Weight gain during treatment with valproate.

An analysis was made of weight changes during treatment with valproate in 63 adult epileptic patients. 36 patients (57%) gained more than 4 kg in weight during treatment, while 27 patients (43%) were stable in weight with weight changes of less than +/- 4 kg. There were no significant differences between weight gainers and weight-stable patients with regard to age, sex, pretreatment overweight, duration of treatment, dosage or serum levels of valproate. From structured patient interviews, it appeared that the 2 groups of patients differed only insignificantly with regard to appetite, thirst and familial predispositions to obesity and diabetes. Consequently, no factors predictive for weight gain could be outlined. Presumable pathogenic mechanisms of importance are discussed.