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​What is PEP?

PEP (Post-exposure prophylaxis) is taking medicines that work against Human Immunodeficiency Virus (HIV) after being exposed to HIV in a way that might cause infection.  If you have a significant exposure to HIV, the sooner you can start PEP, the better! So you should contact a healthcare provider as soon as possible after being exposed to find out if PEP is right for you.

Who should take PEP?

PEP should be used by anyone who may have been exposed to HIV very recently during a single event. Health care workers recently exposed to blood or body fluids of a patient who is infected with HIV and people who may have been exposed to HIV during a single event unrelated to work (such as unprotected sex, needle-sharing injection drug use, or sexual assault) should consider taking PEP. It is not the right choice for people who may be exposed to HIV frequently. People who may be exposed several times to HIV should talk to their healthcare provider about PrEP (pre-exposure prophylaxis).

Can anyone use PEP?

PEP should only be used in situations right after a potential HIV exposure. PEP does not replace regular use of other proven HIV prevention methods, such as PrEP, correct and consistent condom use, or use of sterile injection equipment. If you are given PEP, you will be asked to return for HIV testing at 4 to 6 weeks, 3 months, and 6 months after the potential exposure to HIV. Because PEP is not always effective, continue to use condoms with sex partners while taking PEP. Never share injection equipment with others.

Does PEP have any side effects?

PEP is safe but it may cause nausea and other side effects such as diarrhea and headaches in some people.

Where can I get PEP?

Your primary care provider, emergency rooms, or urgent care clinics may be able to provide PEP. Remember, if you have been significantly exposed to HIV, get medical follow-up right away. 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.


Boston Public Health Commission
1010 Massachusetts Ave, 6th Floor, Boston, MA 02118.
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