Different kinds of depression have different responsivities to different treatments, though. Melancholic depression, characterized by pervasive anhendonia, nonreactivity of mood, diurnal variation, early morning awakening, guilt, and psychomotor change, has been shown to be more likely to react to tricyclic antidepressants than other forms of depression.

Tricyclics are also effective at treating Obsessive-Compulsive Disorder, which has been linked to low serotonin functioning. The tertiary amine tricyclics, therefore, are most useful at the treatment of OCD. For children who experience enuresis, low doses of Imipramine before bedtime can reduce the likelihood of bedwetting.