Fluorouracil

Adults: Intravenous 5-fluorouracil can be given either as a rapid intravenous bolus injection or as a slow infusion. The contents of the vial can be injected rapidly and directly into a peripheral vein; the commonest schedule is 12 to 13.5 mg/kg (500 mg/m2) daily for 5 days, repeated at 4-weekly intervals. For slow intravenous infusion, the drug must be diluted in 500 ml of 5% dextrose solution and then infused over 2 to 3 hours on 5 successive days. For palliative management of cancer, the initial dose is 12 mg/kg intravenously once daily for 4 successive days, with a maximum of 800 mg per day. If no toxicity is observed, 6 mg/kg may be given on the 6th, 8th, 10th and 12th days, with no therapy given on days 5, 7, 9 or 11. Treatment is discontinued at the end of day 12, even when there is no apparent toxicity. For poor-risk patients and those who are not in an adequate nutritional state, the initial dose is 6 mg/kg per day for 3 days, with a maximum of 400 mg per day. If no toxicity is observed, 3 mg/kg may be given on days 5, 7 and 9, with no therapy given on days 4, 6 or 8. Treatment is discontinued at the end of day 9, even when there is no apparent toxicity. For maintenance therapy, in cases where toxicity has not been a problem, it is recommended that treatment be continued using either of the following schedules: repeat the dosage of the first course every 30 days after the last day of the previous course, or, when the toxic signs resulting from the initial course of therapy have subsided, give a maintenance dose of 10 to 15 mg/kg per week as a single dose, with a maximum of 1 g per week. The patient's reaction to the previous course of therapy should be taken into account and the dosage adjusted accordingly. The usual adult dose for cervical cancer is 1 g/m2 intravenously on day 1 in combination with cisplatin, with the cycle repeated every 21 days. Regarding the usual paediatric dose for malignant disease, the manufacturer has reported that the safety and effectiveness of fluorouracil have not been established in children. However, the drug has been used in children following adult guidelines. Fluorouracil has also been given by intra-arterial infusion in adults at doses of 5 to 7.5 mg/kg body weight, dissolved in 20 to 100 ml of 5% dextrose solution and administered over 10 to 20 days using an infusion pump. In combination with radiation, the usual adult daily dose is 5 to 10 mg/kg body weight, given by either the systemic administration method or the intra-arterial infusion method. In combination with other anticancer drugs, fluorouracil is used alone or in combination in the adjuvant treatment of breast and gastro-intestinal cancer, and in the palliation of inoperable malignant neoplasms, especially those of the gastro-intestinal tract, breast, head and neck, liver, genito-urinary system and pancreas. It is also used with cyclophosphamide and methotrexate in the combination chemotherapy of breast cancer. A usual adult dose of 5 to 10 mg/kg body weight daily is given in combination with other anticancer drugs, either every day or intermittently once to twice a week, by the systemic administration method or the intra-arterial infusion method.