You've rummaged through your medicine cabinet and found a COVID test... but wait, it's expired. Now what? Do expired COVID tests work, or are you better off just throwing it away? The short answer: it's complicated.
Manufacturers assign expiration dates based on stability studies. These dates guarantee accuracy up to that point. However, test components might still be effective beyond that date. The FDA has even extended expiration dates for some tests after further evaluation.
Using an expired test carries risk. The reagents might degrade, leading to false negatives (thinking you're negative when you're actually positive) or false positives (the opposite!). If you *must* use an expired test, consider it less reliable. Ideally, obtain a new, unexpired test for accurate results, especially if you're symptomatic or have been exposed. When in doubt, err on the side of caution and prioritize a fresh test.
