In this communication, we document the antioxidant potential of ethanolic extract of Rumex patientia L. (Polygonaceae) roots and its chemopreventive effects against Fe-NTA mediated hepatic oxidative stress, hepatotoxicity and tumor promotion response. The extract exhibited high polyphenolic content, potent reducing power and significantly scavenged free radicals (including several reactive oxygen species (ROS) and reactive nitrogen species (RNS)). The extract also significantly and dose dependently protected against oxidative damage to lipids and DNA. These results indicated R. patientia root extract to exert a potent antioxidant activity in vitro. The efficacy of extract was also evaluated in vivo and it was found to exert a potent protective affect in acute oxidative tissue injury animal model: ferric nitrilotriacetate (Fe-NTA) induced hepatotoxicity in mice. Administration of Fe-NTA (9 mg/kg body weight, i.p.) to mice led to a significant oxidative stress and allied damage in liver tissues and induced hyperproliferation. A significant depletion was observed in GSH content and enzymes implicated in its metabolism. Attenuation also occurred in activities of other hepatic antioxidant enzymes including SOD, CAT, and GPX. Fe-NTA also incited hyperproliferation response elevating ornithine decarboxylase activity and [3H]-thymidine incorporation into DNA. Histopathological investigations and liver function tests (LFT) indicated Fe-NTA to cause extensive hepatic damage. However, prophylactic treatment with R. patientia root extract at a dose regimen of 100-200 mg/kg body weight for a week not only restored hepatic antioxidant armory close to normal, but also significantly precluded oxidative damage restoring normal hepatic architecture and levels of hepatic damage markers. The data obtained in the present study illustrates R. patientia roots to possess potent antioxidant and free radical scavenging activities and thwart oxidative damage and hyperproliferation in hepatic tissues. © 2007 Elsevier Ltd. All rights reserved.