Severe hemorrhagic pancreatitis developed in a patient with the acquired immunodeficiency syndrome (AIDS) during pentamidine isethionate treatment for Pneumocystis carinii pneumonia. Despite prompt withdrawal of administration of the drug, the patient died of complications of pancreatitis. Pentamidine is known to be toxic to pancreatic islet cells, causing both hypoglycemia and hyperglycemia in clinical use. However, it rarely causes symptomatic pancreatitis. A review of the literature indicates that this is the second report of fatal pancreatitis associated with pentamidine therapy.