Updated HIV Post Exposure Prophylaxis (PEP) Guidelines


I recently got stuck with a needle which was in an HIV positive patient's gum. The needle did not have any associated blood. Would you recommend prophylactic AZT in such a case?


Hi. Thank you for your question. When deciding on whether HIV Post Exposure Prophylaxis (PEP) is indicated in a specific case, you need to ask yourself the following questions:

  1. Was the patient KNOWN to be HIV positive or KNOWN to be at high risk of infection?

  2. Were you directly exposed to a significant quantity of a high risk body fluid (for example blood, semen, etc.)?

  3. Was there a significant chance of the virus entering your bloodstream?

If the answer was "yes" to all 3 questions, then PEP is considered. To determine if PEP is recommended after an exposure, read the table, "Determining the need for HIV postexposure prophylaxis (PEP) after an occupational exposure" in the "Public Health Service Guidelines for the Management of Health-Care Worker Exposures to HIV and Recommendations for Postexposure Prophylaxis." This table cannot be applied to every single situation, but is a good general guide to follow. PEP is generally not recommended for low risk exposures, source patients who test HIV negative, or source patients who are not at high risk of infection. If you were not exposed to the patients blood or other risky body fluids, then PEP is normally not recommended.

PEP should be started preferably within several hours after an exposure, and continue for 4 weeks. Beginning PEP after 24-36 hours may not be as effective, but may be considered if it is not possible to begin treatment sooner. Beginning PEP after 1-2 weeks may not prevent infection, but may have a clinical benefit for those that become infected after a very high risk exposure. There are many variables that determine whether PEP should be used, and which drugs should be used. The decision as to whether PEP is necessary or not, and which drugs to use, needs to be taken on a case-by-case basis. For more information on PEP for occupational exposures, read the following reference:

Morbidity & Mortality Weekly Report