[Question #7833] Potentially expired home test

6 days ago

I bought a rapid home HIV test (Autotest VIH by Sante) in Europe 8 months ago, for use if i needed it in future. Its billed as a second generation test.  I didn’t note the expiry date on it when bought but im sure it was in date as i bought from a reputable pharmacy. As a space saving measure i removed the test from its box and have been carrying the test in just its sealed foil pouch since. Unfortunately due to this, the lot number , manufacture date and expiry date rubbed off over time so i cant be sure of the exact expiry date. I believe the tests have an 18 month or so shelf life, but i was wondering how quickly the reliability of such test diminishes with time?. I just used the test and got a negative result and the test appeared to work perfectly. The foil pouch was still fully airtight before i opened it. Also, Im now in a country where i cant buy another home test. 


So best case the test was in date and i have nothing to worry about, worst case the test was 7 or 8 months out of date. What are primary risks from using a test that may be slightly out of date? Can i trust the negative result at all?


Grateful for your opinions.

H. Hunter Handsfield, MD
H. Hunter Handsfield, MD
5 days ago
Welcome to the forum and thanks for your question.

I have no experience with that particular test, but very probably the result is valid. Expiration dates on test kits (and on pharmaceuticals, like prescription drugs) are very conservative. If a company tests a product at, say, 2 years after production and it works propertly, regulatory agencies (such as the US FDA and its equivalents in the EU, UK, and other countries) require 2 years to be stated as the expiry date. That doesn't mean the test isn't valid after that time, only that it hasn't been tested. In most cases, the reagents (or active ingredients in drug products) are highly stable. In addition, it would be surprising if it didn't have at least a year to go before it was sold. Most pharmacies would not have a product on the shelf that was going to expire in the near future.

So probalby your negative result is accurate. But if you remain uncertain, the only solution is to be retested.

I hope this has been helpful. Let me know if anything isn't clear.

HHH, MD
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2 days ago
Thanks for your reply and for explaining the logic of why the test result is very likely valid. Yes, the control line showed up very sharply which would indicate at least the reagents at that location were still good. Would this further suggest the reagents at the test line would have been in good condition also?

I will test again in about a month, which is the next time it will be convenient to do so for me. Given i took the above test 6 weeks after unprotected intercourse with female of unknown status i assume you don't expect the result to change?



H. Hunter Handsfield, MD
H. Hunter Handsfield, MD
2 days ago
The control line proves the test was working properly. Sorry I didn't think, to mention this in my reply.---
2 days ago
Ok, thats good news! 

Final clarification, is there any way the reagents at the test line could be less stable than those at the control line?


H. Hunter Handsfield, MD
H. Hunter Handsfield, MD
2 days ago
To my knowledge, no -- the reagents at the two sites undoubtedly to not deteriorate at different rates.

Perhaps you'd like to know that in the 15 years of this a our preceding forum at MedHelp, with thousands of questions about HIV risk and test results, not one person has turned out to have acquired HIV. I'm confident you won't be the first! You don't say the nature of your exposure and level of risk, but I'm confident that if and when someone reports they actually were infected, it will be a truly high risk event -- like unprotected anal with a known infected partner. If your exposure was heterosexual, for example, plus this negative result, there is no realistic chance you were infected.

That completes the two follow-up exchanges included with each question and so ends this thread. I hope the discussion has been helpful.
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