Different pathological processes are onvolved in sepsis.They include increased levels of free radicals and a lack of antioxidants. Free radicals are formed in sepsis from different reasons like reperfusion after ischemia, hyperglycemia, increased pathway of one-electron reduction of oxygen, increased formation in activated phagocytes, during metabolism of catecholamines, pH decrease, inflammation, activation of myeloperoxidase and liberation of some metals from their components. Nitric oxide has a special role in sepsis. In low concentrations it ameliorates the tissue perfusion, in high concentrations it has cytotoxic properties and increases the formation of peroxynitrite which evokes vascular dysfunction. The supply of antioxidants, especially ascorbic acid, selenium, glutathione and vitamin E, can be beneficial in patients with sepsis.

        Key words: sepsis, free radicals, nitric oxide, antioxidants.