Normal disposition of oxazepam in acute viral hepatitis and cirrhosis

Abstract

Oxazepam (Serax) is a tranquilizer-sedative of the benzodiazepine group that is predominantly metabolized to a pharmacologically inactive glucuronide and subsequently excreted by way of the kidneys. We administered this drug as a single oral dose to seven patients with acute viral hepatitis, to six with cirrhosis, and to age-matched control subjects. Elimination half-life (T1/2) and the apparent oral plasma clearance for the drug in patients with hepatitis and cirrhosis were comparable to values obtained in age-matched controls (P greater than 0.05). In addition, the apparent volume of distribution of oxazepam, its plasma binding, blood/plasma ratio, and the rate of urinary excretion of oxazepam, predominantly as the glucuronide, were comparable (p greater than 0.05) in the two groups of patients with liver disease and their respective controls. Unlike many other sedatives, oxazepam is eliminated normally in patients with parenchymal liver disease an therefore, on pharmacokinetic grounds, seems to be an excellent sedative for use in such persons.