zonisamide efficacy as adjunctive therapy in children with refractory epilepsy

how to cite this article: karimzadeh p, ashrafi mr, bakhshandeh bali mk, nasehi mm, taheri otaghsara sm, taghdiri mm, ghofrani m. zonisamide efficacy as adjunctive therapy in children with refractory epilepsy. iran j child neurol. 2013 spring; 7(2):37-42. objective approximately one third of epileptic children do not achieve complete seizure improvement. zonisamide is a new antiepileptic drug which is effective as adjunctive therapy in treatment of intractable partial seizures. the purpose of the current study was to evaluate the effectiveness, safety, and tolerability of zonisamide in epileptic children. materials & methods from november 2011 until october 2012, 68 children who referred to children’s medical center and mofid children hospital due to refractory epilepsy (failure of seizure control with the use of two or more anticonvulsant drugs) entered the study. the patients were treated with zonisamide by dose of 2- 12 mg/kg daily in addition to the previous medication. we followed the children every three to four-weeks intervals based on daily frequency, severity and duration of seizures. during the follow-up equal and more than fifty percent reduction in seizure frequency or severity known as response to the drug. results in this study 68 patients were examined that 61 children reached the last stage.35 (57.4%) were male and 26 (42.6%) patients were female. after first and six months of zonisamide administration daily seizure frequency decreased to 2.95±3.54 and 3.73±3.5 respectively. there was significant difference between seizure frequency in first and six month after zonisamide toward initial attacks. after six months zns therapy a little side effects were created in 10 patients (16.4%) including stuttering(4.9%), decreased appetite (4.9%), hallucination (1.6%), dizziness(1.6%), blurred vision(1.6%) and suspiring(1.6%) as all of them eliminated later dosage reduction. conclusion this study confirms the short term efficacy and safety of zonisamide in children with refractory epilepsies.   references 1. michal v. johnston. seizure in childhood. in: robert m. kliegman, richad e. behrman. nelson text book of pediatrics.18th edition; 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