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False test?

Wondering if I can get some clarity here: 8 months ago I had an encounter at a bar. It was dark and I was drunk and I can’t remember if I used a condom for vaginal sex. I got tested at 7 months with a fourth generation test. The result was negative. I was taking doxycycline for my acne at the time. I want to know if there’s any chance my hiv test was affected by a 200mg dose? I ask because doxycycline also treats STDs. Moreover I was looking to find answers on google and I came across this which says drug interference was checked for the following drugs and I’m very surprised to see there’s so many meds on the list like ascorbic acid, paracetamol, ibuprofen etc and even doxycycline and possible interferences of these drugs was tested but the concentrations tested are listed and I’m afraid I was taking more than 50 mg of doxycycline! They didn’t test more than 50mg which means as I was faking 200mg a day is my test wrong? I also remember taking a paracetamol couple hours before my test! Do these medicines affect hiv tests? What should I do now? What a bother! And if they don’t interfere than why does this tests package insert suggest they do? https://www.fda.gov/media/105906/download
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Avatar universal
Your test would have been conclusive after 4 weeks so it doesn't matter what you're on after 7 months. It is time to move on.
5 Comments
The question is about the antibiotic interfering with the test not about whether it would affect my body’s ability to make antibodies. Please can you read the link, it really says they tested 50 mg doxycylines affect on the Roche combo test which is what I took. That dosage doesn’t affect the test, but since I was on 200mg will that affect the test? Again I am asking about the affect on the test not my body. Also I took paracetamol and even that is listed as affecting the test. I took 1000mg and this fda link says they tested only up to 200mg. I don’t know what to do now. I guess my test is not accurate!
Please read page 9 & 10 of this link https://www.fda.gov/media/136857/download
That doesn't say what you think it says AT ALL.  That's mg/L, not how much a person took.  If you don't have laboratory expertise, you should stop reading and trying to interpret laboratory guidelines.

HIV tests are among the most accurate tests for any disease on the market.  That would not be so if every med a person might likely be taking interfered with test accuracy.  Experts in the field consistently say that the only drugs that *might* produce a false negative are heavy chemotherapy drugs for cancer treatment that gravely suppress the immune system.  If you don't believe HIV expert physicians, you're not likely to believe us either, so this will be my last word on the subject.

Call the laboratory if you have further questions about your test.
Are you certain that mg is different from mg/l? If I am right and that is 50mg and I was taking 200mg, do you think my test is wrong? Sorry but I am very panicked and I don’t know who to ask or who to turn to :(
Your panic is irrational. Most people aren't HIV+, so it's likely your partner was not.  Even IF your partner was positive, the odds for a man who has a one-time unprotected vaginal event are 0.04% - a 99.6% of NOT getting HIV.  

The "per liter" indicates concentration in bodily fluids.  Your test results are conclusive.  Any panic you are having is contrary to medical science.
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