Medication Management and Polypharmacy
Core concepts
Polypharmacy is commonly defined as five or more medications, and it matters because of cumulative risk: adverse drug events, interactions, and prescribing cascades. Know the prescribing cascade-treating a drug side effect with another drug-and the concept of deprescribing using tools like the Beers criteria and STOPP/START. Recognize high-risk drug classes in older adults: benzodiazepines, anticholinergics, sedative-hypnotics, long-acting sulfonylureas, and NSAIDs. Understand altered pharmacokinetics/pharmacodynamics with aging: reduced renal clearance, altered volume of distribution, and increased sensitivity to sedatives and anticholinergics. Anticholinergic burden contributes to confusion, constipation, urinary retention, and falls. Always reconcile medications at transitions.
Traps
Questions reward identifying the culprit drug and stopping it rather than adding another. A frequent trap is choosing a new medication to manage a symptom that is actually a drug side effect. Another is ignoring renal dosing. Watch for distractors that continue a Beers-listed drug because it "worked before."
Rule of thumb
Before adding any drug, ask: Could an existing medication be causing this? If yes, deprescribe first.
Worked example
An older adult on oxybutynin develops new confusion and constipation. The best action is to recognize anticholinergic burden and stop or switch the drug, not to add a laxative and a cognition aid-removing the cause resolves multiple symptoms.