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Post-Exposure Prophylaxis (PEP) for HIV


Download Facts about PEP for HIV

PEP for HIV facts

Post-exposure Prophylaxis (PEP) for HIV is an approach to preventing HIV infection after a possible exposure to HIV. Prophylaxis means disease prevention. PEP for HIV involves starting HIV medications as soon as possible after an HIV exposure.

How does PEP prevent HIV?

PEP limits HIV’s ability to divide and spread itself inside a person’s body. It is very important to start PEP as soon as possible, but always within 72 hours after an exposure.

  • PEP is not a “morning-after” pill. It involves taking several medicines, once or more a day, for at least 30 days.
  • Missing a dose may reduce PEP’s ability to prevent HIV infection.
  • Missing doses may also enable the virus to develop resistance if the person becomes HIV infected. This means that the medication may no longer work for the individual taking it.

Who should use PEP?

PEP should be used by anyone who thinks they have been exposed to HIV. People may be exposed to HIV in many ways:

  • On the job, such as through an accidental needle stick (healthcare workers).
  • From sexual assault.
  • During unprotected sex.
  • By sharing needles while injecting drugs.

Individuals who have experienced repeated HIV exposures outside of a healthcare setting should consider HIV pre-exposure prophylaxis (PrEP). PrEP is an effective prevention option that reduces the risk of HIV infection.

Does PEP guarantee an individual won't get HIV?

No, unfortunately PEP is not 100 percent effective. It does not guarantee that someone exposed to HIV will not become infected with the virus.

When should PEP be given?

  • To be effective, PEP must begin within 72 hours of exposure. After this time HIV infection is established and cannot be prevented.
  • Treatment should continue for four weeks.
  • If 72 hours have already passed, an individual should seek HIV counseling and testing services.

What should an individual expect when coming in for PEP?

  • Intake interview and counseling.
  • A discussion about whether PEP is needed.
  • Testing for HIV and STDs.
  • If needed, taking medication every day for a month.
  • Follow up HIV testing after completing PEP.

Is PEP covered by insurance?

Yes, most insurance and Colorado Medicaid cover the cost minus a co-pay and your deductible.

Are there side effects to taking PEP for HIV?

The most common side effects from PEP medications are nausea, headaches, fatigue, vomiting and diarrhea. These can be treated and are not life-threatening. The benefits of continuing PEP to prevent HIV outweigh the discomfort from these side effects.

Who to contact to access PEP

During the week (Monday – Friday)

Nights and Weekends

  • Contact your primary care provider or seek care in a local emergency room or urgent care setting.

Additional Resources

The Center for Positive Health Contact Information

The Center for Positive Health: HIV Services at Denver Public Health

Monday through Friday

8 am - 5 pm

605 Bannock St., 5th Floor
Denver, CO 80204-4507
Email Us
(303) 602-8710

HIV Dental Clinic

Monday through Thursday

8 am - 5 pm

(303) 602-8713
Email Us

Public Health Pharmacy
Refills (303) 602-8762

Monday through Friday
8 am - 5:30 pm

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