(LifeWire) - If you're like most consumers, the drugs in your medicine cabinet have been there long past the expiration dates on their labels. But is it necessary to throw them all out when the ``Do Not Use After'' date has passed? The answer, quite often, is no.
Many drugs are still safe and effective as much as 15 years after their expiration date, according to research conducted since the 1980s by the Food and Drug Administration and the military, which has immense stockpiles of drugs to purchase, maintain and replace. Of the more than 100 drugs tested years after their expiration dates, 90% were found to have full potency.
American drug makers have been required since 1979 to label their products with a date up to which they will guarantee the drug's potency; this date is generally 2 to 3 years after it was manufactured. But the American Medical Association has determined that there is "little scientific basis" for these dates.
So are all medicines still good years after their expiration dates? No, some drugs, such as insulin, nitroglycerin and certain antibiotics need to be used by their expiration date or safely discarded. The epinephrine in EpiPen injections -- used to treat severe allergic reactions -- should also not be used after its expiration date.
Proper storage of drugs is probably the most critical factor in long-term drug safety and potency. It's important to remember that the aforementioned drugs tested by the FDA and the military were stored under exacting laboratory conditions. Ironically, your bathroom's medicine chest may be one of the worst places in your home to store drugs, as temperature changes and humidity from showers can quickly degrade drugs. The same holds true for storing drugs in kitchen cabinets, where dishwasher steam and hot air from cooking appliances may diminish potency.
Store your drugs away from children and pets in a dark area where the temperatures are cool and stable, such as a dresser drawer. Your refrigerator might be an ideal storage environment if dampness is not a factor. Don't mix different drugs in one container, and make sure all caps and lids are securely sealed.
In general, pills and capsules are more stable than drugs in liquid form, but if pills have turned powdery, are discolored or have a strong smell, they should be discarded. Similarly, avoid using any medicated liquids that are cloudy or filmy, or creams that are cracked or hardened.
And if you're unsure whether a particular drug is safe to use after its expiration date, your best source for information is your doctor or pharmacist.
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