Study to Determine the Effects Treatment With Amlexanox 0.5% Oral Rinse Solution on Oral Mucositis Associated With Radiation Therapy for Cancer of the Head and Neck Region

Inclusion Criteria: 1. Patient is 18 years of age or older; 2. Patient has a histologically documented diagnosis of cancer of the head and neck region; 3. Patient is about to receive a course of radiation therapy (with or without concomitant chemotherapy) with a planned dose of at least 60 Gy over 6-7 weeks, and with planned fields to involve at least 50% of the oral mucosa; This criterion was amended (Amendment 01 dated August 28, 2000) to read as follows: 3\. Amended: Patient is at a high risk of developing radiation-induced mucositis. For the purpose of this study, high-risk patients will be defined as: 1. patients about to receive a course of radiation therapy (with or without concomitant chemotherapy) with a planned dose of at least 60 Gy over 6-7 weeks, and 2. with planned fields to involve at least 40% of the oral and oropharyngeal mucosa visible by direct inspection; 4\. Patient has a Karnofsky Performance Scale (KPS) score of 60% or more; 5\. Patient is willing and able to cooperate with the protocol including rinsing of the oral cavity with the investigational or vehicle oral rinse 6 times per day. 6\. The patient or guardian is capable of providing informed consent. 7\. If female, the subject has undergone a urine pregnancy test with negative results, and has agreed to practice effective methods of contraception for the duration of the study. Exclusion criteria 1. Patient has had previous radiation therapy to the oral mucosa; 2. Patient is about to receive hyperfractionated radiation therapy; 3. Patient has active oral H. simplex lesions, oral candidiasis, or oral mucositis due to other disease processes; 4. Patient has uncontrolled infection; 5. Patient has HIV, Hepatitis B (HBV) (as measured by HBs-Ag) or Hepatitis C (HCV) infection; 6. Patient has not recovered from oral toxicity attributable to prior treatment; 7. Patient has abnormal laboratory values that meet the following criteria: * Serum creatinine greater than 2 x upper limit of normal * Total bilirubin greater than 3 x upper limit of normal; * SGOT greater than 3 x upper limit of normal; * LDH greater than 3 x upper limit of normal; 8. Patient has known sensitivities to any of the study preparation ingredients; 9. Patient has participated in a clinical research study within the last 30 days prior to enrollment; 10. Patient is unable to communicate or cooperate with the investigator due to language problems, poor mental development, or other reasons.