Male rats (200-220 g) were treated with toxic doses of carbon tetrachloride (2 mL/kg per day i.p., for 3 days) to induce liver damage. Another group of rats received kolaviron, a biflavonoid extract from seeds of Garcinia kola (500 mg/kg, i.p.) 1 h prior to receiving carbon tetrachloride. Tests for liver function were performed on all animals. The activities of glutamic oxaloacetatetransaminase (GOT), glutamic pyruvate transaminase (GPT), sorbitol dehydrogenase (SDH) and glutamic dehydrogenase (GLDH) in serum were determined, as were the concentrations of hepatic glutathione (GSH) and triglyceride in liver. Hepatic lipid peroxidation was assessed by measuring hepatic malondialdehyde (MDA) formation in the liver. Carbon tetrachloride induced marked depletion of GSH and increased the formation of MDA and triglyceride in the liver, as well as causing significant increases in activities of the serum enzymes assessed. Pretreatment with kolaviron significantly attentuated all the alterations caused by carbon tetrachloride. The antihepatotoxic action of kolaviron was clearly demonstrated in the model of hepatitis employed in this study.