We report here the involvement of valproic acid in symptomatic hypocalcemia in an 11-year-old epileptic white patient in treatment with valproic acid and lamotrigine. During the treatment the patient developed hypocalcemia associated with high plasma levels of valproic acid, parathyroid hormone and alkaline phosphatase, indicating increased bone turnover. Plasma levels of Vitamin D were normal. Plasma calcium values significantly correlated with valproic acid haematic levels; reduction of valproic acid dose was accompanied by prompt normalization of ...