A placebo-controlled, cross-over trial of lamotrigine in depersonalization disorder.

There is evidence to support the view that glutamate hyperactivity might be relevant to the neurobiology of depersonalization. We tested the efficacy of lamotrigine, which reduces glutamate release, as a treatment for patients with depersonalization disorder. A double-blind, placebo-controlled, cross-over design was used to evaluate 12 weeks of treatment of lamotrigine. Subjects comprised nine patients with DSM-IV depersonalization disorder. Changes on the Cambridge Depersonalization Scale and the Present State Examination depersonalization/derealization items were compared across the two cross-over periods. Lamotrigine was not significantly superior to placebo. None of the nine patients was deemed a responder to the lamotrigine arm of the cross-over. Lamotrigine does not seem to be useful as a sole medication in the treatment of depersonalization disorder.