Pathophysiology, monitoring, and management of the ventilator-dependent patient: considerations for drug therapy, emphasis on stress ulcer prophylaxis. Adult respiratory distress syndrome (ARDS), or noncardiac pulmonary edema, is a form of acute hypoxemic respiratory failure. The goals of treatment for patients with ARDS are to provide supportive therapy, to reverse the underlying etiology or pathology, and to prevent subsequent complications. Supportive therapy consists of supplemental oxygen, positive end-expiratory pressure, and, often, mechanical ventilation. The reversal of the underlying pathology varies according to the etiologic origin of ARDS. Complications from ARDS include stress ulcers, which occur when gastric aggressive and defensive functions become unbalanced. Antacids and cytoprotective agents are used for stress ulcer prophylaxis, but histamine H2-receptor antagonists are now regarded as the standard of care. Because all the marketed H2-receptor antagonists are efficacious, choice of the agent is based on the adverse effect profile and drug interactions. No definitive data currently exist linking stress ulcer prophylaxis regimens that raise intragastric pH to a significant risk for nosocomial pneumonia. 