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PEP Effectiveness and Correct Dosage?


After an exposure, I started taking PEP around 20 hours from the time of exposure. I was wondering how effective it would be on preventing an HIV infection, are there any studies done?

As well, I realized that I may have not taken it "correctly"? I was given two drugs, Truvada and Isentress, and I was instructed by the pharmacist to take 1 Truvada and 2 tablets of Isentress daily for 30 days. I usually took the one tablet of Isentress from around 8-9am, with the Truvada and Isentress combo from around 5-6pm. Was I supposed to exactly take them 12 hours apart? Will this reduce the effectiveness of the PEP treatment?

2 Responses
Avatar universal
86% effective. Your second dose of Isentress should be 12 hours after your first dose.
Avatar universal
I finished my 30 days and used that 8:30am, 5:30pm schedule.

I should have researched more online, as the pharmacist did not specify that it had to be 12 hours apart. Is this very concerning? If it is any help, I was very strict on that schedule.

Thanks once again
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