Principles of antidepressant use.

Depression is a disabling illness which tends to be undiagnosed and undertreated. Antidepressants are a specific treatment for this condition, but their effective use requires considerable judgment, knowledge and skill. Many drugs are available, although with a few exceptions there are no substantial differences in their overall efficacy in equivalent doses. Shades of clinical judgment dictate the use of one preparation over the other. In any case, physicians should become thoroughly familiar with several of these agents. A fair trial of treatment requires therapeutic doses for at least three to four weeks. These drugs have a low safety margin and elderly patients are especially at risk for the cardiac, anticholinergic and CNS side effects. Duration of treatment is decided empirically. The successful chemotherapy of depression is one of the most gratifying experiences in medicine.