Changes in Pharmacokinetics and Pharmacodynamics in the Elderly Patient

Abstract

The use of pharmacologic agents in elderly patients is one of the most difficult aspects of patient care. An understanding of the common physiologic changes expected with aging is helpful to anticipate changes expected in pharmacokinetic parameters. Distribution, metabolism, and excretion are significantly altered for many drugs. In addition, pharmacodynamic variations in elderly patients may increase or decrease sensitivity to a medication independent of pharmacokinetic changes. These alterations are particularly noteworthy with cardiovascular and central nervous system agents. Current controversies regarding the application of estimation of renal function to drug dosing and use of the Beers criteria of medications potentially inappropriate in the elderly are discussed.