Bupleurum chinense (Chai Hu, Chinese: 柴胡; pinyin: chaí hú; Jyutping: caai4 wu4, Thorowax) is a plant of the family Apiaceae. Bupleurum chinense is native to East Asia. The leaves of the plant are long and thin and resemble fennel. The root of B. chinense, known as Radix Bupleuri, is used in traditional Chinese medicine. [1] .