Pre-exposure prophylaxis (PrEP) is a medication taken to prevent HIV. PrEP, taken once daily, is highly effective for preventing HIV.
PrEP reduces the risk of getting HIV by about 99% when taken as prescribed.
Although there is less information about how effective PrEP is among people who inject drugs, we do know that PrEP reduces the risk of getting HIV by at least 74% when taken as prescribed.
PrEP is much less effective when it is not taken as prescribed.