SUMMARY
The results of 123 patients with acute peritonitis were analyzed. All patients were operated in toxic and terminalphases. The indicators of intoxication and enzyme activity of antioxidant system were estimated within 6 hours, 1 and3 days after surgery treatment. As result of this investigation was confirmation that one of the factors homeostasisviolations in peritonitis is activation of peroxide lipid – diene conjugates, TBA-active products in the blood and reducethe activity of antioxidant system – glutathione peroxidase, catalase, glucose-6-phosphate dehydrogenase andglutathione reductase as main branch of antiradikal and antiperoxidative protection.