OUTLINE: This is a randomized, double-blind, placebo-controlled, multicenter study. Patients are stratified according to planned radiotherapy dose (less than 6,000 cGy vs at least 6,000 cGy), estimated amount of oral mucosa in the radiation field (60% or less vs more than 60%), age (under 50 vs 50 and over), concurrent chemotherapy (yes vs no), and smoking (yes vs no). Patients are randomized to 1 of 2 treatment arms.