[Textual study and resource investigation on traditional Chinese drugs duhuo, jiuyanduhuo and qianghuo].

By means of Bencaological study on traditional Chinese drugs Duhuo, Jiuyanduhuo and Qianghuo, it has been found out that the Duhuo recorded in earlier Bencao works should be Qianghuo, and Duhuo was first used medically in the South-North Dynasty period, whereas Jiuy-anduhuo's medical use started in the Ming Dynasty. Resources of the three drugs were investigated and their main species were found out.