Extracts obtained from the roots and barks of various Berberis species are used as folk remedy worldwide for the treatment of various inflammatory ailments including lumbago, rheumatism and to reduce fever. Effects of the extracts and fractions from the roots of Berberis crataegina DC. (Berberidaceae) were studied using various in vivo models of inflammation in mice and rats and observed potent inhibitory activity against carrageenan- and sero tonin -induced hind paw oedema, acetic acid-induced increased vascular permeability, castor oil-induced diarrhoea, and Freund's complete adjuvant-induced (FCA) arthritis models. Through bioassay-guided fractionation berberine was isolated as the main active ingredient. Moreover, a dose-dependent analgesic activity was determined, which assessed by using the model based on the inhibition of acetic acid-induced writhing reflexes, as well as antipyretic activity on FCA-induced increased body temperature. Acute and subchronic toxicity studies were also performed. (C) 2002 Elsevier Science Ireland Ltd. All rights reserved.