Rett syndrome (RS) is a particular neurodevelopmental disorder in which symptoms develop in early infancy and manifests particular symptoms at certain ages. Two girls aged 4.5 and 2.5-years-old were admitted with complaints of seizures, regression of language, psychomotor development, and autistic behavior. They had fulfilled the criteria of classic RS. Lamotrigine was used in the treatment of the convulsions. After lamotrigine therapy, the convulsions were successfully controlled and the stereotyped hand movements and autistic behaviors markedly decreased. We would like to stress that, aside from convulsion, abnormal signs of the syndrome such as stereotyped hand movements and autistic behaviors might also be improved with lamotrigine, but detailed and controlled studies should be performed to identify whether lamotrigine has any positive effects in RS. (C) 2001 Elsevier Science B.V. All rights reserved.