A method for treatment of severe diffuse acute respiratory distress syndrome in an intubated-ventilated patient which includes sedating said patient with at least one alpha-2 agonist, maintaining spontaneous ventilation and applying pressure support ventilation of at least 5-10 cmH2O combined to a high positive end expiratory pressure (PEEP) of 10-24 cmH2O. A pharmaceutical composition containing at least one alpha-2 agonist suitable for treatment of ARDS in combination with, if appropriate, at least one sedative agent which does not depress ventilatory drive is also disclosed.
