Intravenous 5-fluorouracil can be delivered by rapid intravenous bolus injection or slow infusion. The vial contents can rapidly be injected directly into a peripheral vein, the commonest schedules being: 12-13.5 mg/Kg (500 mg/m2) daily for 5 days repeated at 4-weekly intervals. Slow intravenous infusion requires the drug, to be diluted in 500 ml of dextrose 5% solution, then infused over 2-3 hr on 5 successive days.

For palliative management of cancer: Initial Dose: 12 mg/kg intravenously once daily for 4 successive days. Maximum Dose: 800 mg/day. If no toxicity is observed, 6 mg/kg may be administered on the 6th, 8th, 10th, and 12th day (No therapy is given on days 5, 7, 9, or 11). Discontinue at the end of day 12, even with no apparent toxicity.

Poor risk patients and those who are not in an adequate nutritional state: Initial Dose: 6 mg/kg/day for 3 days. Maximum Dose: 400 mg/day. If no toxicity is observed, 3 mg/kg may be administered on days 5, 7, and 9 (No therapy is to be administered on days 4, 6, or 8). Discontinue at the end of day 9, even with no apparent toxicity.

Maintenance therapy: In instances where toxicity has not been a problem, it is recommended that therapy 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, administer a maintenance dose of 10 to 15 mg/kg/week as a single dose. Maximum Dose: 1g/week .The reaction by the patient to the previous course of therapy should be taken into account and the dosage should be adjusted accordingly.

Usual adult dose for cervical cancer: In combination with cisplatin 1 gm/m2 IV on day 1. The cycle is repeated every 21 days.

Usual pediatric 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.

Intra-arterial infusion: Fluorouracil has also been given by intra-arterial infusion for adult in doses of 5 to 7.5 mg/kg body weight is dissolved in 20-100 ml of 5% Dextrose solution and administered 10-20 days by using an infusion pump.

Combination with radiation: Usual adult daily dose of 5-10 mg/kg body weight is given in combination with radiation according to systemic administration method or intra-arterial infusion method.

Combination with other anticancer drugs: Fluorouracil is used alone or in combination in the adjuvant treatment of breast and gastro-intestinal cancer, and 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 every day or intermittently once to twice a week by systemic administration method or intra-arterial infusion method.