Polypharmacy, the use of five or more medications simultaneously, though the definition varies, is extremely common in older adults. Nearly 40% of adults aged 65 and older take five or more prescription medications, and when over-the-counter drugs and supplements are included, the number is significantly higher. Each medication added to a regimen increases the potential for drug interactions, adverse effects, and the paradox of medications creating the very problems they were prescribed to prevent.
At Dr. Maryam Khan’s primary care practice in Lutherville-Timonium, MD, systematic medication review for older patients is not an afterthought, it is a clinical priority.
Why Older Adults Are Particularly Vulnerable
Several physiological changes that accompany aging make older adults significantly more susceptible to medication-related problems:
• Reduced kidney function: The kidneys clear most medications from the body. As kidney function declines with age (glomerular filtration rate typically decreases by approximately 1 mL/min/1.73m² per year after age 40), drug levels accumulate more readily, increasing the risk of toxicity at doses that would be safe in younger adults.
• Reduced liver metabolism: The liver’s capacity to metabolize drugs through the cytochrome P450 system also declines with age, affecting how quickly medications are broken down.
• Changes in body composition: As lean muscle mass decreases and fat stores increase with age, the distribution of water-soluble and fat-soluble medications changes. This affects drug concentrations at their site of action.
• Reduced protein binding: Lower serum albumin in older adults (common with malnutrition or chronic illness) means more ‘free’ drug circulating, increasing drug effects and potential toxicity.
• Increased brain sensitivity: The aging brain is more sensitive to the effects of centrally acting medications, sedatives, opioids, anticholinergics, and others, at doses that would not cause significant sedation or confusion in younger adults.
The Clinical Consequences of Polypharmacy
The consequences of polypharmacy in older adults are well-documented and serious:
• Falls and fractures: Sedating medications, blood pressure medications causing orthostatic hypotension, and anticholinergics affecting balance are among the most significant medication-related contributors to falls.
• Cognitive impairment: Multiple medications with anticholinergic properties, some antihistamines, bladder medications, certain antidepressants, and others, have a cumulative ‘anticholinergic burden’ that impairs memory and executive function. This effect can mimic or worsen dementia.
• Hospitalization: Adverse drug events are responsible for approximately 30% of hospital admissions in older adults.
• Adherence problems: The more medications prescribed, the less likely they are all to be taken correctly. Complex regimens with multiple daily dosing times reduce adherence even in motivated patients.
• Prescribing cascade: A prescribing cascade occurs when a side effect of one medication is mistaken for a new medical problem and treated with a second medication, which then causes its own side effects requiring a third, and so on.
| A classic example of a prescribing cascade: a patient begins an NSAID for arthritis pain → develops elevated blood pressure as a side effect → is prescribed an antihypertensive → the antihypertensive causes ankle swelling → a diuretic is added → the diuretic causes incontinence → a bladder medication is prescribed. The patient is now on five medications, four of which trace back to the first NSAID. |
The Beers Criteria: Medications to Approach with Caution in Older Adults
The American Geriatrics Society publishes the Beers Criteria, an evidence-based list of medications that are potentially inappropriate for use in older adults because their risk-benefit ratio is unfavorable in this population. Common examples include:
• Diphenhydramine (Benadryl and many OTC sleep aids): Causes sedation, urinary retention, constipation, and confusion in older adults
• Benzodiazepines (Xanax, Valium, Ativan, Klonopin): Associated with significantly elevated fall and fracture risk and cognitive impairment
• First-generation antihistamines: Strong anticholinergic effects
• Muscle relaxants (cyclobenzaprine, carisoprodol): Poorly tolerated in older adults
• Nitrofurantoin (Macrobid): Contraindicated when kidney function is significantly impaired
Many of these medications are available over the counter and are taken without physician knowledge. This is one reason why a complete medication list, including all OTC medications and supplements, is so important at every visit.
The Medication Review: What Dr. Khan Does
At each visit for her older patients, Dr. Khan conducts an active medication review that goes beyond confirming that prescriptions are being refilled. She evaluates:
• Whether each medication still has an active indication, conditions change, and medications prescribed years ago may no longer be needed
• Whether the dose remains appropriate given current kidney and liver function
• Whether there are drug-drug interactions of clinical significance
• Whether any Beers Criteria medications are present and whether the risk-benefit balance has been re-evaluated recently
• Whether the overall regimen can be simplified by discontinuing medications or substituting formulations that require less frequent dosing
What Patients and Families Can Do
• Keep an up-to-date medication list: Include every prescription, over-the-counter drug, vitamin, supplement, and herbal product. Bring this to every medical appointment.
• Ask at every appointment: ‘Is each of these medications still necessary? Is there anything that can be stopped or simplified?’
• Never stop a medication without talking to a physician: Some medications require gradual tapering rather than abrupt discontinuation. Patients should not stop medications on their own, but they should feel empowered to ask whether it is appropriate.
• Use one pharmacy if possible: A single pharmacy with a complete medication record can catch drug interactions that are missed when prescriptions are filled at multiple locations.
| For a comprehensive medication review as part of your primary care visit in Timonium, MD, contact Dr. Maryam Khan, MD at (443) 577-4010. Located at 1205 York Rd, Suite 11, Lutherville-Timonium, MD 21093. Medicare and commercial insurance accepted. |