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PrEP stands for Pre-Exposure Prophylaxis and is a way to help prevent HIV in people who are at substantial risk of contracting it by taking medication on a daily basis. The pill, which is used to prevent infection, is called truvada and contains a combination of two medicines, emtricitabine and tenofovir, often used to treat HIV in combination with other treatments.
For people who may have been exposed to the virus through intravenous drug use or unprotected sexual encounters, the medicines can help to prevent the virus from establishing a long term infection and eventually turning into AIDS - no longer a death sentence but nevertheless, a deeply unpleasant illness.
People with an increased risk of infection can reduce their chances of contracting HIV by as much as 92% when taking PrEP if it is taken correctly, but its effectiveness falls off sharply if the drug is not taken consistently.
Should you be using PrEP?
There are two main groups of people for whom PrEP is recommended; those whose sexual practices put them at risk and those who've had contact with intravenous drugs. It's only a course of treatment that's effective for those who have tested negative for HIV - for those who are HIV positive other courses of action are recommended, so it's important to be tested before you start on the treatment plan.
For people who are in a relationship with a partner who has a diagnosis, PrEP can reduce their risk of catching it, while those in a non-monogamous relationship with a man who identifies as gay or bisexual and who has taken part in anal sex without a condom or caught an STD in the past six months are also considered by the CDC to be at substantial risk.
In addition, people in a non-monogamous relationship with someone heterosexual who regularly does not use condoms with partners who are also at risk of infection, (ie, bisexual men or partners who inject drugs) and whose HIV status is unknown may be considered for the treatment.
Also considered to be at a substantial risk are people who have injected illicit drugs, been in treatment for drug use or shared needles and other injection equipment in the previous six months.
Will it stop me becoming infected with HIV?
It's only a treatment that's really useful for people with a consistent, ongoing risk of becoming infected with HIV. For one-off events which cause high risk of HIV exposure, other treatments are more effective.
Condoms are still important
HIV is unfortunately much more prevalent in the gay community than in the straight community for a number of reasons, and for that reason if you're engaging in anal sex with a non-monogamous partner whose HIV status you don't know, it's still important to use a condom.
While PrEP is a very effective way to decrease your chance of becoming infected it's not infallible and correctly using a condom remains the best way to avoid infection.