Most of us have reached for a painkiller, at one time or another, only to discover the date on the label shows it has expired. But what does an "expiration" date on medicine really mean? Is it dangerous if you take it anyway? Less effective?
It turns out that date stamped on the label actually means a lot. It's based on scientific evidence gathered by the manufacturer showing how long the drug's potency lasts. Companies expose their medications to different environments, different temperatures and humidity levels to see just how long it takes for the medication to degrade to the point that its effectiveness is compromised.
The general rule, says pharmacist Mike Fossler, with the American College of Clinical Pharmacology, is that once a drug is degraded by 10 percent it has reached "the end of its useful life." If you take it months or even years past the expiration date, it's unlikely to do you any harm, he says; it just might not do you much good.
That may not be a big deal if you're treating a headache, but if you're fighting a bacterial infection with antibiotics like amoxicillin or ciprofloxacin, for example, using less than fully potent drugs could fail to treat the infection and lead to more serious illness.
Pharmacist Mohamed Jalloh, a spokesman for the American Pharmacists Association, says there's an even bigger reason not to rely on old drugs: antibiotic resistance. When you inadvertently "underdose" yourself by taking antibiotics that aren't full strength, he says, you run the risk that the bacteria you're battling will figure out not only how to defeat this weakened drug, but other antibiotics, too.
At least 23,000 people each year in the U.S. die from infections that have become resistant to antibiotics, according to the Centers for Disease Control and Prevention.
"If your medicine has expired, don't use it," concurs Ilisa Bernstein, deputy director of the office of compliance in the Food and Drug Administration's Center for Drug Evaluation and Research.
That goes for over-the-counter drugs, as well as prescription meds. Check the expiration date before even buying those pain relievers or allergy tablets, some pharmacists advise — the same way you check your milk. Buy the one with the date that's furthest away.
"Once the expiration date has passed," Bernstein says, "there is no guarantee that the medicine will be safe and effective."
Of course, even new drugs can quickly lose potency if they're not stored properly. Get those pills out of the bathroom "medicine cabinet" now, pharmacists say. The steam from your shower or shave kills pills fast.
"Medicines like the kind of environment that people like — a little dry and not too hot or cold," Fossler says. And, of course, don't take medication to the beach or leave it in a hot car. Like humidity, heat degrades a medicine's active ingredients.
Some medications are more vulnerable than others, so check the label. Insulin, certain immunotherapy drugs, and some children's pain relievers and cold remedies require refrigeration and protection from light.
And compared to capsules and tablets, "liquids are not as highly preserved," says Barbara Kochanowski, a scientist with the Consumer Healthcare Products Association. Liquid drugs can more easily become contaminated with bacteria and fungus.
Anytime you see a change in the color, odor or consistency of a drug — such as a cream turning into a runny solution — consider it a red flag, Kochanowski says, and consult your pharmacist. It's probably time to toss that medication.
Some drugstores, hospitals with pharmacies, drugmakers and drug-treatment centers have been authorized by the federal government, in recent years, to serve as "drug-take-back" sites for some drugs that are expired, or no longer needed. You can check the FDA and Drug Enforcement Agency websites for their latest guidance on the safest ways to dispose of various drugs.
DAVID GREENE, HOST:
And now a dilemma that most of us have probably experienced, reaching for a painkiller or other medication only to discover it's expired according to the date on the label. NPR's Patti Neighmond takes a look at what these dates actually mean.
PATTI NEIGHMOND, BYLINE: It turns out they mean a lot. Expiration dates are based on research showing how long the drug's potency lasts. Drug companies expose their medications to different environments, temperatures and humidity to see when a dose starts to degrade. Pharmacist Mike Fossler is with the American College of Clinical Pharmacology.
MIKE FOSSLER: After, about 10 percent of that dose is gone. That would be considered the end of the useful life of that drug. And then that would be your expiration date.
NEIGHMOND: If you take the drug months or even years past the expiration, it might not do you any harm. But it also might not do you any good, which may not be a big deal if you're treating a headache. But if you're fighting an infection with antibiotics, that could be a problem. In addition to keeping medication up to date, it's also important to store it properly.
FOSSLER: Medicines like the kind of environment that people like. We like it a little dry, and we don't like it too hot or too cold.
NEIGHMOND: Which means the place people often keep medications, the bathroom medicine cabinet, isn't a good idea because it's repeatedly doused with humidity.
FOSSLER: With your shower and things like that. So it's better to find a closet somewhere and keep your medicine.
NEIGHMOND: A dry, cool, dark place. Scientist Barbara Kochanowski with the Consumer Healthcare Products Association says this is particularly true for liquid medication.
BARBARA KOCHANOWSKI: That's often where you see refrigeration required or protection from light required. And anytime those conditions change, those medicines can rapidly degrade.
NEIGHMOND: And get contaminated with bacteria or fungus. If you see changes in color or consistency, those are red flags. Don't take it. So before you even buy the medication, check the expiration date and read the storage instructions on the label. That way, you'll get the most out of it.
Patti Neighmond, NPR News.
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