Which of the following correctly describes the expiration date of a drug?

The expiration date of a drug refers specifically to the last day of the month indicated on the packaging. This means that a medication is considered effective and safe to use up until that date. Therefore, if a drug is labeled with an expiration date of, for example, April 2023, it should be good until the last day of April, which is April 30, 2023.

Understanding expiration dates is crucial in pharmacy practice, as administering medications beyond this date may pose safety risks and reduce efficacy. Properly interpreting expiration dates helps ensure that patients receive effective and safe medication.