Oral mucositis is a frequently encountered and potentially severe complication associated with administration of chemotherapy and radiotherapy. Although many pharmacologic interventions have been used for the prevention and treatment of oral mucositis, there is not one universally accepted strategy for its management. Most preventive and treatment strategies are based on limited, often anecdotal, clinical data. Basic oral hygiene and comprehensive patient education are important components of care for any patient with cancer at risk for development of oral mucositis. Nonpharmacologic approaches for the prevention of oral mucositis include oral cryotherapy for patients receiving chemotherapy with bolus 5-fluorouracil, and low-level laser therapy for patients undergoing hematopoietic stem cell transplantation. Chlorhexidine, amifostine, hematologic growth factors, pentoxifylline, glutamine, and several other agents have all been investigated for prevention of oral mucositis. Results have been conflicting, inconclusive, or of limited benefit. Treatment of established mucositis remains a challenge and focuses on a palliative management approach. Topical anesthetics, mixtures (also called cocktails), and mucosal coating agents have been used despite the lack of experimental evidence supporting their efficacy. Investigational agents are targeting the specific mechanisms of mucosal injury; among the most promising of these is recombinant human keratinocyte growth factor.