Prescribing for older patients: how to avoid toxic drug reactions.

As a group, persons age 65 and older are the largest consumers of pharmaceuticals, accounting for 30% of prescription drugs and 40% of over-the-counter medications. Many elderly patients take multiple medications for a variety of concurrent medical conditions. The use of two or more drugs, combined with widely varying degrees of disease-related and physiologic impairment of function, can lead to unintended adverse reactions and even death. The physician can help to minimize adverse drug reactions and improve outcomes by being aware of the principles of clinical pharmacology, the characteristics of specific drugs, and the special physical, psychological, and social needs of older patients.