Appropriate Polypharmacy and Medicine Safety: When Many is not Too Many.

The use of multiple medicines (polypharmacy) is increasingly common in middle-aged and older populations. Ensuring the correct balance between the prescribing of 'many' drugs and 'too many' drugs is a significant challenge. Clinicians are tasked with ensuring that patients receive the most appropriate combinations of medications based on the best available evidence, and that medication use is optimised according to patients' clinical needs (appropriate polypharmacy). Historically, polypharmacy has been viewed negatively because of the associated medication safety risks, such as drug interactions and adverse drug events. More recently, polypharmacy has been identified as a risk factor for under-prescribing, such that patients do not receive necessary medications and this can also pose risks to patients' safety and well-being. The negative connotations that have long been associated with the term polypharmacy could potentially be acting as a driving factor for under-prescribing, whereby clinicians are reluctant to prescribe necessary medicines for patients who are already receiving 'many' medicines. It is now recognised that the prescribing of 'many' medicines can be entirely appropriate in patients with several chronic conditions and that the risks of adverse drug events that have been associated with polypharmacy may be greatly reduced when patients' clinical context is taken into consideration. In this article, we outline the current perspectives on polypharmacy and make the case for adopting the term 'appropriate polypharmacy' in differentiating between the prescribing of 'many' drugs and 'too many' drugs. We also outline the inherent challenges in doing so and provide recommendations for future clinical practice and research.