How effective is PrEP?

When taken as prescribed, PrEP – the HIV prevention pill – is highly effective! If you’re exposed to HIV while taking PrEP, the medicine can block HIV from taking hold in the body. In a major study of gay and bi men, as well as trans women, daily PrEP use lowered their risk of getting HIV by an estimated 99 percent – that’s pretty amazing!

If you decide to start PrEP, remember that it will take some time for the pill to reach maximum effectiveness – at least seven days for men who have sex with men, and longer if you are a woman having vaginal sex.

Find out if PrEP is right for you. Click here to find a PrEP-friendly provider near you. 


#AskTheHIVDoc is a video series from Greater Than AIDS featuring top HIV doctors providing answers to commonly-asked questions about HIV prevention, testing and treatment.

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