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This article originally appeared in the March 2008 Harvard Heart Letter and is provided courtesy of Harvard Health Publications.
Troublesome medications
Pay special attention to a quintet of drugs used by people with heart disease.
All medications, from alpha blockers to vitamins, have the potential to cause unwanted side effects. Usually, though, they don’t, and their benefits far outweigh the chances of harm. But for a few medications, benefit and risk are so close together that the drugs are deemed “potentially inappropriate” for older people. A catalog of such drugs, called the Beers list, includes nearly 80 medications.
The handful of heart medicines on the Beers list includes amiodarone, nifedipine, and ticlopidine. Inclusion on the list doesn’t mean a drug should never be used by an older person, just that it should be prescribed — and used — with extra care.
Each year more than 175,000 Americans over age 65 end up in a hospital emergency department because of bad reactions to a prescribed medication. Such adverse reactions range from a rash or itching to bleeding, trouble breathing, an irregular heart rhythm, and more. Only a minority of these visits — under 4% — are related to one of the drugs on the Beers list, according to an interesting analysis from the Centers for Disease Control and Prevention (CDC). Half of such visits are due to appropriate medications. Leading the pack are warfarin, insulin, aspirin, clopidogrel, and digoxin (see table).
The difference can’t be explained by how often the various drugs are prescribed. In the CDC analysis, Beers list drugs were prescribed in 10% of office visits among older people, while warfarin, insulin, and digoxin were prescribed in under 3% of visits.
Necessary but tricky drugs
If warfarin, insulin, digoxin, and the other drugs on the CDC list had equally effective but safer alternatives, the take-home message from this study would be a no-brainer: switch! But these are all necessary and important drugs.
The findings aren’t meant to frighten anyone away from these medications, lead author Dr. Daniel S. Budnitz told us. “But they do provide a wake-up call for doctors who are prescribing these medications and for patients who are taking them.”
We certainly can’t replicate the wealth of information you can — and should — get from your doctor about taking any prescribed medication. Instead, here are some general tips about taking the drugs on the CDC list.
Warfarin
Warfarin, prescribed as Coumadin or generic warfarin, is used to prevent blood clots.
Check your bleeding time (INR) at home, if at all possible, or on the schedule your doctor has set.
Take care if you are also taking a nonsteroidal anti-inflammatory drug, such as ibuprofen, naproxen, or aspirin. When added to warfarin, these increase the chances of gastrointestinal bleeding. Acetaminophen is an alternative, but note that taking it several times a day can increase the bleeding risk of warfarin. Try to keep your intake of green, leafy vegetables and alcohol steady from day to day.
Call your doctor if you experience any of the signs and symptoms of bleeding, including nosebleeds that won’t stop, red blood in the stool, black and tarry stools, bloody vomit, a cut that won’t stop bleeding, or coughing up blood.
Insulin
Insulin is an injectable medication used to control blood sugar. It is prescribed under a variety of names. These include Apidra, Humalog, Humulin, Lantus, Levemir, Novolin, and NovoLog.
Check your blood sugar several times a day. There aren’t any rigid rules on this, but good times include soon after getting out of bed, just before and 90 minutes after meals, if you think you are having low blood sugar symptoms, before bed, and before and after exercising. Check more often if you are sick or whenever you change any of your medications.
Take care to store insulin properly and carry a ready supply of insulin and glucose wherever you go.
Be aware of the signs and symptoms of low blood sugar, including nervousness and shakiness, perspiration, dizziness or light-headedness, fatigue, confusion, difficulty speaking, feeling anxious or weak, and feeling tired, irritable, or confused when you wake up.
Digoxin
Digoxin is usually taken to help an injured or weakened heart pump better. It is prescribed under the names Cardoxin, Digitek, Lanoxicaps, and Lanoxin.
Check your pulse when you are calm and relaxed early in the day. If it is slower than it should be (ask your doctor to specify a safe lower limit), call your doctor or nurse about whether you should take digoxin that day.
Take care if you begin using one or more over-the-counter medications that may interfere with the effects of digoxin, especially antacids; cold, cough, or sinus medicines; and laxatives or medicines for diarrhea.
Call your doctor if you experience changes in vision; drowsiness, headache, confusion, depression, or fatigue; muscle weakness; vomiting, diarrhea, or loss of appetite; or an irregular heartbeat or slow heart rate.
Aspirin and clopidogrel
Aspirin is sold under a variety of names; clopidogrel is available only as Plavix. Both are used to prevent blood clots.
Check that you are taking the dose your doctor prescribed and at the recommended times.
Take care when you are using these medications together or with warfarin. If you are taking clopidogrel after placement of a coronary stent, don’t stop it without talking with your cardiologist.
Call your doctor if you experience any of the bleeding warning signs listed above for warfarin.
Oral medications for diabetes
A number of oral medications are used to keep blood sugar in check. These include metformin (Fortamet, Glucophage, Glumetza, Riomet; also in Actoplus Met, Avandamet, Glucovance, Janumet, Metaglip), glyburide (Diabeta, Glynase, Micronase, Gluconase), and glipizide (Glucotrol, Metaglip).
Check your blood sugar on the schedule your doctor recommends.
Take extra care with these drugs if you have any type of kidney disease or heart disease.
Be aware of the signs of low blood sugar listed for insulin.
Educate yourself
More than four centuries ago, Sir Francis Bacon wrote a now-famous phrase, “Scientia potentia est,” loosely translated as “Knowledge is power.” That’s an excellent aphorism for medications. Knowing as much as possible about the medications you take can help you get the most from them and avoid the worst.
