The FDA started requiring drug companies to place expiration dates on drugs in 1978 on the reasonable grounds that people shouldn’t be using medicine so old it was no longer safe or effective. What the FDA didn’t do was set expiration dates, leaving that up to manufacturers. In 1985 the U.S. Pharmacopeia, a not-for-profit standards-setting body, began urging that medicines not sold in the manufacturer’s original container (that is, most medicines dispensed by pharmacists) have a one-year expiration date. The theory was that pharmacy pill bottles left in the notoriously hostile environment of your medicine cabinet (or, to be fair, a hot glove compartment) were less likely to prevent their contents from going bad.
But the truth is your meds will probably keep just fine. In the mid-80s the FDA started testing drugs as part of the U.S. military’s Shelf Life Extension Program — the Pentagon then had a $1 billion stockpile of drugs it didn’t feel like throwing out. As reported in that Wall Street Journal article in 2000, around 90 percent of the drugs were safe and effective well after they’d nominally expired .
To be sure, some drugs deteriorate faster than others. For example, epinephrine, used to treat cardiac arrest, steadily loses its potency over time. Liquid drugs and suspensions are less stable than solids. Medications custom-prepared by your local pharmacy are likely to have a short shelf life.
But even then it’s not like drugs go bad at the stroke of midnight. An update on the Shelf Life program published in 2009 established that 88 percent of tested medications worked fine more than five years past their expiration date, which admittedly just confirmed previous research. The more pertinent finding from a practical standpoint was this: one year post-expiration, every drug tested was still OK.
We were going to illustrate this post with a scene from Drugstore Cowboy (Gus Van Sant, 1989, Matt Dillon and his crew rob drugstores for drugs), but all the videos we found disallow embedding.