n. an anticonvulsant drug used as an adjunct in the treatment of adults with partial seizures and some generalized seizures and for maintenance treatment of bipolar disorder. Although ineffective in treating acute manic episodes, it has gained acceptance as a single-drug treatment for acute bipolar depression and rapid-cycling bipolar II disorder. Serious skin reactions, including Stevens–Johnson syndrome, have been reported at the start of therapy, particularly in children. U.S. trade name: Lamictal.