（宋开宝）
【气味】辛温，无毒。
【主治】主破血，妇人经水不调，腹中结块，崩中淋露，产后诸血病，血运，暴血冲上，
因
【核】曰∶原名玄胡索，避宋真宗讳，易玄为延也。出奚国，从安东来；奚即东北夷。
今茅山上龙洞，仁和笕桥亦种之。寒露前栽种，立春后生苗，高三四寸，延蔓布地，叶必三
之，宛如竹叶，片片成个，细小嫩绿，边色微红。作花黄色亦有紫色者。根丛生，乐蔓延，
状似半夏，但黄色耳。立夏掘起，阴干者良；锻石煮曝者，性烈不堪入药也。修事，酒润，
或醋润，蒸之，从巳至亥，俟冷取出，焙干，研细用。
先人云∶名玄而色黄，酝全气也。气温而味辛，秉金制也。以一春而备四气，叶必三之，
具木生数，象形对待肝血之非其所藏，而玄为破坚之线索无疑矣。
【 】曰∶玄者，象幽而入覆之也。荀子云∶周密则下疑玄矣。胡者，牛颔垂也，野狼亦
有之。豳风云，野狼跋其胡，载 其尾。又云，野狼 其尾，载跋其胡。索者，尽也，散也。骚
云∶凭不厌乎求索。檀弓云∶吾离群而索居，以言疾疚之证因，以言主治之功力，判属血中
之气药，气中之用药也。盖气主嘘之，血主濡之，气之所不嘘，即血之所不濡矣。如腹中结
块，募络症瘕之为证，既血留营实之为因。如胪腹气块，盘绕疝 之为证，即气滞卫实之为
因。如崩中淋露，运衄冲暴之为证，即血菀营泣之为因。如奔豚逆厥，百体疼烦之为证，即
气弛卫薄之为因。玄胡立鼓血中之气，震行气中之用，虚则补，实则平，致新推陈，推陈致
新之良物也。虽象幽入覆之如胡，凭不厌乎求索之殆尽，命名玄胡索者以此。
（有是因必有是证，因证既显，尝法已具，始可与言变矣。）
（宋开宝）
【气味】辛，温，无毒。
【主治】主要功效为破血，治疗妇女月经不调，腹中结块，崩漏（非经期大量出血及淋漓不尽），产后各种血证，血晕，以及突发性的血液上冲。
【考证】说：原名玄胡索，为避宋真宗赵恒的名讳，将“玄”改为“延”。产于奚国，从安东地区运来；奚即东北的夷族。现在茅山上的龙洞、仁和的笕桥也有种植。在寒露节气前栽种，立春后生出苗芽，高三四寸，藤蔓蔓延铺地，叶子必定是三片一组，宛如竹叶，片片分明，细小嫩绿，边缘颜色微红。开花黄色，也有紫色的。根部丛生，喜欢蔓延，形状类似半夏，只是颜色为黄色罢了。立夏时节掘起，阴干者品质优良；用锻石煮过再暴晒的，药性猛烈，不堪入药。炮制方法：用酒润湿，或用醋润湿，蒸制，从巳时到亥时，等待冷却后取出，焙干，研成细粉使用。
先父曾说：名字带“玄”而颜色黄，是酝酿了全气。气温而味辛，秉承了金的制约。用一季的时间备齐四气，叶子必定是三片，具备木的生数，象形对待肝血，说明它并非肝所藏之物，而“玄”作为破除坚积的线索，这是毫无疑问的。
【释义】说：“玄”，象征幽深而入内覆盖。“胡”，指牛下巴下垂的肉，野狼也有这种特征。《豳风》诗中说：“野狼跋其胡，载疐其尾。”又说：“野狼疐其尾，载跋其胡。”“索”，意为尽、散。《离骚》说：“凭不厌乎求索。”《檀弓》说：“吾离群而索居。”以此来说明疾病产生的原因，以此来说明主治的功效，判定它属于血中的气药，气中的血药。大概气主嘘（呼出/推动），血主濡（滋润），气所不嘘的地方，就是血所不濡的地方。如腹中结块，募络症瘕这类病症，既是血留营分、实证的原因。如胪腹气块，盘绕疝气这类病症，即是气滞卫分、实证的原因。如崩中淋露，血晕鼻衄冲暴这类病症，即是血郁营分、泣涩的原因。如奔豚逆厥，全身疼痛烦乱这类病症，即是气弛卫薄的原因。玄胡索能鼓动血中之气，震动运行气中之用，虚则补益，实则平抑，推陈致新，是推陈致新的良物。虽然像幽深入内覆盖如同“胡”，凭借不知疲倦地寻求探索直至殆尽，命名“玄胡索”正是基于此意。
（有是因必有是证，因证既显，尝法已具，始可与言变矣。）
(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.)