Serum leptin changes in epileptic patients who gain weight after therapy with valproic acid

Weight gain has been recognized as an adverse effect of valproic acid therapy, but there are are no data about serum leptin levels in patients receiving this drug. To evaluate if valproic acid treatment in epileptic patients in whom obesity develops modifies serum levels of insulin and leptin, 40 female patients with epilepsy were evaluated before therapy and after 1 year of therapy. At the end of follow-up, 15 patients were obese and showed higher serum leptin and insulin levels than patients who did not gain weight. As in other types of obesity, elevation of serum leptin concentrations is related to the increase in body mass index.