Psychoactive drugs and the frail elderly patient.

Rational use of psychoactive drugs in frail elderly patients requires an understanding of the physiologic changes produced by aging and chronic disease. Other drugs being used and the patient's nutritional status and lifestyle also must be considered. Affective disorders and thought disorders may be effectively treated with much lower doses of appropriate psychoactive drugs than those commonly prescribed. Benzodiazepines are poorly tolerated by old persons because of paradoxic responses and frequent adverse reactions.