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Health

Mixing prescriptions and over-the-counter medicines can be dangerous—especially for older adults. Here’s how to protect your health

By
Liz Seegert
Liz Seegert
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By
Liz Seegert
Liz Seegert
Down Arrow Button Icon
February 1, 2023, 6:00 AM ET
Senior woman taking medicine from pill box.
Mixing medications and supplements can cause serious damage to your health. Getty images

From pain relievers and cold pills, to vitamins and sleep aids, many products you buy at your local drugstore can have harmful health consequences as you age. Older adults absorb and metabolize medications differently from younger people, which affects how they work in the body. Even seemingly harmless over-the-counter (OTC) medicines can interfere with prescription medications, making them less effective and possibly leading to long-term health damage.

How to know what’s safe and what’s not

“Many people think that just because certain drugs are sold without a prescription, they’re safe,” says Patty Slattum, a geriatric clinical pharmacologist and director of the Geriatric Pharmacotherapy Program at Virginia Commonwealth University. “Not only does aging change the way our bodies process medication, but when used chronically or in combination with other medications, that’s when we see problems occur.”

Approximately 83% of U.S. adults in their sixties and seventies used at least one prescription drug in the last 30 days, and about one-third used five or more prescription drugs, most commonly for cholesterol, high blood pressure, and diabetes, according to the Centers for Disease Control and Prevention.

However, many seniors also take nonprescription products for everything from arthritis pain to constipation, and they’re not always discussing their use with a physician or pharmacist. A report from Northwestern University found that while 86% of patients think their doctor knows about all the over-the-counter medicines they take regularly, only 46% say they actually had a conversation about these products.

When mixed with prescription drugs, active ingredients in cold, allergy, and other common medications can be recipe for serious problems. “You can take too much and not realize it, causing other medication to be less effective and potentially leading to organ damage if this happens regularly,” says Slattum.

Hidden side effects

Common pain relievers, like ibuprofen or aspirin, alone or in combination with other medication, can lead to increased risk of bleeding, stomach, and kidney problems. Antihistamines, decongestants, and sleep aids can affect memory, and cause dry mouth and urinary retention. These products may also cause daytime drowsiness, leading to balance problems and increased fall risk. Decongestants can also raise blood pressure, and can interfere with sodium excretion.

“Our brain becomes more sensitive to many of these ingredients, and that can lead to what some have described as a hangover effect and confusion the next day,” Slattum says.

Certain vitamins and mineral supplements can also be harmful. Either people can take too much, leading to toxicity; or they can interfere with the effectiveness of prescription medications.

Too much vitamin A can lead to weakened bones; excessive doses of vitamin B6 can increase risk of neurological problems; and too much vitamin B12 can narrow coronary arteries. Since both aging and certain prescription drugs can affect a person’s ability to absorb key nutrients from food, it’s best to use any vitamins or supplements under a doctor’s guidance.

Other health issues may come from Zinc, which is found in many cold medications and denture adhesives. In high doses, it can affect immune function, and is linked to higher risk of prostate cancer. Vitamin D supplements, recommended for many older people who don’t get enough naturally, is linked to kidney stones, irregular heart rhythms, and confusion when taken in excess.

Be aware of “natural” products

What about the “natural” herbal products? “Natural does not always mean safe,” says Melinda Hemmelgarn, a registered dietician and former state nutrition specialist with the University of Missouri Extension program.

“Just because a product is for sale does not mean it’s been tested for either effectiveness or safety, including the presence of contaminants. Even with a master’s degree in human nutrition, I find the supplement shelves to be overwhelming,” says Hemmelgarn, host of the Food Sleuth Radio show.

Some botanicals and herbs can cause serious harm if taken with certain prescription medications—such as increased risk of bleeding in those taking blood thinners, or interference with insulin levels. Some slow down the absorption processes in your body and can actually increase the amount of that drug in your system, according to the National Center for Complimentary and Integrative Health.

The FDA does not approve dietary supplements for safety and effectiveness before they’re sold to the public. It’s up to manufacturers to ensure their products meet safety standards and are not otherwise in violation of the law. “So, it’s buyer beware,” Hemmelgarn says.

The best advice is to consult your doctor or pharmacist before taking any medication and make sure everyone is in the loop about what you’re taking, regardless of whether it’s by prescription or sold over the counter.

“Not every potential side effect or warning can be put on a tiny label, and the list of active and inactive ingredients can be confusing,” Slattum says. “We can help you find alternatives that will minimize risk and avoid potentially serious health problems.”

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By Liz Seegert
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