Spotlight on lamotrigine for depression. 
Augmentation strategy is an option for patients who do not respond to one or two adequate trials of antidepressant therapy and are considered treatment-resistant.  A number of drugs have been proposed for this indication, including lamotrigine, an anticonvulsant that is also licensed for the treatment of bipolar I disorder.  Three retrospective chart reviews provided preliminary evidence of efficacy.  However, other studies have been very small open-label studies, with the exception of one randomized, double-blind study.  Although these studies indicate that lamotrigine may be effective as augmentation therapy in treatment-resistant depression, larger controlled studies are required to confirm these initial findings and to provide evidence for its use in this indication.