Prodrug of Fluorouracil: hydrolyzed in the liver to form fluorouracil, which is the active compound (see 5-Fluorouracil, 5-Fluorouracil)
5-Fluorouracil is a Fluorinated Pyrimidine Antimetabolite Which Inhibits Thymidylate Synthetase: blocks the methylation of deoxyuridylic acid to thymidylic acid, interfering with DNA synthesis (and to a lesser extent, RNA synthesis)
5-Fluorouracil appears to be phase-specific for the G1 and S phases of the cell cycle
Metabolism
Hepatic: to inactive metabolites 5′-deoxy-5-fluorocytidine and 5′-deoxy-5-fluorouridine
Tissue: enzymatically metabolized to fluorouracil –> this is then metabolized to the active metabolites, 5-fluoxyuridine monophosphate (F-UMP) and 5-5-fluoro-2′-deoxyuridine-5′-O-monophosphate (F-dUMP)
Elimination Half-Life: 0.75 hr
Administration
PO:
Dose Adjustment
Hepatic
Mild-Moderate Impairment: no dose adjustment necessary