Excretion of D-glucaric acid and metabolism of salicylamide in man: the effect of phenobarbital-produced enzymatic induction.

In 16 young healthy subjects the composition of salicylamide metabolites and the rate of their excretion depended on the loading dose. After 5 days of treatment with phenobarbital, the excretion of glucaric acid (GLA) and the rate of excretion and degree of glucuronization of salicylamide metabolites increased over 2-fold. The rate of excretion and degree of glucuronization were correlated with the amount of excreted GLA. The value of assay of GLA for the assessment of induction of hepatocytic microsomal enzymes is discussed.