'Expired' Medicines -- Are They Safe? - Medical Myths - Harvard Commentaries

My wife and I have this argument (she calls it a "discussion") several times a year. I serve up some perfectly good food of uncertain age from the refrigerator. She wants to throw it away. I say if the color looks right, it smells like food and tastes all right, we should eat it. She says better safe than sorry. And with that another perfectly good pasta dish (or was that chicken?) is tossed.

We have similar discussions about expired medications. I vaguely remembered hearing about a study that analyzed the potency and safety of the most common medications that were well past their expiration dates. The researchers found no evidence the medicines were harmful and most were still effective.

So, how are expiration dates set? And is it risky to take a medicine that is expired?

The study that came to mind was started by the U.S. Air Force in 1985. It was extended to other military services in the early 1990s. The military had gathered a stockpile of medications worth more than a billion dollars that were close to (or had exceeded) their expiration dates. No one wanted to throw away expensive medications that might still be safe and effective. So the drugs were extensively tested with oversight by the U.S. Food and Drug Administration (FDA).

The verdict? Most medications were still good nearly three years past their expiration dates.

So, I was right! Well, sort of. Before ignoring expiration dates on medications, there are a few caveats to keep in mind:

These tests of drug stability were in the mid-1980s and early 1990s. It's likely that newer medications have not been tested as well (or at all).

Only about 100 drugs were tested. And many were drugs that are rarely used by people who are not in the military. These included antidotes to chemical poisoning and antibiotics for malaria.

Some drugs did fail the stability test. Liquid antibiotics, nitroglycerin and insulin, for example, showed signs of physical decay. So, for these it's probably best not to use them past their manufacturer's expiration dates. Mefloquine, an antibiotic to prevent or treat malaria, and Epi-pens (injections of adrenaline for severe allergic reactions) also held up poorly past their expiration dates.

It's probably fine to take an allergy medication that's a month past its expiration date. But there is some risk in taking a heart rhythm medication that, if ineffective, could lead to an unstable and dangerous heart problem.

Medications kept in a cool, dry place are likely to last longer than those kept in a hot, damp place.

Since 1979, the FDA has required drug makers to give every medication an expiration date. And there must be some testing to come up with the time period.

Why couldn't the expiration dates extend farther into the future? A cynical view (and one that may be right!) is that drug companies set expiration dates to encourage us to replace our older medications (even if they are still good). The more we throw out, the more we'll need to buy to replace them.

Drug makers deny this. They say it would be too expensive to test a drug's stability over long periods of time, and in all the different conditions (for example, hot, cold, humid and dry) in which people keep their drugs.

Also, improvements in drug manufacturing and changes in drug information over time would require repeated "longevity" testing that would be impractical. Better, they say, to pick and stick with a shorter period of time they feel confident a drug will stay stable.

That might be acceptable if it weren't for the pharmacist who may reduce the expiration to one year from when the prescription is written! Some states require pharmacists to do this. This came from a 1985 recommendation from the U.S. Pharmacopeia, a not-for-profit group that establishes standards for drug makers.

What's the logic behind this? When a drug is taken out of its original container and put in a pharmacy canister, moisture and air can degrade the pills or capsules.

A patient's condition changes.

New drugs become available.

New information about drug interactions comes to light.

So, limiting the prescription to a year from when it's originally filled adds an extra level of safety. It requires the doctor to review whether continuing with the old medication beyond one year is still a good idea.

Even with the best of intentions, this conservative standard makes it even more likely that enormous amounts of perfectly good medications will be thrown away in this country each year.

All of this might make you want to think twice about getting rid of expired medications. However, getting rid of medications you no longer need could prevent many tragic injuries and deaths due to:

Abuse – An estimated 1 in 9 teenage kids abuses prescription pain killers; their supply is often their parents' medicine cabinet.

Accidental ingestion – A 2009 study from the Annals of Emergency Medicine noted that almost 10,000 young children accidentally took narcotic pain medications between 2003 and 2006.

Fatal poisoning – Medication is the top cause of deaths from poisoning, whether intentional or not.

Injury to pets – These family members are also at risk for ingesting your medications.

Believe it or not, there is a right way to get rid of unneeded or very old medications. Flushing them down the toilet turns out to be a bad idea: They can get into the drinking water supply.

Talk to your pharmacist and use an approved "drop off" location. Many places have a "take back" program once a year. You bring in medications you'd like to discard. If there is no such program near you and your pharmacist can't help you:

Put the medications in a sealed container (such as a coffee can).
Mix the medications with coffee grounds, mud or other disgusting material to discourage someone from ingesting them.
Mark out any identifying information on the medication container.

The next time my wife starts throwing out expired medications, I'll remind her that in the military study I mentioned above, the savings amounted to more than $260 million by keeping expired medications. We may not save that much. And we don't have the FDA to test and oversee extensions on our medicines' expiration dates. But there is a fair amount of evidence that if you store medications properly, they appear intact and are not one of the exceptions mentioned above, they are still safe to take.

For many common conditions, such as allergies, headaches or back pain, I'm willing to take the risk of applying my own, modest extension to the expiration date.

It's too bad that the mystery leftovers in the fridge don't come with an expiration date. But even if they did, I'd be tempted to stretch those, too.

Bailey JE, et al. "The underrecognized toll of prescription opioid abuse on young children." Annals of Emergency Medicine. 2009; Apr: 53(4):419-24.

Robert H. Shmerling, M.D. is associate physician at Beth Israel Deaconess Medical Center and associate professor at Harvard Medical School. He has been a practicing rheumatologist for over 20 years at Beth Israel Deaconess Medical Center. He is an active teacher in the Internal Medicine Residency Program, serving as the Robinson Firm Chief. He is also a teacher in the Rheumatology Fellowship Program.