Decreased Oral Toxicity with the Local Use of Allopurinol in Patients Who Received High Dose 5-Fluorouracil

5–Fluorouracil (5FU) is the most effective drug in gastrointestinal cancer.Mucositis and bone narrow toxicity are the two major Uniting side effects.In our effort to reduce mucositis we administered Allopurinol mouthwash in 42 patients who had experienced oral mucositis during prior treatment with 5FU.In all patients significant reduction of oral toxicity was noticed as well as prolonged pain relief.