Augmentation and combination strategies in resistant depression.

A minority of patients with depression achieves remission with first-line antidepressant treatment; consequently, a second medication is often added to enhance the effects of the initial agent. The second medication may or may not be another antidepressant. Clinical trials have assessed the efficacy of many agents commonly used for augmentation or combination therapy, but well-designed, large trials with a clear definition of treatment resistance are needed. Copyright 2009 Physicians Postgraduate Press, Inc.