Trazodone, a new avenue in the treatment of depression

Pharmacological and biochemical data on trazodone are reviewed in order to compare this drug to imipramine and other tricyclics both from the point of view of the mechanism of action and preferential clinical indications. Trazodone tends to inhibit biochemical and pharmacological functions depending on the catecholaminergic system, whereas imipramine has a potentiating activity. However, both these drugs decrease the density of beta-receptors following repeated administrations. Trazodone and imipramine have similar effects on the serotoninergic system. The two drugs also share an antinociceptive activity. It is stressed that this activity has been of critical importance in the discovery of trazodone. In fact, the development of this drug was based on the working hypothesis that a disturbance in the perception of unpleasant experience has a role in the pathogenesis of depression. Some medical implications of the alpha-blocking activity of trazodone are discussed. Trazodone is preferable to other antidepressant treatment when depression is associated with angle-closure glucoma, cardiovascular disturbances depending on noradrenaline release, tremor, some psychotic conditions and alcoholism.