When are expired medicines really expired?
NEW YORK — I don’t know about your medicine cabinet, but mine is a jumble of mostly expired drugs: the muscle relaxants I got when I threw my back a few years ago; the anti-nausea medicine that I never took during my stomach ailments last summer; Xanax to occasionally help me cope with the dizzying state of the world.
I often wondered what I should do with these expired medicines – if and how I should dispose of them, if they were unsafe to use or if some could still work perfectly. I dug into the research and contacted three prominent pharmacists, one of whom has studied expired drugs, to get some insight.
With guidance from the United States (US) Food and Drug Administration (FDA), manufacturers set drug expiration dates based on tests they have conducted to determine how long the drug will remain safe and efficient.
An expiration date “represents a promise that the drug is good for at least that long, if stored properly,” said Dan Sheridan, drug safety pharmacist at OhioHealth Marion General Hospital. Many expiration dates are set between one and five years after the drug is manufactured.
For many prescription medications, however, what you see on your bottle is not an expiration date, but an “out of use” date. (On my prescriptions, that date appears after the words “Discard by.”) The expiration date is usually earlier than the drug’s original expiration date, explained James Stevenson, a pharmacist at the University of Michigan College. of Pharmacy and Chief Clinical Officer of healthcare technology company Omnicell. This is because a pharmacist often has to manipulate, mix with other ingredients and move a medicine into a new container in order to give it to you, which reduces the duration of use, he said.
For some drugs, the expiry date is only a few days or weeks after the drug is dispensed. “A powdered antibiotic suspension may be good on the pharmacy shelf for two years, but only for 14 days once the pharmacy adds water and dispenses it to the patient,” Sheridan explained.
Although expiration and beyond use dates provide useful information – you can be sure that your medicine will work for at least that long if it has been properly stored (more on that in a minute) – the drugs don’t necessarily become dangerous or less potent once that date has passed, said Dr. Lee Cantrell, clinical pharmacist at the University of California San Francisco School of Pharmacy.
In a small 2012 study, Dr. Cantrell and three colleagues tested eight drugs, containing 14 very different active ingredients, that had been sitting unopened in a pharmacy cupboard with expiry dates that had passed between 28 and 40 years earlier. . They found that 86% of the drug ingredients were still present at the concentrations they were supposed to be. The results suggest that some drugs, like acetaminophen and the opioid painkiller hydrocodone, retain their potency “for a very, very long time,” he said.
Dr. Cantrell stressed, however, that he and his colleagues had not actually tested the drugs on people. “I can’t say it’s OK to take expired medicine,” he said. The FDA also recommends not taking expired medications. However, he has worked at the California Poison Control Center in San Diego for nearly 30 years and said people regularly call the center after realizing they’ve taken expired medication, worried about what will happen. To his knowledge, nothing wrong has ever happened, he said.
Dr. Cantrell’s study is one of the few published studies that have assessed the chemistry of expired drugs. In a study published in 2006, researchers from the FDA and the pharmaceutical company Sandoz tested 122 pharmaceutical products and found that 88% were still safe to use an average of 5.5 years after their expiration date.
In fact, the FDA sometimes tests expired drugs needed for public health emergencies and extends their expiration date if they are found to work and are safe.
When considering taking expired medicine, use common sense. It is safer to take an expired medicine to treat a health nuisance – like ibuprofen to relieve a headache or an allergy medicine to treat mild hay fever – than to take one to treat a serious illness, Dr. Cantrell said.
Antibiotics belong to a class of drugs that you should not use after the expiry date, Stevenson said. If you take an antibiotic that’s not as strong as it should be, “it might actually be harmful,” he said, because the medicine might not fight your infection effectively. Research from the 1960s also linked expired tetracycline to kidney problems, possibly because the antibiotic produces dangerous chemicals when it breaks down, but it’s unclear if current formulations have this risk.
Mr Sheridan also warned against using expired eye drops – they can be contaminated with micro-organisms; and stale nitroglycerin, as the explosive that is also used to treat chest pain in people with heart disease loses potency over time. The American Diabetes Association also does not recommend using insulin past its expiration date.
Most medications can be thrown in the trash, but the FDA recommends mixing them with coffee grounds, dirt, or kitty litter so they’re less appealing to children or pets who might consider to eat them, and let them be sealed in a bag or container. Some drugs that have abuse potential, including those that contain opioids, should not be discarded.
According to the FDA, these drugs can be flushed down the toilet, but the Environmental Protection Agency warns that this can lead to contamination of drinking water, rivers and lakes, as many water treatment plants are not not equipped to dispose of drugs. Mr Sheridan instead recommended depositing medications in secure medication disposal boxes found in pharmacies. In addition, the Drug Enforcement Administration partners with local governments to collect drugs at events designated “National Prescription Drug Recovery Day.”
This article originally appeared in The New York Times.