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Ask Dr. K

I recently received oral sex from an HIV infected person. My doctor told me that the risk of transmission was low, but he put me on the PEP anyway. I completed 22 days of the 28 cycle. My 1-month test indicated I was HIV-. Should I still be worried?

PEP, or Post-Exposure Prophylaxis (prevention) is the use of combination anti-HIV medication after an exposure to HIV. It is important to finish the entire 28-day PEP cycle, rather than stopping partway through. Studies in health care workers who have been exposed to HIV from a needle stick and in animals exposed to HIV experimentally show that PEP works best when used for the full 28 days. Receiving oral sex from an HIV infected person is indeed an extremely low risk behavior and while most places do not recommend the routine use of PEP after oral sex. A negative 1-month test is a reassuring sign but not definite unless it was an RNA test, which actually measures the virus. If the test was the more common antibody test, it is important to take the 3-month test to be certain. After a negative 3-month test, a patient should be able to rest easy.

For more information on PEP, please see [] and scroll down to the section on PEP.

Please see a similar question:

To your health,
Dr. K

Last modified on Thursday, November 19, 2009.
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