Active mucositis Current mucositis Any evidence of mucositis/stomatitis or previous history of severe (?Grade ) mucositis from prior therapy. Presence of any oral lesions that may confound the ability to assess oral mucositis grade Presence of oral mucositis or any oral lesion that would confound the assessment of oral mucositis Active systemic disease or condition known to impact the risk or course of oral mucositis including chronic immunosuppression and known seropositivity for HIV Patients with a current diagnosis of oral mucositis Patients with pain and oral dysfunction associated with oral mucositis despite conventional therapy Patients undergoing any other experimental intervention for oral mucositis Current mucositis. Presence of oral mucositis (WHO Score ? Grade ) at study entry At risk for mucositis OR with stage I mucositis or esophagitis (i.e. radiotherapy to the head, neck, esophagus or lung OR treatment with fluorouracil (-FU) or other chemotherapeutic agents that are known to cause mucositis or esophagitis) or at risk for xerostomia Grade or higher oral mucositis Physical exam demonstrating evidence of radiotherapy-related mucositis in the visible oral cavity and/or oropharynx consistent with mucous membrane toxicity greater than using the Acute Radiation Morbidity Scoring Criteria Patients currently receiving therapy for mucositis Enrollment in any other mucositis prevention study from screening up to day post-stem cell transplant Has oral mucositis (of any severity) prior to initiation of radiation therapy Presence of oral mucositis at study entry Current untreated oral candidiasis, oral herpes simplex virus (HSV) infection, or oral mucositis Patients enrolled on another investigational trial for oral mucositis prevention Subject has a presence of mucosal ulceration or oral mucositis at screening or develops this prior to randomization, and/or has unhealed wounds remaining from surgical resection and/or excisional biopsy procedure. Subjects with head and neck cancer involving the oropharynx or oral cavity, who are expected to undergo high dose radiation therapy (i.e., ? Gy) that typically results in oral mucositis, with or without concurrent chemotherapy or biologic targeted therapy. Are willing to refrain from using other treatments for oral mucositis until they consult with the study investigator(s). Have preexisting mucositis from other causes. Patients who currently have stomatitis/oral mucositis/mouth ulcers;