Abstract: Objective To investigate the origin, concoction and toxicity of the toxic herb Kansui Radix, and to provide reference for research application. Methods This study made a systematic textual research on the historical evolution and changes of the name, origin, producing areas, harvesting time, processing methods and toxicity of Kansui Radix, compared them, and explored them in depth with modern literature. Results The name, origin and efficacy of Kansui Radix had not changed significantly during its historical development. Kansui Radix was a toxic herb, in order to reduce the toxicity and ensure the safety of the medicine, a variety of processing methods had been recorded in the various ancient documents. Kansui Radix was the "holy medicine of draining water", it was toxic and should not be used on the weak. It should not be taken excessively, and it should be stopped when it was sick. Conclusion By examining the Chinese herbal medicine Kansui Radix, we can identify the history of its use, avoid poisoning in clinical use, and lay the foundation for regulating the market circulation and unifying its use.

Key words: Kansui Radix, textual research on materia medica, origin, geoherbalism, processing methods, toxieity of Chinese materia meelica