Sepsis is one of the major causes of death reported in intensive care units. A daily supplement of sesame oil for 1 week significantly attenuates oxidative stress-associated hepatic injury in septic rats. However, the excess intake of sesame oil may be associated with a health risk. This study investigates the effect of accumulative sesame oil on oxidative stress-associated hepatic injury after cecal ligation and puncture in rats. Sesame oil was administered daily (4 mL/kg/d, orally) to rats, and the total intake of sesame oil ranged from 0 (control) to 140 mL/kg before cecal ligation and puncture in 9 groups of rats. Oxidative stress was examined by determining the levels of lipid peroxidation and glutathione. Hepatic injury was evaluated by measuring serum levels of aspartate aminotransferase and alkaline phosphatase. Rats that received sesame oil for 4 and 5 weeks had a lower body weight gain compared with those that received saline. Lipid peroxidation was decreased in the 20-mL/kg and 28-mL/kg groups, but it was increased in the 140-mL/kg group compared with the control group. Glutathione levels were increased in the < or =28-mL/kg groups compared with the control group. Serum levels of aspartate aminotransferase and alkaline phosphatase were reduced in the < or =28-mL/kg groups compared with the control group. Sesame oil does not demonstrate accumulatively enhanced protection against oxidative stress-associated hepatic injury after cecal ligation and puncture in rats.