No effect of long-term valproate therapy on thyroid and parathyroid functions in children

In this study, we studied serum calcium, phosphorus, alkaline phosphatase, thyroid hormones (total thyroxine, free thyroxine, thyroid-stimulating hormone), parathyroid hormone, and osteocalcine levels in children with epilepsy who had been receiving long-term valproate (VPA) therapy in order to determine whether there was any effect of VPA therapy on these hormones. The study included 31 patients with epilepsy receiving VPA and 22 healthy age-matched controls. The age ranged from 15 months to 16 years and 18 months to 17 years in the study and control group, respectively. The duration of VPA use was between 12 months and 5 years (1.93 +/- 1.90 years). When comparing the results, we did not find any significant difference in any of the parameters, including serum calcium, phosphorus, alkaline phosphatase, osteocalcine, and thyroid and parathyroid hormone levels, between the study and control group. We suggest that VPA can safely be used with regard to thyroid and parathyroid dysfunction in childhood epilepsy.