Preventing Drug Interactions in Older Adults

Drug interactions are a serious potential problem older adults face when taking multiple medications. They consume a large share of the nation’s medications, with adults over age 60 buying 30 percent of all prescription drugs and 40 percent of all over-the-counter drugs. The Food and Drug Administration is working to make drugs safer for adults.

“Drug interactions happen when two or more drugs are mixed in the body, interacting with one another and producing side effects which could be dangerous,” said Michael Fetterolf, MD, ThedaCare Physicians-New London.

The average older adult is taking more than four prescription medications at once. Add the over-the-counter medicine they also take and there is a great risk for drug interactions. “Also, as people get older, their bodies change in how they absorb and metabolize medications,” said Ellen Wenberg, MD, ThedaCare Physicians-Waupaca.

They may lose muscle tissue and gain fat tissue, and their digestive system, liver, and kidney functions slow down. All this affects how a drug will be absorbed into the bloodstream, how it will react in the organs, and how quickly it will be eliminated. “When it comes to seeing how an older patient will respond to a new medication, the old adage ‘Start low and go slow’ applies especially to older patients” said Dr. Wenberg.

A doctor will advise when it is OK to take multiple medications. For instance, high blood pressure is often treated with several different drugs. Or many older people have multiple cardiovascular diseases, like high cholesterol, high blood pressure and heart disease, that require multiple drugs for treatment.

“It is important to make your doctor aware of all the medications, both prescription and over the counter, that you are taking before she prescribes additional medications,” said Dr. Wenberg.

Dr. Fetterolf agreed. “If you have several doctors, make sure they all know what the others are prescribing, and ask one doctor, such as a family physician or general internist, to coordinate your drugs.”

Call a doctor when there are symptoms like dizziness, constipation, upset stomach, sleep changes, diarrhea, incontinence, blurred vision, mood changes, a rash or other symptoms occur.

Here are some tips to prevent drug interactions:

  • Keep track of side effects. New symptoms may not be from old age but from the medication you're taking.
  • Learn about your drugs. Find out as much as you can by asking questions and reading the package inserts. Both your doctor and pharmacist should alert you to possible interactions between drugs, how to take any drug properly, and whether there's a less expensive generic drug available.
  • Have your doctor review your drugs. Bring all of your medication bottles, prescription and over the counter, to your doctor visits. 
  • Ask the doctor, "When can I stop taking this drug?" and, "How do we know this drug is still working?"
  • Ask a pharmacist what foods to take with each drug. Some drugs are better absorbed with certain foods, and some drugs shouldn't be taken with certain foods.
  • Follow directions. Read the label every time you take the medication to prevent mistakes and be sure you understand the timing and dosage prescribed.
  • Don't forget to take your medicines. Use a memory aid to help you, like a calendar, pill box, or your own system.