Drugs’ expiration dates aren’t exactly absolutes

It’s midnight and you wake up with a hammering headache. You race to themedicine chest and, guess what. The only bottle of pain medicine you see haspassed its expiration date. What do you do?
Will expired drugs hurt you, or just result in pills that have lost all orpart of their potency?
These are questions that concern almost everybody and that led the AmericanMedical Association to investigate whether the shelf life of many drugs isreally longer than the posted expiration dates.
The short answer? Yes.
But experts on the subject can be confusing. Some ask whether the requiredexpiration dates could be a possible ploy to “keep you restocking yourmedicine cabinet and [drug company] pockets regularly. … You can look at itthat way,” said a 2003 Harvard Health newsletter published online.
But the paper quickly added, “Or you can also look at it this way: Theexpiration dates are very conservative to ensure you get everything you paidfor.”
The good news appears to be that there is little data that expired drugscan harm you, except by not giving you the strength needed for your condition.The one program that seems to be the gold standard on this issue is known asSLEP, the Shelf Life Extension Program, which has been administered by theFood and Drug Administration for the Department of Defense for 20 years.
“The SLEP data supports the assertion that many drug products, if properlystored, can be extended past the expiration date,” a recent report said.
The key, it turns out, is “properly stored.”
The lead investigator on the study, published earlier this year in theJournal of Pharmaceutical Sciences, Robbe C. Lyon, e-mailed some words ofcaution on using expired products.
“Although our studies have demonstrated that the actual shelf life of manydrug lots have greatly exceeded the labeled expiration, I still recommendstrict compliance with the labeled drug expiration dates. I have no confidencethat a specific bottle of medication in my possession will have anexceptionally long shelf life,” he wrote.
Why? “Keep in mind that all of the stability studies were done undercontrolled conditions with drug products sealed in their original containers.These results cannot be extrapolated to medications dispensed to patients andstored under variable conditions.”
In other words, when you open your vial of pills and leave it on thebathroom counter, you might be contributing to its degradation. And youcertainly aren’t storing your drugs with the concern and controlled conditionsused by the U.S. Department of Defense.
Yet, the Medical Letter on Drugs and Therapeutics said in its report in2002 that “many drugs stored under reasonable conditions retain 90 percent oftheir potency for at least five years after the expiration date on the label,and sometimes much longer.”
Because there is little information based on how most people store theirdrugs, the average pill-popper can’t really be assured of the quality ofdrugs, prescription or otherwise, beyond expiration dates.