As a nursing student, I learned about the 5 rights that you must always check before giving a medication to a patient: right patient, right medication, right dose, right time, and right documentation.
Two additional rights that my Adult and Elder I simulation instructor emphasized was allergies and expiration dates.
Today, I rubbed on hydrocortisone 1% for my mosquito bite. Instead of soothing, my bites started to burn. I checked the expiration date after the fact (oops) and saw that it expired in 2007. Honestly, I don’t know how I still have medication from that long ago, but I threw it out right away. So the bottom line is: CHECK THE EXPIRATION DATE before applying, injecting, or ingesting any drug.