Antidepressants. A pharmacological update and rationale for treatment.

1. Depression has a prevalence and incidence of significance affecting the morbidity and mortality of the population as a whole and the work force in particular. A variety of risk factors are associated with depression. Certain drugs and conditions may bring on or mimic depression. 2. The symptoms of a major depressive episode, taken as a whole, have certain objective, definable characteristics. Several classes of drugs are used in the treatment of depression. 3. There are a variety of theories regarding the pathophysiology of depression. The various classes of drugs have mechanisms of action which attempt to address aspects of these theories. 4. The ideal antidepressant drug has a number of qualities, some of which are shared by current medications. None of the currently available antidepressants has all of the ideal drug's properties.