Background: Taraxacum officinale and Berberis vulgaris have long been used as herbal remedies for treatment of a variety of complaints including liver dysfunction and gallbladder disease. However scientifically reliable data are needed to verify their minimum effective doses.

Objective: In present study, the effects of Taraxacum officinale L. and Berberis vulgaris L. root extracts at the different doses 10, 20 and 30 times higher than average dose (THD) used in traditional systems of medicines were tested against carbon tetrachloride (CCl₄) induced liver toxicity in rats.

Methods: The root extracts of T. officinale at doses of 250, 500 and 750 mg/kg/day and
B. vulgaris at doses of 300, 600 and 900 mg/kg/day, relative to 10, 20 and 30 THD average doses used in traditional systems of medicines were prepared by dissolving dry extracts in 5% dimethyl sulfoxide in distilled water. Eighty male Wistar rats, 5 months old, were divided in 8 groups of 10 rats each. Liver intoxication was induced in 7 groups by intraperitoneal injection of 1 ml/kg of 1:1 CCl₄ in olive oil for two successive days. One group was kept as control and six different doses of medicinal plants extracts were administered to six groups simultaneously with CCl₄ administration. After three days the serum levels of ALT, AST and ALP, liver tissue glutathione level and catalase activities as well as liver tissue microvesicular steatosis and pericentral coagulation necrosis were determined.

Results: In control group the blood levels of ALT, AST, ALP and liver tissue injury were increased whereas the serum GSH level and catalase activity decreased significantly after 3 days of beginning of carbon tetrachloride liver toxicity as compared to normal group.

In T. officinale treated group at the dose of 750 mg/kg/day, the serum ALT and ALP levels and in B. vulgaris at the dose of 900 mg/kg/day, the serum ALP levels reduced significantly as compared to control group. The liver micro vesicular steatosis was inhibited significantly in both groups at the doses of 30 THD as compared to control group.