Are You at Risk for Drug Interactions?

Summary:  A recent study suggests that some older adults are at risk for potentially dangerous drug interactions.  Make sure your doctor and your pharmacist are aware of all the supplements, prescription and over-the-counter medicines you take, and ask them to check for potential interactions.

In online forums and at meetings, I hear people with memory loss talk about the medicines and supplements they take.  It’s not unusual for them to reel off a list of several prescription drugs and twenty or more supplements.  Could the combination of some of these medicines be dangerous?

Dima Qato, PharmD, MPH

Potential drug interactions are a concern for everyone, not just for people with memory loss.  Late last year, the Journal of the American Medical Association published an article by Dr. Dima Qato and her colleagues at the University of Chicago on the medicines older Americans take.  The researchers catalogued the drug use of over 2200 people across the U.S., ages 57 through 85.

Here’s what they found:

• 81% were taking at least one prescription medicine
• 42% took at least one over-the-counter (nonprescription) medicine
• 49% took at least one dietary supplement.

The data on people taking more than one medicine might be cause for concern:

• 29% were taking five or more prescription medicines
• 46% of those taking prescription medicines were also using over-the-counter drugs
• 52% of those taking prescription medicines were also using dietary supplements.

Overall, 4% of the people surveyed were at risk of major drug interactions, and half of those potential interactions involved blood thinners.  The risk for dangerous interactions was highest among men ages 75 to 85, with one in ten potentially at risk.

Memory loss and potential interactions

What do these findings mean for people with memory loss?  “We did not specifically examine risk among patients with dementia or Alzheimer’s,” says Dr. Qato.  She notes, however, that “according to our study, the risk for potentially dangerous drug-drug interactions increases with age, as does the prevalence of dementia and Alzheimer’s disease.”   Any cognitive limitations can compound the challenges of managing potential interactions, particularly for people taking multiple medicines for multiple health conditions, she says.

Special concerns about supplements and over-the-counter medicines

Our attitudes about supplements and over-the-counter medicines may contribute to the problem.  “Some may assume that just because a drug is available without a prescription, it's safe,” Dr. Qato says.  “Likewise, patients may erroneously assume that their physician or pharmacist is aware of all the medications they take.  Patients need to know that while medications are often beneficial, there can be risks associated with their use, particularly in combination with other drugs.  If they need to self-medicate with an over-the-counter medicine or dietary supplement, they should consult with their physician or pharmacist first, and specifically ask whether it’s okay to use a new product given the medications they’re already taking.”

Dietary supplements may pose special hazards.  “Older adults should realize that there is limited drug safety information available for the many dietary supplements on the market,” Dr. Qato says. “Complete and comprehensive information on the side effect profiles of these supplements as they relate to memory loss is limited as well. Dietary supplements are regulated differently, with less stringent requirements than for prescription and over-the-counter drugs.   Therefore, it is very important that patients with or without dementia consult with their physicians on the benefits and the risks of using these supplements, especially in combination with their prescription and nonprescription medications.”

Practical tips for avoiding drug interactions

On a practical level, what can older adults like those in the University of Chicago study do to lower their risks of dangerous drug interactions?  “The biggest danger that seniors face from their medications and supplements is not knowing why they’re taking them and not knowing whether they are safe to take in combination,” says Dr. Qato.   “Seniors, like all people, need to be active participants in their health care.  They need to ask their physicians and pharmacists why they are taking a certain drug, what the side effects are, and whether it’s safe with the other prescription and products they are using. Carrying a list of all medications in a wallet can be helpful.  Getting their prescriptions filled at one pharmacy or pharmacy chain can help maintain a centralized comprehensive profile of their medications prescribed by multiple physicians and specialists. Pharmacists are easily accessible, and have the most up-to-date drug safety information available to them. They can work with the patient’s physician in developing an optimal treatment strategy.  Finally, among physicians, geriatricians are specially trained to help seniors manage their medications and overall health.”

Comments

[Ajlouny]

This poses a problem for so many people. How can you guarantee that your doctor is well versed in all of the medication that you are taking. High blood pressure, cholesterol, diabetes and hormone pills, there are people that take pills for all those symptoms. How do you get your heart doctor and diabetes doctor and you gynecologist to understand the cocktail that they prescribe?

[hautkrebs]

Thanks for sharing this information.
Late last year, the Journal of the American Medical Association published an article by Dr. Dima Qato and her colleagues at the University of Chicago on the medicines older Americans take.