New Guidelines for Antiretroviral Therapy in Nonoccupational Postexposure Prophylaxis

In late January, the CDC released guidelines on the use of antiretroviral therapy in individuals possibly exposed to HIV through sexual intercourse, injection-drug use, or injury. These guidelines are not based on randomized trials, but rather on animal data, observational studies, case reports, and experience with occupational exposures among healthcare workers.

According to the guidelines, clinicians should first determine the individual's HIV status, the timing of the exposure, and the HIV status of the source of exposure. This information is then used to make decisions about therapy:

• Antiretroviral therapy should be initiated for 28 days in individuals who present within 72 hours of an exposure that involved "substantial" risk for HIV. Th…