Polypharmacy is defined as the concurrent use of five or more medications. It's extremely common in older adults — up to 40% of those over 65 take five or more daily medicines — and its risks are significant and often underappreciated.
The risks of polypharmacy
- Drug-drug interactions — some combinations are dangerous; warfarin and NSAIDs, for example, greatly increase bleeding risk
- Drug-disease interactions — a medication appropriate for one condition can exacerbate another; diuretics for heart failure can worsen gout
- Adverse drug reactions — the more medications taken, the higher the cumulative risk of side effects, some of which are subtle and attributed to ageing rather than pharmacology
- Falls — many common medications cause postural hypotension, sedation and balance impairment, dramatically raising fall risk
- Cognitive impairment — anticholinergics, benzodiazepines and opioids can impair cognition; in older adults, this may be mistaken for dementia
- Non-adherence — a complex regimen with multiple medications and varying instructions is difficult to follow correctly
The medication review
A structured medication review — ideally with a clinical pharmacist — periodically assesses whether every medication remains necessary, appropriate and safe. The STOPP/START criteria provide a validated framework for identifying potentially inappropriate prescribing in older adults. Patients and carers can request this review; it doesn't have to happen only at a GP's initiative.
Bring every medication — including OTC drugs, supplements and herbal products — to each review appointment. Many interactions involve substances that aren't prescribed.