BackgroundEpilepsy is a common and devastating neurological disease. Its treatment, especially when using phenobarbital, causes liver complications, and it is therefore essential to identify a way to reduce liver complications. This study aimed to investigate the protective effect of ursodeoxycholic acid on liver function in pediatric patients with seizure treated with phenobarbital. Materials and methods:Materials and methods: The present study was conducted on 80 patients (40 in the placebo group and 40 in the ursodeoxycholic acid group). To assess the effect of intervention, liver enzyme levels after five weeks of treatment were recorded. Independent t-test and ANOVA repeated measures were used to compare the means. Conclusions:The study results showed that the administration of ursodeoxycholic acid had a relative effect in improving liver function in patients with liver injury caused by phenobarbital.