387(10013), pp.53–60.
Effective HIV Prevention Strategies.
Non-branded version of Truvada. Tablet you can take in different ways to lower your risk of HIV.
Original PrEP tablet. Reduces likelihood of contracting HIV for people who are at risk.
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