How effective is PrEP?
PrEP is highly effective for preventing HIV.
PrEP reduces the risk of getting HIV from sex by about 99% when taken as prescribed.
Although there is less information about how effective PrEP pills are among people who inject drugs, we know that PrEP pills reduce the risk of getting HIV by at least 74% when taken as prescribed. Currently, PrEP shots are not recommended for people who inject drugs.
PrEP is less effective when not taken as prescribed.
If I am not at ongoing risk for getting HIV, can I take PrEP only when I’m at risk?
Although the updated PrEP guideline provides information on how to correctly use the “2-1-1” schedule, this approach is not approved by the U.S. Food and Drug Administration (FDA) and is not recommended by CDC. Taking PrEP as prescribed is currently the only FDA-approved schedule for taking PrEP to prevent HIV. When taken as prescribed, PrEP is highly effective for preventing HIV.