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You don't necessarily have to throw away that at-home COVID-19 test just because the expiration date on the package has passed.
Sometimes the U.S. Food and Drug Administration extends expiration dates after the packages have been shipped because new information on the product's stability has been obtained.
"An extended expiration date means the manufacturer provided data showing that the shelf-life is longer than was known when the test was first authorized," the FDA says.
To find out if your home test's expiration date has been extended, go to this FDA website and look for the name of your test. You'll need the lot number printed on the box. The first expiration date may be inside the box, on the some of the test parts.
If the expiration date has been extended, you should be able to find the old and new dates. If there's no new expiration date, the date on the package is still valid, the FDA says
The FDA says that COVID test makers have two ways of determining whether a product has expired, called stability testing.
In real-time testing, the manufacturer stores tests for the same amount of time as a proposed expiration date. If the manufacturer goes with a 12-month expiration date, they will check the test's ability to perform accurately after 13 months of storage, the FDA says.
Accelerated testing allows manufacturers to save time when a product must be rushed onto the market. Tests are stored for shorter time periods at higher temperatures and then evaluated. The FDA says accelerated testing usually gives "sufficient assurance to label tests with a shelf-life of up to six months."
What happens if you use a test that has really passed all expiration dates?
Jamie Alan, Ph.D., associate professor of pharmacology and toxicology at Michigan State University, told Prevention that you're more likely to get a false negative.
"The test might be negative because the reagents or ‘ingredients' are past their shelf life and are not working as they should," she said. "If you get a positive, you are probably positive. If you get a negative, it would be good to follow up with another test, either a PCR test or another rapid at-home test."
FDA: "At-Home OTC COVID-19 Diagnostic Tests"
FDA: "At-Home COVID-19 Diagnostic Tests: Frequently Asked Questions"
Prevention: "Do Expired COVID Tests Work? Here’s the Deal, According to Experts"
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Cite this: Has Your COVID Test Really Expired? - Medscape - Nov 29, 2022.