Pre-exposure prophylaxis, or PrEP, is the first medicine approved by the Food and Drug Administration that has been shown to be effective for preventing HIV infection.

UCLA researchers reviewed major studies of PrEP for preventing HIV prevention and aspirin for preventing heart attack. They found that both had similar low rates of serious side effects. Aspirin users rarely had serious bleeding or death and PrEP users rarely had serious kidney or bone damage.

Nearly 50,000 people in the U.S. are newly diagnosed with HIV every year. Many doctors have been worried about prescribing PrEP for safety reasons.

PrEP has been shown to work very well to prevent HIV when taken every day.

With the study showing that PrEP might be as safe as aspirin, doctors should feel more comfortable prescribing it, and patients should feel more comfortable using it. The data also could support efforts to make PrEP available without a prescription as an over-the-counter medication.

The study was funded by the UCLA Center for AIDS Research and UCLA AIDS Institute.

Research: Is Emtricitabine-Tenofovir Disoproxil Fumarate Pre-Exposure Prophylaxis for the Prevention of HIV Infection Safer than Aspirin? Noah Kojima and Jeffrey D. Klausner, Open Forum Infect Diseases, doi: 10.1093/ofid/ofv221, published online 6 January 2016.