出陕西州郡及河阳。其木似檀。枝干皆青绿。叶细如匙。虚大不光。并无花实。皮上有
白点。
味苦。气寒微。沉也。降也。入足厥阴少阳经。 大戟为之使。恶吴茱萸。 主治风寒
湿痹洗洗寒气。（如冷水浇）洗肝益精。除热。疗目中青翳白膜。去两目赤肿疼痛。久热风
泪不止。治热痢下重。下焦虚。疗妇人崩带。作汤浴小儿惊痫风热。秦皮水浸。即青碧。青
入肝。风邪为病。先见于色。当为肝之风药。
〔论〕 本经秦皮首主风寒湿痹。洗洗寒气除热。是所谓除热者。即其散风寒湿之痹。
不致郁而为热也。继云疗目中青翳白膜。夫东垣论青白翳有曰。阴盛阳虚。则九窍不通。令
青白翳见于大 。乃足太阳少阴经中郁遏。厥阴肝气。不得上通于目。故青白内阻也。以此
相证。则秦皮退热之功。不专散肝经之风寒湿痹哉。日华子定其用曰洗肝。为能祛寒水之阴
以达阳。不致郁而为热。得还其敷和之平气也。故伤寒传经至厥阴。仲景用此为主药。可谓
得先圣之精诣矣。（传经之热。正因寒郁。）别录疗男子少精。妇人带下。何以明之。张子和
曰。冲任督三脉。同起而异行。一源而三歧。皆属带脉。因诸经上下往来。遗热于带脉之间。
客热郁抑。遂致白物淫溢。男子因溲而下。女子绵绵而下也。经曰。带脉起于季肋足厥阴之
章门穴。同足少阳循带脉穴。围周一身。如束带然。若是。则带下之病。焉得不取责于肝乎。
夫冲任督皆本于肾。皆以肝行其化。秦皮达其阴之郁阳者。即能祛其阳之伤阴者。如带下之
疗。在除湿热。即本经达风寒湿痹之气。而便以除热之治也。粗工漫同苦寒之味言其退热。
岂知本经止言其气微寒。而甑权又言气平。不依然敷和之春气哉。至于男子益精。当思冲任
督俱起于肾。俱行化于肝。以默识此味之功矣。经曰。两神相搏谓之精。两神者。阴阳二气
也。肝以一阴为独使。下合于任。上会于督。阴阳之相搏 也。岂其微哉。（肝得行其化。
则阴中之阳。所谓元气者自盛。气盛则精盈。修真家亦是此理。）
〔辨治〕 去骨取皮。渍水。水色侵碧。书纸纸面略青者真。
秦皮产于陕西各州郡以及河阳。它的木材类似檀香木，枝干都呈青绿色。叶子细小像汤匙一样，质地疏松大而表面不光亮，没有花朵和果实。树皮上有白色的斑点。
味道苦，气微寒，性质沉降，作用趋势向下。归入足厥阴肝经和足少阳胆经。大戟（Euphorbiae Pekinensis Radix）作为其引经药。忌与吴茱萸（Evodiae Fructus）同用。
主要治疗风寒湿痹症引起的阵阵寒冷感（如同冷水浇身）。清肝明目、益精，清除热邪，治疗眼睛中出现的青翳和白膜，去除双眼红肿疼痛，治疗久风引起的迎风流泪不止。治疗热痢伴有里急后重，下焦虚损，治疗妇女崩漏和带下病。煎汤外洗可治疗小儿惊痫及风热证。秦皮用水浸泡后，水色变为青碧色。青色入肝，风邪致病，首先从面色上显现出来，因此秦皮应当被视为治疗肝经风证的药物。
〔论述〕《神农本草经》记载秦皮首先主治风寒湿痹，消除阵阵寒气并退热。所谓的“除热”，是指它疏散风寒湿邪导致的痹阻，防止郁结而化热。接着说治疗眼睛中的青翳和白膜。李东垣在论述青白翳时曾说：阴盛阳虚，则九窍不通，导致青白翳出现在眼中，这是由于足太阳膀胱经和足少阴肾经中郁遏阻滞，厥阴肝气不能上通于目，所以青白之气在内阻隔。以此相互印证，那么秦皮退热的功效，不仅仅是疏散肝经的风寒湿痹罢了。日华子确定了它的作用为“洗肝”，是因为它能祛除寒水之阴以通达阳气，不致郁结化为热邪，从而恢复肝脏敷和的平和之气。所以伤寒病传经至厥阴经时，张仲景使用此药为主药，可以说是深得古代圣人的精妙造诣了。（传经之热，正是因为寒邪郁结所致。）《名医别录》记载治疗男子少精、妇人带下。如何解释这一点呢？张子和说：冲脉、任脉、督脉这三条经脉，同源而异行，一源分为三歧，都属于带脉管辖。因为各经脉上下往来，将余热遗留在带脉之间，客热郁抑，于是导致白色分泌物淫溢，男子因小便而下出，女子绵绵不断地下流。经书说：带脉起于季肋部的足厥阴肝经章门穴，与足少阳胆经循行经过带脉穴，环绕身体一周，像束带一样。如果是这样，那么带下的疾病，怎么能不归责于肝呢？冲脉、任脉、督脉都本源于肾，都由肝来行使气化功能。秦皮能疏通肝阴中的郁滞阳气，也就能够祛除损伤阴液的阳热之邪。如治疗带下，在于除湿热，这也就是《本经》所说的疏通风寒湿痹之气，进而达到除热的治疗效果。粗疏的医生随意用苦寒的味道来说明它退热的作用，哪里知道《本经》只说它气微寒，甄权又说它气平，这不依然符合敷和的春天气息吗？至于男子益精，应当想到冲、任、督三脉都起于肾，都在肝进行气化，以此来默识此药的功用。经书说：两神相搏称为精。所谓两神，就是阴阳二气。肝以一阴之气作为独使，下合于任脉，上会于督脉，阴阳二气的相搏，难道不重要吗？（肝能够行使气化功能，那么阴中之阳，也就是所谓的元气就会旺盛，气旺盛则精充盈，修真家也是这个道理。）
〔鉴别与治疗〕去掉木质部分取用树皮，用水浸泡，水色呈现青碧色，用来书写纸张，纸面略微发青的才是真品。
Qinpi (Fraxinus Cortex) originates from various prefectures in Shaanxi and Heyang. Its wood resembles that of sandalwood, with branches and trunks all appearing greenish-blue. The leaves are slender like spoons, loose and large but not glossy, lacking flowers and fruits. There are white spots on the bark.
It tastes bitter and has a slightly cold nature. It is heavy and descending, entering the Foot-Jueyin Liver Meridian and Foot-Shaoyang Gallbladder Meridian. Dajixie (Radix Euphorbiae Pekinensis) serves as its guiding herb. It is incompatible with Wuzhuyu (Fructus Evodiae).
It primarily treats Bi syndrome caused by wind-cold-dampness, characterized by a chilling sensation (as if cold water were poured on the body). It clears the liver, benefits essence, eliminates heat, treats green nebula and white membrane in the eyes, removes redness, swelling, and pain in both eyes, and treats persistent tearing due to chronic wind. It treats dysentery with tenesmus, deficiency of the Lower Jiao, leukorrhea and metrorrhagia in women, and pediatric convulsions and wind-heat when decocted for bathing. When Qinpi is soaked in water, the water turns blue-green. Blue enters the Liver; since wind-pathogens manifest first in complexion, Qinpi should be regarded as a herb treating Liver wind.
[Discussion] The *Shennong Bencao Jing* states that Qinpi primarily treats Bi syndrome due to wind-cold-dampness, eliminating chilling sensations and clearing heat. The so-called "clearing heat" refers to dispersing the obstruction of wind-cold-dampness, preventing it from stagnating and transforming into heat. It further mentions treating green nebula and white membrane in the eyes. Li Dongyuan discussed green and white nebulae, stating: "When Yin is excessive and Yang is deficient, the nine orifices become blocked, causing green and white nebulae to appear in the eyes. This is due to stagnation in the Foot-Taiyang Bladder Meridian and Foot-Shaoyin Kidney Meridian, where the Qi of the Jueyin Liver cannot ascend to the eyes, thus obstructing the interior with green and white pathogenic factors." Corroborating this, the heat-clearing efficacy of Qinpi is not limited to merely dispersing wind-cold-dampness Bi in the Liver Meridian. Ri Huazi defined its function as "washing the liver," meaning it dispels the Yin of cold-water to reach Yang, preventing stagnation and transformation into heat, thereby restoring the harmonious and mild Qi of the Liver. Therefore, when Typhoid fever transmits to the Jueyin stage, Zhang Zhongjing used this herb as the principal ingredient, truly mastering the profound insights of the ancient sages. (The heat transmitted via meridians is precisely due to cold stagnation.) The *Mingyi Bielu* records its treatment of scanty essence in men and leukorrhea in women. How is this explained? Zhang Zihe said: "The Chong, Ren, and Du meridians originate from the same source but diverge in their pathways; they form one source branching into three, all belonging to the Dai Meridian. As the various meridians travel up and down, they leave residual heat within the Dai Meridian. Guest heat stagnates, leading to an overflow of white discharge, which exits through urination in men and flows continuously in women." The classics state: "The Dai Meridian originates at Zhangmen (LR13) on the hypochondrium of the Foot-Jueyin Liver Meridian, running along the Daibao point of the Foot-Shaoyang Gallbladder Meridian, encircling the body like a belt." In this manner, how can leukorrhea not be attributed to the Liver? The Chong, Ren, and Du meridians originate from the Kidney and undergo transformation via the Liver. Qinpi unblocks the stagnant Yang within Yin, thereby dispelling the Yang heat that damages Yin. For instance, treating leukorrhea involves removing damp-heat, which aligns with the *Bencao Jing*'s description of unblocking wind-cold-dampness Bi to achieve heat clearance. Crude practitioners casually attribute its heat-clearing effect to its bitter-cold taste, failing to realize that the *Bencao Jing* only describes its nature as slightly cold, and Zhen Quan described it as neutral, consistent with the harmonious spring Qi. Regarding benefiting essence in men, one must consider that the Chong, Ren, and Du meridians originate in the Kidney and transform in the Liver, thereby understanding the merit of this herb. The classics say: "The interaction of two spirits is called Essence." The two spirits refer to Yin and Yang Qi. The Liver acts as the sole envoy of Yin, connecting downward with the Ren Meridian and upward with the Du Meridian. The interaction of Yin and Yang is significant. (When the Liver functions properly, the Yang within Yin, known as Yuan Qi, becomes robust; robust Qi leads to abundant Essence, a principle also recognized in Daoist cultivation.)
[Differentiation and Treatment] Remove the woody core and use only the bark. Soak in water; if the water turns blue-green and writing on paper results in a slightly bluish surface, it is authentic.