Venlafaxine in dysthymic disorder

Dysthymic disorder is a chronic depression that is usually characterized by depression rating scale scores that are lower than those for major depressive disorder. Recent studies suggest that pharmacotherapy is quite effective in the treatment of patients with this condition and, in particular, that the newer antidepressants may be better tolerated than older tricyclic antidepressants. The purpose of this study was to investigate the use of a structurally novel antidepressant, venlafaxine, in the treatment of dysthymic disorder.

Seventeen patients with dysthymic disorder were entered into the study, and 14 completed it. A psychiatric interview was used to establish diagnosis, and behavior was assessed by using the Hamilton Rating Scale for Depression (HAM-D) and the Beck Depression Inventory (BDI). Patients were seen over a 9-week period, and venlafaxine treatment proceeded on an open-label basis, from a starting dose of 18.75 mg b.i.d. to a maximum dose of 225 mg/day.

Two patients discontinued early because of side effects, and 1 patient took a single dose, felt better, and did not complete the trial. Analyses of all 17 patients showed significant improvement in HAM-D and BDI scores at the end of the study. Among the completers, there were two response patterns: one group of 7 patients responded quickly to low-dose (75 mg) venlafaxine, and a second group of 7 required the maximum dose. Three of the 7 high-dose patients showed considerable improvement. Side effects in this study were generally in keeping with what has been reported using venlafaxine in treatment of major depressive disorder. No patients evidenced increased blood pressure.

Our study supports the treatment of dysthymic patients with venlafaxine, which has equal efficacy and greater tolerability than tricyclic antidepressants.