Central nervous system effect lamotrigine

Irritability and aggressive behavior occur occasionally, and mentally retarded patients are possibly at greater risk (SEDA-22, 88). Rare central nervous system effects include insomnia, psychosis (SEDA-20, 63), downbeat nystagmus (SEDA-22, 89), movement disorders (SEDA-21, 72), and a Tourette-like syndrome. Lamotrigine can increase seizure frequency and severity in children with severe myoclonic epilepsy (SEDA-21, 72). 

Cohen, A. R, Ashby, L., Crowley, D., Land, G., Peck, A. W., Miller, A. A. Lamotrigine (BW430C), a potential anticonvulsant. Effects on the central nervous system in comparison with phenytoin and diazepam. Br. J. Clin. Pharmacol. 1985, 20, 619-629. 

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