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Can an anti-viral medication prevent the transmission of HIV


I had unprotected sex with someone I later realized was hardcore heroine addict. He had a wristband on at the time telling me an elaborate story. He was actually covering all of his track marks and sores. After realizing this, I borrowed anti viral medication. Y the name of acyclovir. I've been taking 800mg a day for the past week after having intercourse with him. He did not cum inside me, but there could have been pre ejaculation that entered inside me. I also happened to be menstuarating and I am curious if that will have any effect on transmission. I am also curious if the acyclovir will help prevent transmission or is it too late?


Hi there, and thanks a lot for contacting the AIDS Vancouver Helpline for your HIV/AIDS related health information. It seems you're concerned about the possibility of HIV transmitting during an encounter. We're happy to answer your question for you.

Unprotected sex is considered a high risk activity. High risk means that of the transmissions that have been observed to occur, most have occurred due to activities such as these. To see the risk levels associated with many common activities, we encourage you to check out our risk assessment page. The fact that you were menstruating does not alter the risk level of this activity.

After a high risk encounter, PEP can be prescribed. PEP is a regimen of antiretrovirals that are meant to prevent a potential HIV infection from establishing itself. Unfortunately acyclovir is not a PEP medication, as PEP antivirals are specific for HIV. You are now past the 72 hour window period for PEP to be effective as well, unfortunately.

We'd encourage you to seek out a sexual health clinic in your area for more advice on what to do from here. You'll need testing to know your status 3 months post exposure.

We also encourage you to use a condom for all your encounters, as condom use substantially reduces the risk of transmission of HIV and STIs. For more information on protection, we encourage you to check out one of our favourite resources at SmartSex.

Thanks a lot for contacting the AIDS Vancouver Helpline with your question, we hope it has been answered fully.


AIDS Vancouver Helpline/Online