Library

(Song Kaibao)
[Flavor and Nature] Pungent, warm, non-toxic.
[Indications] Primarily breaks blood stasis; treats irregular menstruation in women, abdominal masses, metrorrhagia and metrostaxis (abnormal uterine bleeding), postpartum blood disorders, syncope due to blood loss, and sudden upward rushing of blood.

[Examination] It is said: Originally named Xuanhusuo (Corydalis Rhizome), the character "Xuan" was changed to "Yan" to avoid the naming taboo of Emperor Zhenzong of Song. It originates from the Xi country, arriving from Andong; Xi refers to the Yi people of the northeast. Currently, it is also cultivated at Longdong on Maoshan Mountain and Jianqiao in Renhe. It should be planted before the Cold Dew solar term, and seedlings emerge after the Start of Spring. The vines grow three or four cun high, spreading over the ground. The leaves are invariably in groups of three, resembling bamboo leaves, distinct segments, small, tender green, with slightly red edges. The flowers are yellow, sometimes purple. The roots grow in clusters and love to spread, resembling Pinelliae Rhizoma Preparatum (Banxia) but yellow in color. It is dug up at the Start of Summer; those dried in the shade are of good quality. Those boiled with calcined iron ore (Duan Shi) and then sun-dried have a fierce nature and are unsuitable for medicinal use. Processing method: Moisten with wine or vinegar, steam from Si hour (9-11 AM) to Hai hour (9-11 PM), wait until cool, take out, bake dry, grind into fine powder for use.

My late father said: Named "Xuan" (dark/mysterious) but yellow in color, it brews complete Qi. Warm in temperature and pungent in flavor, it embodies the constraint of Metal. In one season, it prepares all four natures; the leaves are invariably in threes, possessing the generating number of Wood. By form and correspondence to Liver Blood, it indicates that it is not what the Liver stores, and "Xuan" serves as the clue for breaking hard accumulations, which is beyond doubt.

[Explanation] It is said: "Xuan" symbolizes entering deeply and covering like darkness. "Hu" refers to the dewlap of an ox, which wild wolves also possess. The Book of Songs (Odes of Bin) states: "The wild wolf treads on its dewlap, stumbling on its tail." It also says: "The wild wolf stumbles on its tail, treading on its dewlap." "Suo" means exhaustion or scattering. The Li Sao (Encountering Sorrow) states: "Relying on endless seeking and searching." The Tan Gong chapter of the Book of Rites states: "I leave my group and seek solitary dwelling." This explains the cause of disease symptoms and the efficacy of treatment, determining it to be a Qi medicine within Blood, and a Blood medicine within Qi. Generally, Qi governs exhaling/pushing, while Blood governs moistening. Where Qi does not push, Blood does not moisten. For example, abdominal masses, abdominal wall phlegm-stasis and tumor formations as syndromes, are caused by blood stagnating in the Ying (Nutritive) level becoming excess. For example, abdominal gas masses, coiling hernias as syndromes, are caused by Qi stagnation in the Wei (Defensive) level becoming excess. For example, metrorrhagia and metrostaxis, syncope, epistaxis, and sudden violent rushes as syndromes, are caused by blood depression in the Ying level causing sluggishness. For example, running piglet syndrome, counterflow cold limbs, and whole-body pain and irritability as syndromes, are caused by Qi relaxation and thinning of the Wei level. Yanhusuo can stir the Qi within Blood and activate the function of Qi within Blood. For deficiency, it tonifies; for excess, it pacifies. It eliminates the old and generates the new, making it an excellent substance for eliminating the old to generate the new. Although it resembles the dark covering like "Hu," and relies on tireless seeking until exhaustion, naming it "Yanhusuo" is based on this meaning.
(Where there is a cause, there must be a corresponding syndrome. Once the cause and syndrome are manifest, and empirical methods are established, only then can one discuss variations.)