Psychotropics and drug interactions in the elderly patient.

This short paper attempts to provide a framework to aid the old-age psychiatrist in choosing psychotropic drugs in a way that minimizes the risks of adverse drug reactions. It concentrates on the clinical problems most frequently encountered in old-age psychiatric practice. Older people are at risk of adverse drug interactions because of their higher rate of physical morbidity and increased likelihood of receiving polypharmacy, as well as due to age-related change in drug handling. The strongest evidence for relevant interactions in older people relates to changes in renal excretion (particularly relevant for lithium) and cytochrome P450 (relevant for a wide range of psychotropic and other drugs). Awareness of potential interactions is important in ensuring safe prescribing practice for older people with mental health problems. Copyright 2001 John Wiley & Sons, Ltd.