Augmentation strategies: focus on anxiolytics.

Approximately 20% to 40% of patients will fail to respond to the first antidepressant used for their current major depressive episode. Furthermore, it has been suggested that a further 20% to 30% of patients will have only a partial response. There are four main options to consider in the treatment of these patients: optimization, substitution, augmentation, and combination therapy. Several combination antidepressant treatments have been used in treatment-refractory depression. Moreover, various augmentation strategies have also proved to be successful. Although the empirical data to support these treatment options are limited, augmentation treatment has several potential advantages over the other clinical options available, particularly substitution. These data are reviewed and clinical applications discussed. Particular attention is paid to the role of anxiolytics as augmentation agents in the treatment of major depression.