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Not Taking PrEP Correctly?

Apr 16, 2017

A friend of mine did not follow guidelines before having unprotected sex. He took two tablets 30 hours before sex and then again 1 hour before having sex. what are the risk of catching HIv. What treatment should he follow. He has taken one more tablet 12 hours after.

Response from Mr. Jacobs

HI there - Your friend is fortunate to have you looking out for him. The approved regimen for taking PrEP varies a bit by geographical regions. In the United States, daily use is the recommended protocol by the CDC. (

However, in other parts of the world, the intermittent dosage strategy tested in the "Ipergay" trial is often recommended. This is a regimen that involves taking 2 doses of Truvada anywhere from 2 to 24 hours prior to any potential HIV exposure, than 1 dose 24 hours later, and another dose 48 hours later, and then daily if potential exposures are ongoing. (

In the case of your friend, it sounds like he is loosely following the Ipergay protocol, but not exactly. It is quite possible that 2 tablets 30 hours before sex, and then one hour before sex may protect, but that wasn't measured in these trials. Also, taking only one dose following a potential exposure may provide protection, but whether or not it is sufficient enough wasn't studied.

I'd highly encourage your friend to sit down with his provider and figure out a proven workable plan to take PrEP that will maximize his protection. What he is doing now is not a proven strategy, and could result in acquiring HIV if exposed to a detectable viral load. If either you, or him, want to learn more about PrEP and dosing regimens, feel free to check out the international Facebook group page at "PrEP Facts: Rethinking HIV Prevention and Sex" (

Conceive Naturally with PreP?
Unprotected sex with someone on Prep?

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