PHARMACOKINETICS AND BIOAVAILABILITY OF METHYLPHENOBARBITAL IN MAN

  • 1 January 1981
    • journal article
    • research article
    • Vol. 3  (1) , 39-44
Abstract
The pharmacokinetics and bioavailability of mephobarbital were studied in 2 volunteers. Plasma levels of mephobarbital and phenobarbital were measured by gas chromatography-mass spectroscopy with selected ion monitoring. Urinary output of phenobarbital and the p-hydroxy derivatives of both mephobarbital and phenobarbital was measured by high pressure liquid chromatography. The time course of these plasma and urinary levels was monitored following single 800 mg oral and 200 mg i.v. doses in the 2 patients. The major conclusions of the study were that mephobarbital is reasonably well absorbed following oral dosing and that some 35% or so of the dose (by either route) is converted to the recently identified metabolite, p-hydroxymephobarbital.