Lamotrigine as an add-on treatment for depersonalization disorder: A retrospective study of 32 cases

Objectives: Depersonalization disorder (DPD) is a chronic condition characterized by the persistent subjective experience of unreality and detachment from the self. To date, there is no known treatment. Lamotrigine as sole agent was not found to be effective in a previous small double-blind, randomized crossover trial. However, evidence from open trials suggests that it may be beneficial as an add-on medication with antidepressants. Methods: We report here an extended series of 32 patients with DPD in whom lamotrigine was prescribed as an augmenting medication. Most of the patients were receiving selective serotonin reuptake inhibitors. Results: Fifty-six percent (n = 18) of patients had a more than or equal to 30% reduction on the Cambridge Depersonalization Scale score at follow-up. Both maximum dose of lamotrigine used and before treatment Cambridge Depersonalization Scale scores showed positive correlations with the percentage of response. Conclusions: The results of this trial suggest that a significant number of patients with DPD may respond to lamotrigine when combined with antidepressant medication. The results are sufficiently positive to prompt a larger controlled evaluation of lamotrigine as "add-on' treatment in DPD.