Expired Medications – Are They Safe?
What does that expiration date on the medication bottle mean, anyway? The Medical Letter, a well-respected publication, addressed this topic in 2002, then again in 2009. In reading those two reports, it seems the answer to the question is, "it depends". As a general rule, pills stored in their original, unopened bottle have the best chance of maintaining potency for several years past the expiration date. In fact, the expiration date is basically the date the manufacturer puts on the bottle to say "we guarantee >90% potency up until this date". After the expiration date, the usual thing that occurs is nothing. Medications don't suddenly lose all of their potency, nor do they become suddenly dangerous. We don't recommend using eye drops past their expiration date, but that's because the preservative that keeps your eye from getting infected may no longer be active.
The military was buying and throwing away millions of unused prescription items every year based on label expiration dates. They hired the FDA to do a study to determine what the actual date should be beyond which not to use them. Even when stored under high heat and humidity, which should lead to breakdown, many medications tested were still good for 2-5 years past their expiration date. Some of them were good 25 years past their expiration date! Another general rule: liquids don't last as long as powders, pills or capsules. Suspensions are very prone to freezing, which can upset their chemical structure.
We prescribe an EpiPen for each patient on allergy shots, but those EpiPens are only used if the patient has a serious reaction to their allergy shot. Thus, many expire without ever being used. Expired EpiPens have been studied for potency and there is a clear observation that the older the EpiPen is, the less helpful it would be in case of emergency. Bottom line for EpiPens –keep them only until their expiration date, then replace them. But, if all you have is an expired EpiPen, go ahead and use it. Then call 911. Be sure to replace expired eye drops and liquid medicine. As for over-the-counter cold preparations or Tylenol—they're probably safe to use for a few years after the expiration date.
Note: Information contained in this article should not be considered a substitute for consultation with a board-certified allergist to address individual medical needs.