Introduction:Effective treatment of epilepsy depends on medication compliance across a lifetime. Various studies indicate that drug tolerability is a significant limiting factor in medication maintenance. Available antiepileptic drugs have the potential to induce detrimental effects on cognitive function and therefore compromise patient wellbeing. On the other hand, some agents may serve to enhance cognitive function. Aim: To study the impact of some antiepileptic drugs on intellectual functions of idiopathic epileptic children. Methods: 15 children recently diagnosed with idiopathic epilepsy aged 3-17 years were included. All patients underwent full clinical and neurological examination, electroencephalography, brain CT and intelligence testing. The patients were treated with carbamazepine (CBZ). The Stanford-Binet -Fifth Edition (SB5) was applied before administration of CBZ, six months and 12 months after the start of antiepileptic therapy. Results: Epileptic children receiving CBZ had significantly impaired intellectual functions after 6 months and 12 months of monotherapy. Conclusion: Carbamazepine can adversely affect intellectual development of the children with idiopathic epilepsy