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On PREP but Indeterminate 4th Generation Positive Test

Dec 16, 2017

Hi Damon,

I have been on PREP for more than a year. I have only had anal sex without a condom once, more than four months ago and I suspect my partner did not ejaculate in me. I haven't had anyone insert their penis in me since then, and I haven't topped anyone.

At my routine PREP visit (the second PREP visit since having condomless anal sex), my rapid came back negative but the 4th generation came up indeterminate. I have done two more followups in the past two weeks. My doctor did two different rapids and two more 4th generations. The rapids came back negative; the 4th generations came back indeterminate. My doctor says I should test again in a month and that he is treating me as if I am negative because of the rapids.

Do you have any advice on what is going on with the indeterminate results?

Response from Mr. Jacobs

Hi There,

Thank you for writing in and asking about this traumatic, but sadly not uncommon experience. First and foremost, it's important for you to know that "indeterminate" does not automatically equal "HIV positive." There are many reasons why one may return an indeterminate test result even whey they are HIV negative ( ;

Anecdotally, I can tell you that I have two friends who use PrEP and at some point received an indeterminate HIV test result. In both cases, the next tests showed HIV negative and have been negative ever since.

Why is this happening and is it more likely to happen with PrEP consumers? Honestly, there are no clear answers. What's most important is that you and your doctor continue to test, as you are doing, and figure out exactly what is going on.

Based on the activities you described, you have been put at no risk of acquiring HIV. You said you had one event of receptive condomless anal sex, and he did not ejaculate. Even if he had a detectable (transmittable) level of HIV, and even if he did ejaculate inside you, the likelihood of acquiring HIV from just one encounter is exceedingly rare (

My question to you is - are you sure you need to be on daily PrEP? If you are only sexually active once a year, and if you can reasonably plan for sexual events ahead of time, perhaps you may wish to discuss with your provider the option of using PrEP for "event-based" dosing. This involves using fewer pills before and after a scheduled sexual event ( Although the U.S. CDC has yet to endorse this regiment, it is being used more widely in parts of Europe and Canada, with seemingly little complications.

I do hope this information allows you to relax and understand how to proceed forward. Please do let us know how things go here at The Body.

Bottomed with someone who is on PrEP
Anal Rubbing?

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