Patients will be excluded from participation if taking any concurrent treatment for mucosal lesions (including topical or systemic steroids, viscous lidocaine, topical or systemic anti-fungals, or mouthwashes), prior to concurrent thalidomide therapy, chemotherapy or radiation therapy for neoplasms, concurrent acute therapy for opportunistic infection, concurrent use of sedatives (such as CNS depressants or alcohol use), history of allergy to thalidomide, pre-existing peripheral neuropathy of grade II or higher, and females of childbearing potential.