Epidemiology of adverse drug events in the nursing home setting.

There is widespread concern about the level of use, particularly the inappropriate use, of drugs among elderly residents of nursing homes. Medication consumption by these individuals is among the highest of any patient population; residents of nursing homes are prescribed an average of 5 to 8 regularly scheduled medications in addition to those drugs prescribed on an as needed ('prn') basis. Ideally, drug therapy should result in beneficial effects and improved quality of life for patients. However, the development of adverse drug events (ADEs) can compromise the expected benefits of pharmacotherapy for the individual nursing-home resident and may represent a public health problem of considerable magnitude.