Are you taking too many medications?

How many medications do you take? Most U.S. adults ages 40 to 79 use at least one prescription drug, and 22% of us take five or more, according to the CDC. The number might be higher if you have several chronic conditions that require treatment. And when you factor in over-the-counter drugs (such aspirin or sleep aids), vitamins, and supplements, your pill burden can grow to double digits.

The more medications in your regimen, however, the greater your risk for problems. To stay safe, learn about the perils of polypharmacy (defined as taking five or more drugs daily) and ways to manage it.

Adverse drug interactions

Taking a lot of medications increases the chance that you might experience a dangerous drug interaction, especially if your doctors aren't communicating with each other about what they're prescribing, or if you use several different pharmacies. There are several types of drug interactions.

Drug metabolism. Sometimes one medication changes how fast the liver breaks down (metabolizes) another drug. The affected drug can then stay in your body too long, becoming too potent, or it can exit quickly, without time to work properly.

For example, the heartburn drug cimetidine (Tagamet) can inhibit certain liver enzymes, slowing the removal of the anticoagulant ("blood thinner") warfarin (Coumadin) from the body. That can increase the warfarin's ability to prevent blood clots, but that might cause bleeding.

In contrast, the herbal remedy St. John's wort stimulates liver enzymes, hurrying warfarin out of the body. That reduces the effect of warfarin and increases blood clot risk.

Similar effects. Sometimes two drugs have the same effect at the same time, causing an extremely powerful result. An example is taking an opioid and a sleeping pill together. "They both depress the central nervous system. The effect becomes amplified, which can cause your breathing to slow too much," says Jigar Mehta, a pharmacist at Harvard­affiliated Beth Israel Deaconess Medical Center.

Blocked absorption. In some cases, one medication can block the absorption of another. For example, calcium carbonate supplements can block the absorption of the thyroid drug levothyroxine (Synthroid).

Other polypharmacy risks

Polypharmacy has additional problems. A large drug regimen is expensive and inconvenient. It can be hard to manage, which increases the chance for errors, such as a missed dose or an overdose. And polypharmacy can be so stressful or confusing that you stop adhering to the program.

Polypharmacy also boosts the odds that you'll experience drug side effects, which are sometimes misinterpreted. "When a medication is causing a side effect such as diarrhea or constipation, that could be missed and considered a symptom of aging. Your team might prescribe an additional medicine to treat the diarrhea or constipation, adding to your burden," Mehta says.

And sometimes certain pills create a high-risk situation when taken together. For example, suppose you take a diuretic for high blood pressure (which can cause frequent urination) and you take tramadol for pain (which can make you feel groggy or dizzy); frequent bathroom trips then can lead to a fall.

What you can do

Taking more than five medications might be necessary for health and symptom control, but it requires extra attention. These strategies can help.

Know what you're taking. Learn each pill's name, appearance, and job. Ask why it's necessary and whether it might cause side effects. Find out what to do if you miss a dose or if side effects develop.

Keep a journal. If you are concerned you may be having medication problems, use a notebook or smartphone to track the day, time, and dose of each drug you take, and the date and time of any unusual symptoms. Bring the journal to your doctor visits, so the doctor will be able to tell if a drug is working or causing side effects.

Use organization tools. A sectioned pillbox, an automatic pill dispenser, or even a phone alarm can help you stick to your medication regimen.

Try to downsize. Mehta recommends scheduling a complete medication review with your doctor or pharmacist at least once a year, and asking if any pills can be omitted. Perhaps there's overlap among drugs, or maybe there's one you've been taking for years, such as a heartburn medication, that was intended only for a short time and is no longer needed.

Don't stop a pill on your own. It can be dangerous to abruptly stop certain medications, such as antidepressants. Work with your doctor to gradually decrease the amount you take. "The act of deprescribing must be just as carefully managed as prescribing," Mehta says.

Dispose of unneeded pills. You don't want old pills around the house, where you or a loved one might take them accidentally. Don't just toss them in the trash or toilet. Many (but not all) pharmacies have drug take-back boxes for proper disposal.

Stay vigilant. The only constant in life is change, and your medication plan will evolve as time goes on. Stay alert to polypharmacy dangers and don't let your guard down.

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