A materia medica work. Written by Li Gao (Dongyuan), it was completed around the mid-13th century. The contents are arranged as follows: "Methods and Phenomena of Medicinal Use," discussing the yin-yang of heaven and earth, the thickness and thinness, clarity and turbidity of medicinal properties, etc.; "Essentials of Medicinal Properties," elucidating the relationship between medicinal flavors and the ascending and descending actions, with an attached "Diagram of the Thickness and Thinness, Cold and Heat, Yin and Yang, and Ascending and Descending of Medicinal Properties"; "Ascending and Descending Represent the Meeting of Heaven and Earth's Yin Qi and Yang Qi," clarifying the relationship between ascending and descending actions and the thickness and thinness, yin and yang of medicinal properties; "Methods of Ascending, Descending, Floating, and Sinking in Medicinal Use for Supplementation and Purgation," categorizing the flavors and properties for supplementation and purgation according to zang-fu organs; "Yaolei Faxiang," classifying medicines into five categories based on wind (ascending and generating), heat (floating and growing), dampness (transforming), dryness (descending and contracting), and cold (sinking and storing), listing a hundred medicinal flavors with their properties and flavors annotated; "Discussion on Branch and Root Yin-Yang," addressing the differentiation of branch and root in medicinal use, and so on. This book further elaborates on the theory of medicinal properties, particularly emphasizing the thickness and thinness, ascending and descending actions, making it concise and easy to understand.

This book, along with another work by Li Gao titled "Methods of Medicinal Use," was cited in Wang Hao-gu's "Tangye Bencao," but no standalone edition has been found. When Li Shi-zhen's Bencao Gangmu provided an explanatory note on the book "Methods and Phenomena of Medicinal Use," it combined Yaolei Faxiang with "Methods of Medicinal Use" into one. Additionally, the "Medical Texts Examination" cites Yuan Jian's preface to "Tested Prescriptions," referring to this book as "Treatise on Medicinal Phenomena."