The appropriate timing and dosage of Fluorouracil (5-FU) for a patient undergoing hemodialysis should be carefully considered due to the altered pharmacokinetics in these patients. In a case report of a patient with gastric cancer and chronic renal failure treated with 5-FU/leucovorin (LV) infusion chemotherapy, hyperammonemia was managed by adjusting the timing of hemodialysis. Initially, the patient developed symptomatic hyperammonemia and underwent emergency hemodialysis on day 3. In subsequent cycles, the 5-FU dose was reduced, but hyperammonemia persisted, requiring hemodialysis on day 3. By changing the scheduled hemodialysis from day 3 to day 2, symptomatic hyperammonemia was prevented in cycles 5-7.
Although there are no set recommendations for dose adjustment of 5-FU in the presence of renal or hepatic dysfunction, it is crucial to monitor patients closely for adverse events and adjust the treatment regimen accordingly. In the case report mentioned above, the 5-FU dose was reduced, and the timing of hemodialysis was adjusted to manage hyperammonemia. Further studies with more cases are needed to determine the optimal dosage and timing of hemodialysis for patients with impaired renal function receiving 5-FU treatment.
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