LACK OF KINETIC INTERACTION BETWEEN VALPROIC ACID AND CITRUS PECTIN

To determine the influence of ingestion of dietary fiber (citrus pecti n) in the kinetic disposition of valproic acid, two studies were condu cted in adult volunteers. Twelve healthy subjects took single oral dos es of 500 mg valproic acid in a form of sodium valproate as coated tab lets, on two occasions: under fasting conditions (treatment A) or imme diately after ingestion of 14 g citrus pectin (treatment B). In each s tudy, a randomized, single-dose, two-way crossover design was used, an d 8 days elapsed between the two trials. Assays were carried out for v alproic acid in plasma samples, which were collected from zero to 48 h ours after drug administration. The peak plasma concentration (60.52 v s. 55.74 mu g x ml(-1)), the time to peak concentration (3.47 vs. 3.91 h), the absorption rate constant (0.12 vs. 0.12 h(-1)), and the area under the plasma concentration-time curve (1324.0 vs. 1268.5 mu g x h x ml(-1)) did not differ significantly between treatments A and B (med ian, Wilcoxon test). These results suggest that the administration of citrus pectin does not alter the rate and extent of absorption of valp roic acid administered as a single dose to healthy volunteers.