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PrEP (Pre-Exposure Prophylaxis)

This fact sheet answers frequently asked questions about PrEP (Pre-Exposure Prophylaxis).

HIV Pre-exposure prophylaxis, or PrEP, is a medicine used to help protect against getting HIV. Currently this medicine is available as a daily pill, but new forms of PrEP are being developed. If you do not have HIV but think you are at high risk, talk to your healthcare provider about PrEP.

The basics

Who should take PrEP?

PrEP is for anyone who has an ongoing risk of getting HIV. This includes anyone who is not infected with HIV but is in an ongoing relationship with an HIV-positive partner. It also includes anyone who has multiple sexual partners without consistent use of condoms or who has unprotected sex. Gay or bisexual men who have anal sex without a condom should consider PrEP.

Sexually active people who inject drugs or use other substances that may impair their judgment should also consider PrEP. Do not share PrEP medication with anyone. It is never a good idea to share prescription drugs.

Can anyone use PrEP?

PrEP is for people who are HIV negative and are at ongoing high risk for HIV infection. People who need to prevent HIV after a single high-risk HIV exposure need post exposure prophylaxis, or PEP. Talk to a healthcare provider to find out which option is best for you. If you do not have a healthcare provider, contact the Mayor's Health Line at 617-534-5050 for help in finding care in Boston.

How often do I need to take PrEP?

With the medicine currently available, people who use PrEP must take medicine daily and see their health care provider for regular follow-ups. When taken consistently, PrEP reduces the risk of HIV infection in people who are at high risk by as much as 92%. PrEP is less effective if it is not taken consistently.

If PrEP protects against HIV, do I need to still use other prevention methods?

Yes. PrEP is a powerful HIV prevention tool, but it does not protect you against other sexually transmitted infections. Use condoms to protect against these other infections.  

Is taking PrEP safe?

Yes, but it is important to follow-up regularly with your healthcare provider while taking PrEP. As with any medicine, some side effects can occur.

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