(Post-Exposure Prophylaxis)

PEP is a prescribed medicine for people who are HIV negative and think they may have been exposed to HIV.

PEP is taken for 4 weeks. It decreases the chance of the virus from infecting your body. PEP does not work 100% of the time.

Do not delay. You need to take PEP within 72 hours of exposure.

 What should I do if I may have been exposed to HIV?

PEP needs to be taken as soon as possible after you have been exposed, ideally within 72 hours.

How Much Does PEP Cost?

Those who have been sexually assaulted or exposed to HIV at work, may be eligible for free PEP.

When PEP is taken for any other reason, it may cost between $600 and $1200 if not covered by a drug-benefit plan.

Should I Take PEP?

  • If you are HIV negative and had a high-risk exposure to HIV (and/or if you answer "Yes" to any of the following questions), go to the nearest Emergency Department or speak to your health care provider right away about your risk of exposure.
  • Did you have unprotected sex (vaginal or anal) with someone who you know is HIV positive?  (Unprotected means that a condom was not used, or that the condom broke or slipped off during sex.)
  • Did you share needles (for drugs, hormones, or tattoos) or other drug injection equipment with someone who you know is HIV positive?
  • Have you been exposed to HIV at work? E.g. being stuck by a needle or exposed to blood and body fluids that may be infected.

 What can I expect when I ask about PEP?

  •  You will be asked questions about your exposure to HIV. Your answers will help you and your health care provider determine whether PEP will help you. Some exposures are very low risk and may not need PEP.
  • You will get an HIV test. You have to agree to testing (give consent) before you can be tested. The HIV test is important. The treatment plan will be different if you already have HIV. If you do not agree to HIV testing, you may not be able to get PEP.
  • If the person you were exposed to is with you or can be reached, the health care provider will offer them an HIV test also. If that person is tested and does not have HIV, it may mean that you do not need PEP or can stop taking PEP.
  • You may also be tested for other infections called sexually transmitted infections (STIs) and blood borne infections (BBIs) such as syphilis, hepatitis B and C.
  • You may be given vaccines against other diseases, such as hepatitis B.
  • If you are a woman, you may be asked to do a pregnancy test. If you are not currently pregnant, your health care provider may discuss whether or not you need or want to take emergency contraception. 
  • Your health care provider will talk with you about how to lower your risk and avoid HIV exposure in the future. If used correctly, male condoms are the best way to prevent an HIV infection.

 How do I get the medication?

  • If needed, PEP will be prescribed by your health care provider or at a hospital Emergency Department. Some Emergency Departments will provide your first dose of PEP or a few doses of PEP. This will give you time to fill your prescription for the rest (or have a follow-up appointment for a more comprehensive assessment).
  • PEP is not a "morning after pill." You must take it for 28 days. Do not skip doses. Pills should be taken at the same time every day.
  • Before you start taking PEP, tell your health care provider about all the other medicines you take. Also let them know about over-the-counter drugs, herbals, or vitamins you may be taking.
  • Do not stop taking PEP. You must complete the full course of PEP to have the best chance of stopping HIV infection. Stop only if your health care provider tells you.

 Does PEP have side effects?

Yes, common side effects include: upset stomach, tiredness, diarrhea, and headaches.

Tell your health care provider right away if the side effects are so bad that you cannot handle them. Do not stop taking PEP before talking to your health care provider. There may be ways to help you deal better with the side effects.

 Will I have to go to follow-up appointments after I start taking PEP?

Yes. You will be referred for follow-up after you begin taking PEP. At this visit, your health care provider will ask if you have any questions, and will talk with you about any problems you are having taking PEP. They may be in touch with you weekly, either in person or by phone, to check in and see how you are doing. Let your health care provider know immediately if you have a fever, body aches, or rash.

Your health care provider will also talk about how you can protect yourself and others while you are taking PEP and after. During the 12-week period after your exposure, try to protect others from possible exposure to HIV by doing the following:

  • Use condoms every time you have sex
  • Use birth control to avoid becoming pregnant
  • Do not breastfeed
  • Do not share needles
  • Do not donate blood or semen

Can I take PEP if I am pregnant?

 Yes, if you are pregnant, you can still take PEP. Your health care provider will discuss the benefits and risks for you and your baby.

You should stop breastfeeding for 3 months after a potential HIV exposure. Ask your health care provider about pumping and discarding breast milk if you are HIV negative and want to go back to breastfeeding after the 3-month period.

What happens after I finish taking PEP?

You should get an HIV test when you are finished taking PEP and then again 2 months later - if both tests are negative, you did not become infected with HIV from the exposure.

Discuss with your health care provider how you can protect yourself in the future. You can be linked to services that can help you lower your risk of HIV infection. Today there are many tools to help you stay HIV-free, such as the use of condoms and clean needles which are very important.

If you have had access to or tried to access PEP in Durham we would like for you to complete a short 2 question survey about your experience.  CLICK HERE for the survey!

What is PrEP?

(Pre-Exposure Prophylaxis)

How's it different from PEP?





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Phone: (905) 576-1445 Toll Free: (877) 361-8750

Email: Education@aidsdurham.com



HIV and STI Testing - Sexual Health Information

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LGBTQ (lesbian, gay, bisexual, transgendered and questioning) helpline.

If you are in crisis and calling outside of Prideline Durham's hours of operation, please contact the Distress Centre Durham 24 Hour Helpline at: 905-430-2522 or 1-800-452-0688.



Emergency Contraception: Birth control that is taken after sex to try to stop pregnancy, most often in the form of a pill known as the "morning after pill."

Needle Exchange: A program where injection drug users can turn in their used needles and syringes and get clean needles and syringes.

Prophylaxis: Treatment to stop a disease, in this case a drug to stop HIV infection.

Sexual assault: Any sexual act in which a person is threatened or forced to participate against his/her will.

**Portions of the PEP information on this website was reproduced with permission from the New York State Department of Health and the New York City Department of Health and Mental Hygiene.