"Even 10 years after the "expiration date," most drugs have a good deal of their original potency. So wisdom dictates that if your life does depend on an expired drug, and you must have 100% or so of its original strength, you should probably toss it and get a refill, in accordance with the cliché, "better safe than sorry." If your life does not depend on an expired drug -- such as that for headache, hay fever, or menstrual cramps -- take it and see what happens."