Flurouracil
(5-FU), normally
given by IV administration (oral absorption
erratic)
Biotransformed to ribosyl-
and deoxyribosyl- derivatives.
Mechanism of
Action:
One
derivative,
5-fluoro-2'-deoxyuridine
5'-phosphate (FdUMP),
inhibits thymidylate
synthase and its
cofactor,a
tetrahydrofolate
derivative, resulting in inhibition
of thiamine nucleotide
synthesis.
Another
derivative,
5-fluorouridine
triphosphate is
incorporated into RNA,
interfering with RNA
function.
Cytotoxicity:effects
on both RNA and DNA
Clinical Use: Systemically --
adenocarcinomas; Topically: skin cancer
