发黄胆是腑病，非经病也。疫邪传里，遗热下焦，小便不利，邪无输泄，经气郁
滞，其传为疸，身目如金者，宜茵陈汤。
茵陈汤
茵陈（一钱） 山栀（二钱） 大黄（五钱）
水姜煎服。
按∶茵陈为治疸退黄之专药，今以病证较之，黄因小便不利，故用山栀除小肠屈曲之火，瘀
热既除，小便自利。当以发黄为标，小便不利为本。及论小便不利，病原不在膀胱，乃系胃
家移热，又当以小便不利为标，胃实为本。是以大黄为专功，山栀次之，茵陈又其次也。设去
大黄而服山栀、茵陈，是忘本治标，鲜有效矣。或用茵陈五苓，不惟不能退黄，小便间亦难
利。
愚按∶旧论发黄，有从湿热，有从阴寒者，阴病发黄确有其证，何得云妄？湿热发黄尤为最多，大约如合曲相似。
饮入于胃，胃气薰蒸则成湿热。湿热外蒸，透入肌腠遂成黄病。燥火焉有发黄之理？此言为吴君白圭之玷。
温疫胸膈满闷，心烦喜呕，欲吐不吐，虽吐而不得大吐，腹不满，欲饮不能饮，
欲食不能食，此疫邪留于胸膈，宜瓜蒂散吐之。
瓜蒂散
甜瓜蒂（一钱） 赤小豆（二钱，研碎） 生山栀仁（二钱）
上用水二钟，煎一钟，后入赤豆，煎至八分，先服四分，一时后不吐，再服尽。吐之未
尽，烦满尚存者，再煎服。如无瓜蒂，以淡豆豉二钱代之。
发黄属于胆腑的病变，而不是经络的病变。疫邪传入体内深处，遗留热邪在下焦，导致小便不通畅，病邪没有排泄途径，经气郁结阻滞，进而转化为疸病，身体和眼睛都像金子一样发黄时，适宜使用茵陈汤。
茵陈汤
茵陈（一钱） 山栀（二钱） 大黄（五钱）
加水、生姜煎煮后服用。
按语：茵陈是治疗疸病、消退黄疸的专用药物。现在结合病情来看，黄疸是因为小便不利引起的，所以用山栀清除小肠屈曲部位的热火，瘀积的热邪既已清除，小便自然通畅。应当以发黄为标症，小便不利为本源。等到讨论小便不利的病因时，病源并不在膀胱，而是源于胃家转移来的热邪，此时又应当以小便不利为标症，胃实（胃肠积滞）为本源。因此大黄发挥主要功效，山栀次之，茵陈再次之。如果去掉大黄而只服用山栀和茵陈，这是忘记本源而只治疗标症，很少能见效。或者使用茵陈五苓散，不仅不能消退黄疸，小便有时也难以通利。
我按语：旧有的理论认为发黄，有的源于湿热，有的源于阴寒。阴寒导致的发黄确实有其证候，怎么能说这种观点是荒谬的呢？湿热导致的发黄尤为多见，大致就像酒曲发酵相似。饮食进入胃中，胃气熏蒸则形成湿热。湿热向外蒸腾，透入肌肤腠理遂成黄病。燥火怎么会有发黄的道理呢？这种说法是吴君白圭的瑕疵。
温疫病出现胸膈部胀满憋闷，心烦意乱且喜欢呕吐，想吐却吐不出来，虽然呕吐但无法彻底吐出，腹部不胀满，想喝水却喝不下去，想吃东西却吃不下，这是疫邪停留在胸膈部位，适宜用瓜蒂散催吐。
瓜蒂散
甜瓜蒂（一钱） 赤小豆（二钱，研碎） 生山栀仁（二钱）
以上药材用水两钟（古代量器），煎煮成一钟，之后加入赤小豆，继续煎煮至八分满，先服用四分，过一小时后若未呕吐，再服完剩余的药液。如果催吐未尽，烦闷胀满的症状仍然存在，再煎药服用。如果没有瓜蒂，可以用淡豆豉二钱代替。
Jaundice (Huang Dan) is a disease of the fu organs (hollow organs), not of the jing meridians. When epidemic pathogens transmit inward, leaving heat in the lower jiao, urination becomes difficult. With no outlet for the pathogens, the qi of the meridians becomes stagnant and depressed, transforming into jaundice. When the body and eyes appear golden yellow, Yinchen Tang (Cinchona Decoction) is indicated.
Yinchen Tang (Cinchona Decoction)
Yin Chen Hao (Artemisiae Scopariae Herba, 1 qian)
Shan Zhi (Gardeniae Fructus, 2 qian)
Da Huang (Rhei Radix et Rhizoma, 5 qian)
Decoct with water and fresh ginger; take orally.
Commentary: Yin Chen Hao is the specific herb for treating jaundice and resolving yellowness. Comparing this with the clinical presentation, the jaundice arises from difficulty in urination; therefore, Shan Zhi is used to clear the fire in the convoluted part of the small intestine. Once the stasis-heat is cleared, urination naturally becomes smooth. The yellowing should be regarded as the branch manifestation (symptom), while the difficulty in urination is the root cause. Regarding the etiology of difficult urination, the source is not in the bladder but rather heat transferred from the stomach/intestines. In this context, the difficulty in urination is the branch, and gastric excess (stomach fullness/accumulation) is the root. Thus, Da Huang performs the primary function, Shan Zhi is secondary, and Yin Chen Hao is tertiary. If Da Huang is omitted and only Shan Zhi and Yin Chen Hao are taken, it means neglecting the root to treat the branch, which rarely yields efficacy. Alternatively, using Yinchen Wuling San (Yinchen Five-Ling Powder) will not only fail to resolve the jaundice but may also make urination difficult at times.
My Commentary: Old theories state that jaundice arises either from damp-heat or from yin-cold. There are indeed cases of jaundice caused by yin-disease; how can such views be dismissed as absurd? Jaundice due to damp-heat is particularly common, resembling the fermentation process of koji (malt). Food enters the stomach, and the steaming action of stomach qi generates damp-heat. As damp-heat steams outward and penetrates the muscle and interstices, jaundice forms. How could dry-fire cause jaundice? This statement is a flaw in Wu Jun Baigui's argument.
In warm epidemics, if there is chest and diaphragm fullness and oppression, mental restlessness, frequent desire to vomit, an urge to vomit without success, vomiting that does not fully expel the pathogen, abdominal distension is absent, thirst exists but drinking is impossible, and appetite is lost despite the desire to eat, this indicates epidemic pathogens lingering in the chest and diaphragm. Guadi San (Melon Seed Powder) should be used to induce vomiting.
Guadi San (Melon Seed Powder)
Tian Gua Di (Momordicae Semen, 1 qian)
Chi Xiao Dou (Vigna umbellatae Semen, 2 qian, ground)
Sheng Shan Zhi Ren (Gardeniae Semen, 2 qian)
Take two zhong of water, decoct until one zhong remains. Then add Chi Xiao Dou, decoct until eight-tenths remain. Take one-fourth first. If vomiting does not occur after one hour, consume the remainder. If vomiting is incomplete and mental restfulness and fullness persist, decoct and administer again. If Tian Gua Di is unavailable, substitute with Dan Dou Chi (Sojae Praeparatio, 2 qian).