Citalopram and bupropion-SR: combining versus switching in patients with treatment-resistant depression

There are limited data comparing medication strategies in patients with treatment-resistant depression. In this study, we compared the effects of combining citalopram and bupropion-SR versus switching to the other monotherapy in treatment-resistant depression.

This was a naturalistic, open-label cohort study. Patients with DSM-IV major depressive disorder who had not responded to at least 1 previous antidepressant and at least 6 weeks of treatment with citalopram or bupropion-SR were treated in a standard clinical protocol. In alternate months, eligible consecutive patients were treated by adding citalopram or bupropion-SR, or by switching to the other medication. Patients were assessed at baseline and after 6 weeks of treatment with the 29-item version of the Structured Interview Guide for the Hamilton Depression Rating Scale, Seasonal Affective Disorders Version (SIGH-SAD).

A total of 61 patients completed the study: 32 in the combination condition and 29 in the monotherapy switch condition. The combination condition was superior to the monotherapy switch in the SIGH-SAD change score (-14.8 vs. -10.1, respectively, p <.04) and the proportion of patients in clinical remission (28% vs. 7%, p <.05). There were no differences in the proportion of patients who had side effects or in the severity of the side effects experienced.

The results of this cohort study suggest that combining citalopram and bupropion-SR is more effective than switching to a monotherapy. Combination treatment was well tolerated with no greater side effect burden than monotherapy. Limitations of this study include the nonrandomized design, open-label treatment, and small sample size.