Pharmacokinetics of Valproic Acid After Oral and Intravenous Administration

The kinetics of sodium valproate (di‐n‐propyl‐acetate, Depakine®) have been studied in six healthy volunteers after administration of single oral and intravenous doses (800 mg). Kinetic parameters were similar for both routes of administration. In all subjects absorption was rapid and complete. Half‐lives ranged from 11–15 h. Apparent volumes of distribution were relatively low (0.147 ± 0.0041/kg) and showed little variation amongst individuals. The factors responsible for the poor correlation between dosage and serum levels during chronic treatment and therapeutic implications are discussed.