5 Things to Know About Taking 5 or More Medications

Drug interactions can cause dangerous side effects

The number of potentially dangerous drug-drug interactions is impossible to estimate, because the potential polypharmacy combinations are practically limitless. One example of a combination to avoid is blood thinners, such as warfarin, and nonsteroidal anti-inflammatory drugs (NSAIDs), including ibuprofen (Advil) or naproxen (Aleve). Taking these two together can increase bleeding risks.

For older adults, cognitive problems like memory issues, disorientation, confusion and clouded thinking are a top concern of taking multiple medications, Schneider says. So are falls. And research shows that the more medications a person takes, the greater the risk for falling.

"A hip fracture in someone in their 70s or 80s is really quite serious and has major implications and effects on mortality,” Schneider says. In fact, falls double the risk of death for an elderly person in the first year after the break, one study shows; the risk remains close to double for several years later.

Polypharmacy can affect brain health

While your daily drug regimen may be designed to improve your joint health or mental health, it could negatively affect your brain health.

For starters, several studies have linked polypharmacy to dementia. What's more, commonly prescribed drugs — from antidepressants to corticosteroids — can cause cognitive problems that mimic dementia. However, unlike dementia, these symptoms are often curable, which is why Keller always considers medications when a person is concerned about their brain health.

"When someone comes in with suspected cognitive decline, the first thing we do is try to find a reversible cause,” he says.

Some classes of medications also have been associated with increased risk for dementia, like benzodiazepines, prescribed to treat conditions from anxiety to insomnia, and anticholinergics, which are used to treat a range of conditions including chronic obstructive pulmonary disease and gastrointestinal disorders. The over-the-counter allergy medicine diphenhydramine (Benadryl) also has anticholinergic effects.

A 2019 study published in JAMA Internal Medicine found that longer-term use of anticholinergics was associated with about a 50 percent higher dementia risk, compared to short-term use.

It's not completely clear how the drugs might increase dementia risk, but a 2016 study found that the brains of those on long-term anticholinergics had atrophied and the hollow spaces inside increased. The neurons also had reduced ability to metabolize glucose. The higher the drug exposure, the more pronounced the effect.

Anticholinergics can also counteract the medications given to improve memory and thought in Alzheimer's disease, making a bad situation even worse. Three common Alzheimer's drugs (brand names Aricept, Exelon and Razadyne) belong to a class called cholinesterase inhibitors. They work by increasing acetylcholine, a chemical that allows the body's nerve cells to communicate with each other, by preventing its breakdown.

Anticholinergics do the opposite. They block the ability of acetylcholine to exert its effect, lowering nerve signaling, thereby decreasing whatever activity those nerves control.

Other hidden dangers lurk in common medicines

Cognitive changes aren't the only potential side effects of these medications, said Shanna Trenaman, a pharmacist at Dalhousie University in Halifax, Nova Scotia, who specializes in geriatrics. Plenty of studies have found that anticholinergics can increase stomach upset and cause constipation and urinary retention.

Some sleep aids (including a number that are sold over the counter) also have anticholinergic effects; these have been linked to increased risk of car wrecks, falls and other injuries, Trenaman says. And medication interactions are possible with these, as well.

"I would encourage everyone to think critically about whether or not they need to take medication for sleep,” Trenaman told AARP. “They help you fall asleep only about seven minutes faster on average, so is that worth these risks?”

If you are taking something to help you sleep and decide to discontinue it, do it with guidance from a health care professional who can help you taper off the medication slowly.

A health care provider should review your medications often

Experts interviewed for this article have a unanimous recommendation: Be proactive in your medication decisions.

Older adults managing multiple health conditions may see several doctors — and each may be unaware of what the others have prescribed. Recently there's been greater attention focused on the concept of deprescribing — or “evaluating people's medications, consciously assessing whether it's really needed, and planning how best to reduce and discontinue it,” Schneider says. It's important to note, however, that patients should never stop taking a drug without consulting a doctor, as this can be dangerous.

Instead, the three experts recommend at least an annual review of medications with your main physician. Bring all of your medications in — don't forget about any over-the-counter medicines you are taking, plus vitamins and supplements — and talk about potential interactions and which drugs you may no longer need.

"There's a perception that all over-the-counter medications are as safe as water, but that's just not true. Antihistamines, anticholinergics and sleep aids are just as potent over the counter as they are by prescription, and they are big contributors to this issue,” Schneider says.

Your pharmacist can also help answer any medication questions, especially when it comes to spotting potentially troublesome drug combinations.