Is it safe to take expired medication?

This story has been updated. It was originally published on September 12, 2017.

The bottle of NyQuil always seems to be grimy, faded, and buried beneath layers of toiletries when you come down with a sudden cold. Tired and sniffling, you peer at the label. The medication expired six months ago. At that moment, it’s easy to question the number printed on the bottle: How solid is that expiration date, exactly?

Gina Bellottie, a professor of pharmacology at Thomas Jefferson University in Philadelphia, says that, as a general rule, people shouldn’t take drugs past their…