Understanding and preventing drug interactions in elderly patients.

The elderly consume a disproportionate amount of prescription and nonprescription medications. Alterations in physiology, polypharmacy, multiple prescribers, and other factors place the elderly population at risk of developing clinically significant drug-drug interactions. The incidence of potential drug-drug interactions increases with increased drug use and are responsible for numerous emergency room and physician visits. Drug interactions have been shown to cause a decline in functional abilities in older people. Drugs can interact to alter the absorption, distribution, metabolism, or excretion of a drug or interact in a synergistic or antagonist fashion altering their pharmacodynamics. Drug interactions are often clinically unrecognized and responsible for increased morbidity in elderly patients. Prudent use of medications and vigilant drug monitoring are essential to avoid drug-drug interactions.