polypharmacy

thumb|Polypharmacy is often defined as taking 5 or more medicines. Polypharmacy (polypragmasia) is an umbrella term to describe the simultaneous use of multiple medicines by a patient for their conditions. The term polypharmacy is often defined as regularly taking five or more medicines but there is no standard definition and the term has also been used in the context of when a person is prescribed 2 or more medications at the same time. Polypharmacy may be the consequence of having multiple long-term conditions, also known as multimorbidity and is more common in the elderly. In some cases, an excessive number of medications at the same time is worrisome, especially for people who are older with many chronic health conditions, because this increases the risk of an adverse event in that population. In many cases, polypharmacy cannot be avoided, but 'appropriate polypharmacy' practices are encouraged to decrease the risk of adverse effects. Appropriate polypharmacy is defined as the practice of prescribing for a person who has multiple conditions or complex health needs by ensuring that medications prescribed are optimized and follow 'best evidence' practices.

The prevalence of polypharmacy is estimated to be between 10% and 90% depending on the definition used, the age group studied, and the geographic location. Polypharmacy continues to grow in importance because of aging populations. Many countries are experiencing a fast growth of the older population, 65 years and older. This growth is a result of the baby-boomer generation getting older and an increased life expectancy as a result of ongoing improvement in health care services worldwide. About 21% of adults with intellectual disability are also exposed to polypharmacy. The level of polypharmacy has been increasing in the past decades. Research in the USA shows that the percentage of patients greater than 65 years-old using more than 5 medications increased from 24% to 39% between 1999 and 2012. Similarly, research in the UK found that the number of older people taking 5 plus medication had quadrupled from 12% to nearly 50% between 1994 and 2011.