Updated

Many of us are guilty of keeping leftover painkillers from a surgery or old injury in the medicine cabinet instead of throwing them out, but is it safe to reach for them months or years later when a headache becomes too much to bear?

We recently got this question from a viewer:

Hi Dr. Manny,

What really happens to medications on after their expiration date? Is it unsafe to still take them?

Thanks

The expiration date on a medication is the date when the manufacturer will guarantee the full potency and safety of the drug. However, a study requested by the military and conducted by the Food and Drug Administration (FDA), found that 90 percent of more than 100 drugs tested were safe to use up to 15 years after they had expired. The study included both over-the-counter and prescription drugs.

While the study seems to question the value of weight placed on expiration dates, it is important to remember what it signifies. While technically the medicines may still be potent, the effectiveness may not be the same. Additionally, taking expired medications can have fatal consequences.

Certain medications like nitroglycerin, insulin and liquid antibiotics are not as long-lasting as the ones that were tested in the study. A rule of thumb to live by is if you’re unsure about the safety of a medication and the expiration date has passed, throw it out or consult your local pharmacist before taking it.