Men at risk for HIV infection can safely take pre-exposure prophylaxis (PrEP) when they need it, instead of every day. In a study of gay and bisexual men, researchers found that taking 4 doses of PrEP around the time of sexual activity cut the risk of being diagnosed with HIV by 97%.

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Men at risk for HIV infection can safely take pre-exposure prophylaxis (PrEP) when they need it, instead of every day. In a study of gay and bisexual men, researchers found that taking 4 doses of PrEP around the time of sexual activity cut the risk of being diagnosed with HIV by 97%.