PHARMACOKINETICS OF VALPROIC ACID OBTAINED AFTER ADMINISTRATION OF 3 ORAL FORMULATIONS TO HUMANS

  • 1 January 1984
    • journal article
    • research article
    • Vol. 20  (1) , 46-49
Abstract
The pharmacokinetics and bioavailability of [the anti-epileptic drug] valproic acid (VPA) were compared in 6 healthy volunteers after oral administration of the drug as follows: 1 g standard tablet form, 1 g enteric-coated tablet form and 0.8 g gelatin-capsule form. Following the administration of standard tablets, VPA concentrations reached a peak mean .+-. SD of 105.4 .+-. 9.0 .mu.g/ml at 1 h and declined monoexponentially with a terminal half-life of 14.9 .+-. 2.4 h. Following the administration of the capsule, the serum concentration reached a peak of 82.1 .+-. 14.8 .mu.g/ml at 4 h. Following the administration of an enteric-coated tablet, there was an average time lag of 2 h with a delayed peak serum concentration of 93.5 .+-. 13.1 .mu.g/ml at 6 h. An identical terminal half-life of VPA was obtained for the 3 oral formulations. The bioavailability of the 3 VPA formulations was not significantly different, and it may be concluded that these formulations are bioequivalent.