The studies on concurrent administrations of herb preparations(Daesiho-tang, Daehwangmogdanpi-tang, Dohaegseunggi-tang, Baenongsangeub-tang and Jeoryeong-tang) with indomethacin and tetracycline were carried out to investigate the antiinflammatory, antimicrobial, liver-protective and antiulcer activities. The results showed that the concurrent administrations of herb preparations with indomethacin and tetracycline increased significantly the antiinflammatory activities and antimicrobial activities respectively, and also improved the liver-protective activities and antiulcer activities against indomethacin or tetracycline-induced liver defect and Shay ulcers in rats, respectively.