Metabolic studies of 5‐fluorouracil—II. Influences of the route of administration on the dynamics of distribution in man

Abstract

Portal and peripheral plasma and bile levels of 5‐fluorouracil were determined after oral and intravenous administration of the 2‐ 14C labelled isotope in man. Initial peak levels of radioactivity resulting from intravenous administration were followed by a rapid disappearance of the isotope. Ingested drug appeared in the portal plasma in less than 5 minutes and resulted in sustained higher concentrations in the plasma and bile 30 to 60 minutes later. Significant 5‐fluorouracil is excreted into the gut via the biliary tree. Sustained portal concentrations of active drug suggest that continued absorption from the small intestine occurs. Copyright © 1974 American Cancer Society