太阳病。项背强。KT KT 。无汗。恶风。葛根汤主之。
太阳病。项背强。KT KT 。汗出。恶风者。中风表虚也。项背强。KT KT 。无汗。恶风
者。中风表实也。表虚宜解肌。表实宜发汗。是以葛根汤发之也。
葛根（四两） 麻黄（三两去节） 桂枝（二两去皮） 芍药（二两切） 甘草（二
两炙） 生姜（三两切） 大枣（十二枚擘）
上七味。 咀。以水一斗。先煮黄葛根。减二升。去沫。内诸药。煮取三升。去滓。
温服一升。覆、取微似汗。不须啜粥。余如桂枝法将息及禁忌。
本草云。轻可去实。麻黄葛根之属是也。此以中风表实。故加二物于桂枝汤中也。
张卿子云。按前桂枝葛根汤。则此葛根汤上。似失麻黄二字。盖二葛根。即桂枝麻
黄变例也。故二证项背强KT KT 、恶风、一也。
太阳与阳明合病者。必自下利。葛根汤主之。
伤寒有合病。有并病。本太阳病不解。并于阳明者。谓之并病。二经俱受邪。相合
病者。谓之合病。合病者。邪气甚也。太阳阳明合病者。与太阳少阳合病。阳明少阳合
病。皆言必自下利者。以邪气并于阴。则阴实而阳虚。邪气并于阳。则阳实而阴虚。寒
邪气甚。客于二阳。二阳方外实而不主里。则里气虚。故必下利。与葛根汤。以散经中甚
邪。
太阳与阳明合病。不下利。但呕者。葛根加半夏汤主之。
邪气外甚。阳不主里。里气不和。气下而不上者。但下利而不呕。里气上逆而不下
者。但呕而不下利。与葛根汤以散其邪。加半夏。以下逆气。
Taiyang disease (Disease of the Taiyang channel). Stiffness and tension in the neck and back, KT KT , absence of sweating, aversion to wind. Gegen Tang (Kudzu Decoction) is indicated.
Taiyang disease (Disease of the Taiyang channel). Stiffness and tension in the neck and back, KT KT , presence of sweating, aversion to wind: this is Wind-strike with Exterior Deficiency (Zhongfeng Biaoxu). Stiffness and tension in the neck and back, KT KT , absence of sweating, aversion to wind: this is Wind-strike with Exterior Excess (Zhongfeng Biaoshi). For Exterior Deficiency, resolving the muscle layer (Jieji) is appropriate; for Exterior Excess, inducing sweating (Fahan) is appropriate. Therefore, Gegen Tang (Kudzu Decoction) is used to disperse the pathogen.
Gegen (Puerariae Radix, Kudzu Root) - 4 liang
Mahuang (Ephedrae Herba, Ephedra) - 3 liang, remove joints
Guizhi (Cinnamomi Ramulus, Cinnamon Twig) - 2 liang, remove bark
Shaoyao (Paeoniae Radix Alba, White Peony Root) - 2 liang, sliced
Gancao (Glycyrrhizae Radix et Rhizoma, Licorice Root) - 2 liang, honey-fried
Shengjiang (Zingiberis Rhizoma Recens, Fresh Ginger) - 3 liang, sliced
Dazao (Ziziphi Jujubae Fructus, Jujube) - 12 pieces, split
The above seven ingredients are coarsely crushed. Add ten dou of water, first decoct Gegen (Puerariae Radix, Kudzu Root), reduce by two dou, skim off the foam, then add the remaining herbs. Decoct until three sheng remain, strain the dregs. Take one sheng warm. Cover the patient to induce a slight sweat. There is no need to drink hot porridge afterwards. Other nursing instructions and dietary restrictions follow those of Guizhi Tang (Cinnamon Twig Decoction).
Bencao (Compendium of Materia Medica) states: "Light substances can dispel excess." Mahuang (Ephedrae Herba, Ephedra) and Gegen (Puerariae Radix, Kudzu Root) belong to this category. Here, because it is Wind-strike with Exterior Excess, these two substances are added to Guizhi Tang (Cinnamon Twig Decoction).
Zhang Qingzi said: Referring to the previous Guizhi Jia Gegen Tang (Cinnamon Twig Decoction plus Kudzu Root), it seems that the character 'Mahuang' (Ephedra) is missing from the name of this Gegen Tang (Kudzu Decoction). These two Gegen formulas are variations of Guizhi Tang (Cinnamon Twig Decoction) and Mahuang Tang (Ephedra Decoction). Thus, both syndromes present with stiffness and tension in the neck and back, KT KT , and aversion to wind.
When Taiyang (Taiyang Channel) and Yangming (Yangming Channel) diseases occur simultaneously (Hebing, Combined Disease), spontaneous diarrhea will inevitably occur. Gegen Tang (Kudzu Decoction) is indicated.
In Shanghan (Cold Damage) diseases, there are Hebing (Combined Disease) and Bingbing (Consecutive Disease). If the original Taiyang disease does not resolve and the pathogen moves into the Yangming channel, it is called Bingbing (Consecutive Disease). If both channels are affected by pathogens simultaneously and manifest together, it is called Hebing (Combined Disease). Hebing indicates severe pathogenic factors. In cases of Taiyang-Yangming Hebing, as well as Taiyang-Shaoyang Hebing and Yangming-Shaoyang Hebing, spontaneous diarrhea is mentioned because when pathogens merge into Yin, Yin becomes excessive and Yang deficient; when pathogens merge into Yang, Yang becomes excessive and Yin deficient. When cold pathogenic factors are severe and lodge in two Yang channels, these Yang channels are externally full but cannot govern the interior, leading to interior Qi deficiency. Hence, spontaneous diarrhea occurs. Gegen Tang (Kudzu Decoction) is given to disperse the severe pathogens within the channels.
When Taiyang (Taiyang Channel) and Yangming (Yangming Channel) diseases occur simultaneously, without diarrhea but with vomiting only, Gegen Jia Banxia Tang (Kudzu Decoction plus Pinellia) is indicated.
When pathogens are severe on the exterior, Yang cannot govern the interior, and interior Qi is disharmonious. If Qi descends instead of ascending, there is only diarrhea without vomiting. If interior Qi rebels upward instead of descending, there is only vomiting without diarrhea. Gegen Tang (Kudzu Decoction) is given to disperse the pathogen, and Banxia (Pinelliae Rhizoma, Pinellia Tuber) is added to direct rebellious Qi downward.