Abstract
A potent anti-cancer agent, 5-flurouracil has been generally given through parenteral routes. In the clinical practice of cancer chemotherapy, many cases are actually considered to be suitable as candidates of oral administration of this particular drug. To solve this practical problem, we studied on the absorption and the organ distribution of this agent, using S-D rats, comparing the two administration methods, namely oral and intravenous administration. Also, pharmacokinetic studies were performed on two patients with advanced breast cancer, to evaluate the above-mentioned two administration routes.
The rats were sacrificed 0.5, 1, 2, 4, 6 and 8 hours after oral or intravenous administration of 768×10-6 mol of 5-fluorouracil or 5-fluorouridylic acid, to obtain organ tissue homogenates. The bioassay technique using staphylococcus aureus 209-p was employed to know the drug concentration levels. The following results were obtained:
1. Both intravenous and oral administration of 5-fluorouracil produced almost same level of organ distribution curve, except the mucous membrane of the stomach which showed markedly high level of the drug concentration approximately 12 hours following the oral administration.
2. The oral administration of 5-fluorouridylic acid showed extremely low organ distribution curve, comparing its intravenous administration.
3. Pharmacokinetic data obtained from the two volunteer patients showed significantly high bioavailability after the oral administration of 5-fiuorouracil, in comparison with the intravenous administration.
