Study of the Effectiveness of Cevimeline on Oral Health in Patients With Radiation Induced Xerostomia

Inclusion Criteria: * Subject is at least 18 years old and able to give written informed consent * Subject has received external beam radiotherapy \> 4000 cGy for SCCA of the head and/or neck * Radiation therapy was completed at least 16 weeks (4 months) prior to enrollment into the study but not greater than 52 weeks (12 months) * Radiation included at least three of four of the major salivary glands (submandibular and parotid glands) in the initial field (boost fields may or may not include the parotid gland) * Primary therapy was designed with curative intent. Surgery is permitted if the remaining inclusion criteria are met * Grade 1 or 2 xerostomia by CTC version 3.0 criteria (Appendix D) * Demonstratable salivary flow as assessed by the clinician after administration of a potent sialogogue such as lemon juice (1 teaspoon) * Subject has at least one anatomically intact parotid gland and one submandibular gland * ECOG performance status of 0, 1, or 2 * An EKG obtained has been performed in the past 6 months showing no arrhythmias or contraindication to administration of a muscarinic agent AND there has been no interval change in cardiac health * Subject is able to eat an oral diet to maintain adequate hydration and nutrition * Subject has provided informed consent * Subject is English speaking and of sufficient mental capacity to comply with the study requirements * Female subjects of child bearing potential have a negative serum pregnancy test and agree to use an approved method of birth control Exclusion Criteria: * Subject has a life expectancy less than 12 months. * Subject is known or suspected to have persistent disease after curative intent * Subject is greater than 12 months out from completion of radiation therapy * Subject is pregnant or nursing * Subject had previous cancer of the head and/or neck and is being treated with a second course of radiation therapy * Subject has a history of an autoimmune disease with pretreatment xerostomia (i.e. Sjogrens) or other underlying systemic illness known to cause xerostomia independent of prior radiation therapy exposure * Subject has had resection of both parotid glands * Subject has history of cardiomyopathy or untreated moderate to severe CAD * Subject has known cardiac arrhythmias * Subject has grade 3 xerostomia (CTC v.3)or no demonstratable salivary flow after the test dose by visual inspection * Subject has history of significant renal or hepatic impairment * Subject uses a gastrostomy tube for nutrition supplementation * Subject is taking medications specified in Appendix C * Subject is taking or has taken any investigational new drug within the last 30 days or is planning to take such a drug during the course of this study * Subject has a contraindication to administration of muscarinic medications. * Subject has been treated previously with a muscarinic agent for xerostomia (i.e., Pilocarpine HCl)