The epidemiology of polypharmacy

Polypharmacy describes, in simplistic terms, the use of multiple medications in an individual. It has become a normal aspect of modern medicine, driven by an ageing, multimorbid population, the increasing availability of preventative medications and an increasing use of single-disease guidelines and adherence to evidence-based practice. However, polypharmacy is also associated with a range of adverse outcomes, and is considered an important and increasing challenge for clinical practice. Here, we consider the definitions of polypharmacy, the extent and nature of medication use in different settings, and the type of problems encountered as a consequence of polypharmacy.