AbstractSnake venoms present different action mechanisms because of their complex composition, represented mainly by toxins and enzymes. This work aimed to investigate the effects of the Crotalus durissus terrificus(Cdt) venom in the liver. Wistar rats were inoculated intraperitoneally with saline (control) or Cdt venom. After 3, 4, or 6 h, the following parameters were analyzed: (a) hepatic function, (b) oxidative stress parameters, and (c) the metabolism of alanine in the isolated perfused liver. Plasma activities of alanine aminotransferase and aspartate aminotransferase and hepatic glutathione S‐transferase and catalase presented significant elevation in rats inoculated with 300 μg ⋅ kg−1 Cdt venom. Liver lipoperoxidation was enormously increased by venom doses of 100, 200, and 300 μg ⋅kg−1, whereas glutathione S‐transferase was not changed. Perfused livers from rats inoculated with 1500 μg ⋅kg−1 venom showed increased production of lactate, pyruvate, and ammonia when alanine was the metabolic substrate. These results demonstrate that the Cdt venom can produce several changes in hepatocytes. The causes of the changes are possibly related to the disequilibrium in the redox homeostasis but also to specific needs of the poisoned organism, for example, an increased supply of lactate and pyruvate in response to an increased activity of the Cori cycle. © 2010 Wiley Periodicals, Inc. J Biochem Mol Toxicol 25:195–203, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/jbt.20376