黄之为色，血与水和杂而然也。人身血管、液管，相副而行，不相淆乱者，各有管以束
之也
。血分湿热熏蒸，肌理缓纵，脉管遂弛而不密，血遂渗出，与液相杂，映于肤，泄于汗，而
莫不黄。故治之法，或汗或下，必以苦寒清燥，佐入行瘀之品，为摄血分之湿热而宣泄之也
。湿热去则脉管复坚，血液各返其道，而清浊分矣。阴黄者，以其本体内寒也，虚阳外菀，
与湿相搏肌肉腠理之间，仍自湿热，非寒能成黄也。阳黄色深浓者，热盛则津液蒸腐，化为
黄粘之汁，与血相映，故色浓也；阴黄色暗淡者，无根之热，不能蒸腐津液，尽化稠粘，而
水多于血，故色淡也。夫血之所以旁渗者，以血既为湿所停凝，而前行有滞，气又为热所逼
迫，而横挤有力，加以肌理松弛，而血因之旁渗矣。蓄血发黄，亦此理也。《内经》谓瘅成
为消中，湿热菀久而化燥火也，亦有消成为瘅者。燥火得凉润滋清之剂，已杀其势，未净其
根，余焰内灼，转为湿热也。
黑疸，乃女劳疸、谷疸、酒疸日久而成，是肾虚燥而脾湿热之所致也。肾恶燥而脾恶湿
，肾
燥必急需他脏之水精以分润之，适值脾湿有余，遂直吸受之，而不觉并其湿热之毒。而亦吸
入矣。脾肾浊气，淫溢经脉，逐日饮食之新精，亦皆为浊气所变乱，全无清气挹注，周身血
管，不得吐故纳新，遂发为晦暗之黑色矣。第微有辨焉∶其肾水不甚虚，而脾胃自虚，浊气
下溜者，病在中焦，为易治也；其色黑而浮润，肾水虚甚，吸受脾之浊气，如油入面，深不
可拔，病在下焦，其色黑而沉滞。治中焦者，清胃疏肝，滋肾利水，即小柴胡、茵陈五苓是
也；阴黄者，黄连枳实诸理中汤主之。治下焦者，滋肾补肺，不得清胃，更不得利水，滋肾
丸、大补阴丸加参、 可也，必待肺气已充，肾阴已复，始从清胃利水；若阴黄者，茵陈四
逆主之。总须兼用化血之品一二味，如桃仁、红花、茜草、丹参之类。为其已坏之血不能复
还原质必须化之，而后无碍于新血之流行也。
黄疸的颜色，是血液与津液混合混杂而形成的。人体的血管和液管并行运行，互不混淆，是因为各有管道约束它们。血分中的湿热熏蒸，导致肌理松弛，脉管随之弛缓而不紧密，血液于是渗出，与津液相混杂，映照在皮肤上，排泄于汗液中，因而无不呈现黄色。所以治疗的方法，或采用发汗法，或采用泻下法，必须使用苦寒药物以清热燥湿，并佐入活血化瘀的药物，以此来摄取并宣泄血分中的湿热。湿热去除后，脉管恢复坚实，血液各自回归正常通道，清浊便分离了。阴黄，是因为患者本身体内有寒，虚阳外越郁结，与湿气搏结于肌肉腠理之间，仍然表现为湿热，并非寒气能直接导致发黄。阳黄颜色深浓的，是因为热盛导致津液被蒸腾腐化，转化为黄色的粘稠汁液，与血液相互映照，所以颜色深浓；阴黄颜色暗淡的，是无根之火，不能蒸腾腐化津液使其全部化为稠粘之物，而是水多于血，所以颜色淡。血液之所以旁渗，是因为血液已被湿气停滞凝结，前行受阻，气又受到热的逼迫，横向挤压有力，加上肌理松弛，血液因此旁渗。蓄血发黄，也是这个道理。《内经》说瘅疾发展为消中（多食易饥），是湿热郁久化燥火所致，也有消中发展为瘅疾的情况。燥火得到凉润滋清的药剂治疗后，势头已减，但病根未净，余焰在内灼烧，转而变为湿热。
黑疸，是由女劳疸、谷疸、酒疸日久演变而成，这是肾虚干燥与脾脏湿热共同作用的结果。肾厌恶干燥而脾厌恶湿气，肾燥必然急需其他脏腑的水精来滋润，恰逢脾湿有余，于是直接吸收脾湿，却不自觉地将其中湿热的毒邪也一并吸收了。脾肾的浊气淫溢于经脉之中，使得每日饮食所化的新精微物质，也被浊气扰乱，完全没有清气注入，周身血管无法吐故纳新，于是呈现出晦暗的黑色。这里稍微加以辨别：如果肾水不是很虚，而是脾胃自虚，浊气下流的，病在中焦，容易治疗；如果颜色黑且浮润，肾水虚损严重，吸收脾之浊气，如同油渗入面中，深入不可拔除，病在下焦，其色黑且沉滞。治疗中焦的，用清胃疏肝、滋肾利水的方法，即小柴胡汤、茵陈五苓散等方剂；对于阴黄，用黄连、枳实等组成的理中汤类方剂主治。治疗下焦的，用滋肾补肺的方法，不得清胃，更不得利水，可用滋肾丸、大补阴丸加人参、（缺字，推测为某药或泛指），必须等到肺气已充盛，肾阴已恢复，才开始从清胃利水入手；如果是阴黄，用茵陈四逆汤主治。总之必须兼用一二味化瘀血的药物，如桃仁、红花、茜草、丹参之类。因为已经败坏的血液不能恢复原质，必须将其化解，然后才不影响新血的流行。
The color of jaundice is formed by the mixing and blending of blood and body fluids. The blood vessels and fluid vessels in the human body run parallel to each other without confusion because they are bound by their respective sheaths. When damp-heat steams and roasts within the blood aspect, the muscle texture becomes lax, causing the pulse vessels to relax and become loose, allowing blood to leak out and mix with fluids. This mixture reflects on the skin and excretes through sweat, resulting in a yellowish hue. Therefore, the treatment method involves either inducing sweating or purging, necessarily employing bitter-cold herbs to clear heat and dry dampness, assisted by blood-invigorating agents, to capture and vent the damp-heat in the blood aspect. Once the damp-heat is eliminated, the pulse vessels regain firmness, blood returns to its proper channels, and clear and turbid substances separate. Yin jaundice occurs due to internal cold in the constitution; deficient yang floats outward and stagnates, battling with dampness between muscles and interstices, still manifesting as damp-heat, rather than cold directly causing jaundice. In Yang jaundice with deep and rich color, excessive heat steams and corrupts body fluids, transforming them into yellow, viscous juices that reflect against blood, hence the deep color; in Yin jaundice with pale and dull color, rootless heat cannot steam and corrupt body fluids into viscosity, resulting in more water than blood, hence the pale color. Blood leaks sideways because it has been stagnant and coagulated by dampness, obstructing forward movement, while qi is forced by heat to squeeze laterally with strength, compounded by lax muscle texture, leading to lateral leakage of blood. Jaundice caused by retained blood follows this same principle. The *Neijing* states that dan disease develops into xiaozhong (polyphagia), which is due to damp-heat stagnating for a long time and transforming into dry fire; conversely, xiaozhong can also develop into dan disease. After dry fire is subdued by cooling, moistening, and clearing agents, its momentum is reduced but the root remains; residual flames burn internally, transforming back into damp-heat.
Hei Dan (Black Jaundice) develops from prolonged Nü Lao Dan (Jaundice due to sexual exhaustion), Gu Dan (Grain Jaundice), and Jiu Dan (Alcohol Jaundice). It is caused by Kidney deficiency with dryness and Spleen damp-heat. The Kidney dislikes dryness, and the Spleen dislikes dampness. When the Kidney is dry, it urgently needs water essence from other organs to moisten it. At this time, if there is excess Spleen dampness, it directly absorbs it, inadvertently absorbing the toxic damp-heat as well. Turbid qi from the Spleen and Kidney overflows into the meridians, disturbing the new essences derived from daily diet, preventing clear qi from nourishing, so that blood vessels throughout the body cannot eliminate the old and absorb the new, resulting in a dark black hue. A slight distinction should be made: If Kidney water is not severely deficient, but the Spleen and Stomach are self-deficient, with turbid qi flowing downward, the disease is in the Middle Jiao and is easy to treat. If the complexion is black and floating/moist, indicating severe Kidney water deficiency where absorbed Spleen turbidity penetrates deeply like oil into flour, the disease is in the Lower Jiao, with a black and stagnant complexion. For treating the Middle Jiao, clear the Stomach and soothe the Liver, nourish the Kidney and promote urination, using formulas such as Xiaochaihu Tang (Minor Bupleurum Decoction) or Yinchin Wuling San (Artemisia Capillaris and Five-Ingredient Poria Pill); for Yin jaundice, use Lizhong Tang (Regulate the Middle Decoction) variants containing Huanglian (Coptis Rhizome) and Zhishi (Immature Bitter Orange). For treating the Lower Jiao, nourish the Kidney and tonify the Lung; do not clear the Stomach or promote urination initially. Use Zishen Wan (Kidney-Nourishing Pill) or Dabu Yin Wan (Great Yin-Supplementing Pill) with Renshen (Ginseng Root). Only after Lung qi is sufficient and Kidney yin is restored should one proceed to clear the Stomach and promote urination; for Yin jaundice, use Yinchin Sini Tang (Artemisia Capillaris and Counterflow Decoction). Generally, one must combine one or two blood-transforming herbs, such as Taoren (Peach Seed), Honghua (Carthamus Flower), Qiancao (Madder Root), or Danshen (Salvia Miltiorrhiza Root). Since damaged blood cannot restore its original quality, it must be transformed so as not to hinder the circulation of new blood.