Personal Health Navigator

How to reduce the risk of side effects in seniors taking multiple medications

Elderly holding medication bottles
Written by Paul Taylor

QUESTION: My mother is in her 70s and suffers from a lot of health problems. I am very worried that she has been given too many different medications that are too strong for her. What should I do?

ANSWER:  It’s possible that your mother may need all the drugs she is currently taking. But it’s also true that patients sometimes get prescribed drugs and remain on them when they are no longer required.

“Doctors are really good at starting medications, we are not so good at stopping them,” says Dr. Kimberly Wintemute, the primary care co-lead of Choosing Wisely Canada, an organization dedicated to reducing unnecessary medical treatments.

During a hospital stay, for instance, a patient might be given a sleeping pill or a heartburn drug and the prescription keeps getting renewed.

Over time, a patient can end up on a growing list of medications.  About two-thirds of seniors living in their own homes take five or more drugs, according to data collected by the Canadian Institute for Health Information. One-quarter of seniors are prescribed 10 or more medications.

Each new drug that’s added to the mix increases the risk of adverse side effects and medication interactions.

The elderly are especially vulnerable to these problems.  Not only do they tend to have more chronic conditions than younger people, but the aging process can also change the way the body handles medications.

For instance, the liver and kidneys – which play a key role in processing and excreting drugs – tend to work less efficiently as we age.

In fact, the liver can sometimes become overwhelmed trying to handle several drugs simultaneously. As a result, certain medications don’t get “activated” and essentially won’t work.

“Picture a bus and everyone is trying to get on at the same time – some people are not going to fit and will be left behind,” explains Dr. Cara Tannenbaum, co-director of the Canadian Deprescribing Network, a group that is trying to prevent the inappropriate use of medications.

“Conversely, if the liver is overloaded with multiple medications, certain medications may get deactivated more slowly, leading to rising blood levels, side effects, and potential toxicity.”

Furthermore, as we age, we tend to lose muscle mass which is replaced with fat and that can cause problems because some drugs are stored in fat tissue. That means medications can linger longer in the body and thereby exaggerate their effects, says Dr. Wintemute, who is also a family doctor at North York General Hospital.

What was once an appropriate dose of a medication at the age of 60 may be too high by the age of 70.

Another concern is the government approval process for new medications. Drugs are usually tested on relatively young people with just one medical condition – not elderly individuals with multiple ailments. “We don’t always know how a new drug is going to act in very old and very frail people,” says Dr. Debbie Elman, the lead physician for the Academic Family Health Team at Sunnybrook Health Sciences Centre.

Patients may suffer from a host of side effects and drug interactions including confusion, dizziness, fatigue, constipation, diarrhea, incontinence, weight loss, depression, agitation, anxiety as well as sexual dysfunction.

“Sometimes we end up prescribing a medication to combat the side effects of another medication, which is truly unfortunate,” says Dr. Elman.

It can also be difficult to tell if a particular symptom is caused by a medication or it represents a new medical ailment.  A patient might be wrongly diagnosed with dementia or another condition even though a drug is really to blame.

So, what can be done to reduce the risks posed by multiple medications?

First and foremost, a patient should get all medications at the same pharmacy, advises Dr. Elman.

She points out that patients are often treated by several medical specialists – and each one may be prescribing different medications. No single doctor may have a complete picture of what a patient is taking. However, when all prescriptions are picked up at the same drug store, the pharmacist can check for potentially hazardous drug combinations.

The pharmacist can also conduct a review of a patient’s medications and help determine if some may no longer be appropriate.

For a thorough assessment, the pharmacist will need to know if the patient is also taking any non-prescription drugs, herbal remedies or vitamin and mineral supplements. It’s important to keep in mind that so-called “natural” health products can interact with medications and either reduce or intensify their effects. A calcium supplement, for example, can bind to a thyroid medication in the gut so that neither one enters the bloodstream.

Many patients don’t know why they are taking certain medications or what they do, says Dr. Tannenbaum, who also holds the Michel Saucier chair in Geriatric Pharmacology, Health and Aging at the University of Montreal.

She suggests that patients, or their family members, should use the website to learn more about their medications. Simply type in the name of a drug and up pops a lot of useful information, including if a certain medication might be particularly risky for seniors. Another website,, provides guidance on how to wean off a medication that may be harmful or is no longer needed.

Of course, patients shouldn’t quit taking a drug without consulting their medical specialists or family doctor.  But by first talking to a pharmacist, and checking out the recommended websites, they can at least have an informed discussion with the physician responsible for their medical care, says Dr. Tannenbaum.

Dr. Wintemute has one last piece of advice: Patients should bring along all their pills and supplements to that doctor appointment so nothing is overlooked.

About the author


Paul Taylor

Paul Taylor retired from his role as Sunnybrook's Patient Navigation Advisor in 2020. From 2013 to 2020, he wrote a regular column in which he provided advice and answered questions from patients and their families. Follow Paul on Twitter @epaultaylor