PrEP/Stop Aids

PrEP and PEP


“PrEP” stands for Pre-Exposure Prophylaxis. PrEP is a way for people who don’t have HIV to prevent HIV infection by taking a pill every day. If you take PrEP and are exposed to HIV, these medicines can work to keep the virus from taking hold in your body.


PrEP is considered for people who are HIV-negative and at risk for HIV infection.

People who use PrEP must be able to take the drug every day and to return to their health care provider every 3 months for a repeat HIV test, prescription refills, and follow-up.

Also, PrEP is for people who are at ongoing risk of HIV infection. For people who need to prevent HIV after a single high-risk event of potential HIV exposure—such as sex without a condom, needle-sharing injection drug use, or sexual assault—there is another option called post-exposure prophylaxis, or PEP. PEP must begin within 72 hours of exposure. (See below more information).


Some people in clinical studies of PrEP had early side effects such as an upset stomach or loss of appetite, but these were mild and usually went away within the first month. Some people also had a mild headache. No serious side effects were observed. You should tell your healthcare provider if these or other symptoms become severe or do not go away.


Most insurances cover PrEP. Those who do not have insurance coverage may qualify for assistance. There are also assistance programs for those who have high insurance copays.


Yes. Post-exposure prophylaxis (PEP) involves taking anti-HIV medications as soon as possible (within 3 days) after you may have been exposed to HIV to try to reduce the chance of becoming HIV positive. PEP is a month-long course of emergency medication taken to try to keep HIV from making copies of itself and spreading through your body.

PEP must begin within 72 hours of exposure, before the virus has time to make too many copies of itself in your body. PEP consists of 2-3 antiretroviral medications and must be taken for 28 days. Your doctor will determine what treatment is right for you based on how you were exposed to HIV. You will be asked to return for follow-up appointments and additional HIV testing.

PEP is safe but may cause side effects like nausea in some people. These side effects can be treated and are not life threatening. PEP is not 100% effective; it does not guarantee that someone exposed to HIV will not become infected with HIV.

You should be evaluated for PEP at an in-person appointment with a health care provider. If you believe you have been exposed to HIV, you can call the office during business hours for assistance getting a timely appointment. If you need PEP during a time when the office is closed, you should go to the nearest urgent care clinic or emergency room.


PEP is used by anyone who may have been exposed to HIV during a single high-risk event such as an episode of unprotected sex, needle-sharing injection drug use, or sexual assault.

Keep in mind that PEP should only be used in uncommon situations right after a potential HIV exposure. PEP is not intended for long-term use. It is not a substitute for regular use of other proven HIV prevention methods, such as pre-exposure prophylaxis (PrEP), correct and consistent condom use or use of sterile injection equipment.

Because PEP is not 100% effective, you should continue to use condoms with sex partners while taking PEP and should not share injection equipment with others. This will help avoid spreading the virus to others if you become infected. If you have repeated exposures to HIV, you should consider PrEP. See our PrEP page.


Most insurances cover PEP. Those who do not have insurance coverage may qualify for assistance.