The invention concerns the use of at least a molecule containing selenium, in an amount corresponding to a daily dose of about 2 to 40 mg, even 80 mg of atomic selenium equivalent, on its own or combined with other synergetic molecules for controlling oxidative stress and excessive inflammatory reaction: zinc, vitamin E, vitamin C, iron binder, glutathione precursor, copper and/or copper input binder, for preparing a medicine for treating severe systemic inflammatory response syndrome, in particular any acute infectious condition endangering the patient's life whether of bacterial, parasitic, fungal or viral origin, and any condition corresponding to a severe onset of inflammatory pathology bringing about an exacerbation of cytokine secretion. The invention is applicable in human and veterinary medicine.