Depression: a new approach to an old syndrome.

Depression is a medical illness related to an interplay of genetic, biochemical and environmental/experiential factors. Careful diagnosis, using contemporary psychiatric criteria, simplifies treatment by the family physician. Awareness of these criteria may lead to improved selection of candidates for drug treatment and early intervention in recurrent illness. The new nosology in psychiatry avoids much confusion and should take some of the guesswork out of psychiatric treatment in the family physician's office.