Polypharmacy

Polypharmacy is the use of four or more medications by a patient, generally adults aged over 65 years. Polypharmacy is most common in the elderly, affecting about 40% of older adults living in their own homes. About 21% of adults with intellectual disability are also exposed to polypharmacy.

Concerns about polypharmacy include increased adverse drug reactions, drug interactions, prescribing cascade and higher costs. Polypharmacy is often associated with a decreased quality of life, decreased mobility and cognition.

It is well accepted in pharmacology that it is impossible to accurately predict the side effects or clinical effects of a combination of drugs without studying that particular combination of drugs in test subjects. Knowledge of the pharmacologic profiles of the individual drugs in question does not assure accurate prediction of the side effects of combinations of those drugs.

Whether or not the advantages of polypharmacy (over monotherapy) outweigh the disadvantages or risks depends upon the particular combination and diagnosis involved in any given case. The use of multiple drugs, even in fairly straightforward illnesses, is not an indicator of poor treatment. A perfectly legitimate treatment regimen could include, for example, the following: a statin, an ACE inhibitor, a beta-blocker, aspirin, paracetamol and an antidepressant in the first year after a myocardial infarction.