[D-xylose absorption test. A pharmacokinetic and statistical study].

D-xylose pharmacokinetics has been studied in 6 healthy subjects by serial measurement of blood and urinary levels following oral and intravenous administration of two doses of D-xylose (5 and 25 g successively). Furthermore, patients with obesity, renal or hepatic insufficiency, or with a T-drain after cholecystectomy, are also investigated. Both the rate and completeness of D-xylose absorption and the apparent distribution volume of D-xylose present noteworthy interindividual variations, so that the time and value of the peak blood level are highly variable as between healthy subjects. Renal insufficiency increases the apparent elimination half-life of D-xylose and notably reduces D-xylose renal excretion. This study provides pharmacokinetic evidence of the very wide range of blood and urinary levels observed in the D-xylose tolerance test, and emphasizes the fact that D-xylose urinary excretion alone is not a reliable index of intestinal absorption.