As discussed in Just What Is a Medication Expiration Date, an expiration date is the point at which a manufacturer can no longer guarantee the strength or safety of a medication. Because this date is established by testing a drug in specific conditions related to storage containers, lighting, temperature, etc., this date, as per the US Food and Drug Administration (FDA), is compromised by changing any of these conditions. This includes moving a medication to a different container –- the normal practice for pharmacies dispensing prescriptions.
Because of this, the US Pharmacopeia –- the official public standards-setting authority for all prescription and over-the-counter medicines and other health care products manufactured or sold in the United States –- recommends the practice of beyond-use dates.
- The beyond-use date placed on the label shall be no later than the expiration date on the manufacturer’s container. The beyond-use date is a date after which an article [drug] must not be used. Based on the information supplied by the manufacturer, the dispenser shall place on the label of the prescription container a suitable beyond-use date to limit the patient’s use of the article (AMA, 2008).
So ... wondering when you should toss your prescriptions and pick up new ones? We discuss this in detail in When Do Medications Actually Expire?
References
American Medical Association. (2008, February). Report 1 of the Council on Scientific Affairs (A001): Pharmaceutical expiration dates.

