Oxcarbazepine (OXC) is a widely used novel antiepileptic drug that has been available for routine prescription for 10 years. To examine low dose OXC-induced neurotoxic effects on cerebellar development, we administered 25 mg/kg OXC orally to newbom Wistar rats once a day on postnatal days 2-14. Microscopic processed cerebellar sections of the control and treated groups were examined by volumetric analysis. Volume estimations were obtained using the Cavalieri's principle using a computerized stereological image analyzer (CAST-GRID). The total volume of the cerebellum, white matter and the various cerebellar layers (except extragranular layer) were significantly increased in the treated animals. These data may provide useful implications for the management of OXC-induced developmental neurotoxicity in children exposed to OXC during the late fetal period. Our finings suggest that women suffering from epilepsy should be given OXC carefully only at the lowest effective doses during pregnancy.