A 30-year-old man and a 39-year-old women, who was 28 weeks pregnant, were simultaneously poisoned by eating chocolate containing arsenic trioxide. They developed a picture of multiple organ failure peaking around the 8th to 10th day after ingestion, with the development of life-threatening adult respiratory distress syndrome (ARDS) in both patients. This rarely reported complication of arsenic poisoning was managed successfully by intubation and mechanical ventilation with positive end expiratory pressure in both patients. Hemodynamic and laboratory data are presented supporting the clinical course. Arsenic toxicity further resulted in intrauterine fetal death. The effects of severe arsenic poisoning leading to early multiple organ failure with ARDS as well as to protracted, debilitating polyneuropathy are discussed.