A 42 year-old man was admitted to hospital due to smoke inhalation. Thirty-three hours after admission arterial oxygen saturation was 80-90% with FiO2 = 1.0. Inhalation with prostacyclin was commenced with a dose rate of 7 ng/kg/min with an immediate effect, i.e. SATaO2 increased to 100%. Prostacyclin was terminated after 24 hours, when FiO2 was reduced to 0.5. It is concluded that prostacyclin inhalation therapy may have effect in patients following pulmonary smoke injury.