Esophageal candidiasis is an opportunistic infection that is being recognized increasingly often in certain patients, including those who have a neoplastic disease, are undergoing protracted antibiotic therapy, or hae acquired immunodeficiency syndrome (AIDS). Impaired cell-mediated immunity may predispose the patient to esophageal mucosal colonization, whereas chemotherapy-induced granulocytopenia may predispose to disseminated candidiasis. Esophageal candidiasis should be suspected in susceptible patients with complaints of substernal odynophagia or dysphagia. The diagnosis is confirmed by endoscopically directed mucosal biopsy. Esophagitis from other causes (eg. herpes simplex virus, cytomegalovirus, or bacterial infection) may develop concomitantly with esophageal candidiasis. Treatment is determined by the clinical and immune status of the patient. Amphotericin B (Fungizone) is administered to immunocompromised patients at risk for disseminated or deeply invasive candidiasis and is indicated in nongranulocytopenic patients whose symptoms prevent reliable administration of oral antifungal agents. Ketoconazole (Nizoral) may be administered to clinically stable nongranulocytopenic patients with esophageal candidiasis limited to the mucosa. Patients with AIDS and a history of esophageal candidiasis usually benefit from long-term suppression with an oral antifungal agent.