Treatment-resistant depression: Review of pharmacologic antidepressant strategies

Abstract

Objective: The aim of this study is to review eight pharmacologic antidepressant augmentation strategies in TRD. Methods: Database search on Medline, LILACS and Cochrane Library, from 1990 to June 2006 using the words treatment, resistant, refractory, depression and the medical subject headings depression, drug resistance and augmentation. Double-blind controlled trials and reviews were included. We also consulted reference of the articles in order to obtain studies and original articles of historical value from before 1990. Results: There were 17 double-blind trials with lithium, six with thyroid hormone, two with buspirone, six with pindolol one with carbamazepine, two with lamotrigine and four with olanzapine. Forty-one percent of the trials with lithium, 60% of those with thyroid hormone and tricyclics, 0% of the ones with thyroid hormone and selective serotonin reuptake inhibitors (SSRI), 50% of those with pindolol, 100% of those with carbamazepine and 40% of the ones with olanzapine were favorable. No trials with buspirone were favorable. The only trial with lamotrigine did not show efficacy using the main outcome measures. Otherwise, there was superiority over placebo on secondary measures. Conclusion: Only lithium and thyroid hormone showed efficacy as antidepressant augmentation strategies for TRD. Olanzapine was reasonably studied and did not prove its efficacy. There were just a few studies on buspirone and pindolol and they were not favorable to them. Carbamazepine was studied very little. Lamotrigine was not adequately evaluated.