An orally bioavailable, lipophilic, triacetate prodrug form of the pyrimidine nucleoside, uridine, that can be used for uridine replacement or as an antidote for 5-fluorouracil (5-FU)-induced toxicity. Upon administration, uridine triacetate is deacetylated by esterases to produce uridine and acetate. In turn, uridine is converted to uridine triphosphate (UTP), which competes with fluorouridine triphosphate (FUTP), one of the toxic metabolites of 5-FU, for incorporation into RNA of normal cells. This prevents disruption of RNA synthesis in normal cells and limits toxicity resulting from overdose of 5-FU and 5-FU prodrugs. The FUTP-mediated damage to RNA is the main cause of 5-FU toxicities.