In vitro, leptin secretion and mRNA levels in adipocytes decrease in response to valproic acid, and it is believed that altered leptin levels might influence weight gain in people taking compounds containing valproic acid [6]. Other researchers have reported that postprandial insulin and proinsulin levels increase in people taking valproic acid, and BMI is positively related to two-hour postprandial levels of insulin, proinsulin, and C-peptide [7]. Luef and colleagues indicate that treatment with valproic acid might increase glucose stimulated pancreatic section, which could be related to higher body weight due to two factors that are related to pancreatic beta-cell regulation and insulin secretion. First, valproic acid is a free-fatty acid (FFA) derivative that competes with FFAs for albumin binding, and, second, valproic acid is a GABA agonist. Thus, valproic acid treatment might increase glucose stimulated pancreatic secretion and contribute to weight gain. Evidence from other laboratories suggests that valproic acid treatment in children increases insulin levels and decreases glucose levels, which might stimulate appetite [8]. Importantly, Demir and Aysun note that carnitine levels did not correlate with weight gain, suggesting that valproic acid induced weight gain is not due to impairments in beta-oxidation of fatty acids. Carnitine is involved in the transfer of fatty acids into the mitochondria for beta-oxidation. Due to the potential role of FFA and valproic acid in influencing pancreatic beta-cell regulation and insulin secretion, FFA will be measured in the present study at baseline (day 0) and day 21, ½ hour before and one hour after the food intake tests at lunch.