The present study was designed to evaluate the anti-asthmatic activity of aqueous extract of flowers of Achillea mellifolium Linn. belonging to the family Asteracae (Compositae). The antiasthmatic activity of the extract 5, 10, 15, 20, 25, 30mg/ml was evaluated in guinea pig ileum, guinea pig trachea chain, rat ileum, rat fundus isolated preparations by using standard drugs Histamine, Acetyl Choline & 5- HT respectively. The extract significantly inhibited all the response produced by the inflammatory mediators used and maximum significant anti-asthmatic activity was observed at the doses of 25, 30 mg/ml.
