芍药 白术 茯苓 生姜（各三两） 甘草（二两炙） 大枣（十二枚擘）
上六味。以水八升。煮取三升。去滓。温服一升。小便利则愈。
此治太阳里水法也。经云。服桂枝汤。或下之。仍头项强痛。翕翕发热。无汗。心下满
。微
痛。小便不利者。本方主之。按头项强痛。翕翕发热。明是桂枝汤证。乃服汤已。或下之。
而本证仍在。反加无汗。汗不外出。水气停于心下。因而满痛。但满而不硬。痛而尚微。又
非误下结胸之比。皆因小便不利。膀胱之水不行。致中焦之气不运。虽见太阳诸证。病恰在
府而不在经。病不在经。不当攻表。自宜去桂。病已入府。法当行水。宜加苓术培土制水。
而姜芍甘枣。乃得协成利水散邪之功。以其证本太阳。故虽去桂而仍以桂枝名汤也。
按此条。方中行谓中风兼寒。故桂枝及下法皆误。喻嘉言亦从其解。而程郊倩又以中气
虚津液少
立论。总觉牵强附会。与方义不甚相合。惟柯韵伯主太阳府病立论。王晋三亦以为治太阳里
水法。则理路乃觉清晰。而方义亦属熨贴。今从之。
桂枝（四两去皮） 甘草（四两炙） 白术（三两） 人参（三两） 干姜（三两）
上五味。以水九升。先煎四味。取五升。纳桂枝。更煮取三升。去滓。温服一升。日再
服。夜一服。
此理中加桂枝而易其名也。经云。太阳病。外证未除。而数下之。遂协热而利。利下不
止。
心下痞硬。表里不解者。此汤主之。盖因误下则里虚。里虚则热入。里虚不能内守。遂协同
外热。变而为利下不止。而必又心下痞硬。邪滞上焦。犹兼半表。故曰表里不解。夫下利不
止。何以不用四逆以救里。以表热未罢也。心下痞硬。何以不用泻心以清里。以里气已虚也
。此证辄防阳并入阴。故不但泻心中芩连不可用。即桂枝汤中芍药亦不可用。乃取桂枝行阳
于外以解表。理中助阳于内以止利。此表里两解之治法也。
Paeoniae Radix Alba (Shaoyao, 白芍), Atractylodis Macrocephalae Rhizoma (Baizhu, 白术), Poria (Fuling, 茯苓), Zingiberis Recens Rhizoma (Shengjiang, 生姜) [each 3 liang], Glycyrrhizae Radix et Rhizoma Preparata cum Melle (Gancao, 甘草) [2 liang, honey-fried], Ziziphi Jujubae Fructus (Dazao, 大枣) [12 pieces, split open].
The above six herbs. Use eight sheng of water. Decoct to obtain three sheng. Remove the dregs. Take one sheng warm. When urination becomes smooth, the disease will be cured.
This is the method for treating interior water in Taiyang (Greater Yang). The classic states: After taking Guizhi Tang (Cinnamon Twig Decoction), or after purgation, if there are still stiffness and pain in the head and neck, feverishness with a sensation of heat covering the body (Xi Xi Fa Re), absence of sweating, fullness in the epigastrium, slight pain, and difficulty in urination, this formula should be used. Note: Stiffness and pain in the head and neck, and feverishness with a sensation of heat covering the body, clearly indicate a Guizhi Tang (Cinnamon Twig Decoction) pattern. Since the original symptoms persist after taking the decoction or undergoing purgation, but anhidrosis appears additionally, preventing sweat from exiting, water qi stagnates in the epigastrium, causing fullness and pain. However, the fullness is not hard, and the pain is slight, distinguishing it from chest binding (Jie Xiong) caused by erroneous purgation. All these result from difficulty in urination; the water in the Bladder does not circulate, leading to impaired movement of Qi in the Middle Jiao. Although various Taiyang (Greater Yang) symptoms are present, the disease lies precisely in the Fu organs rather than the Jing meridians. Since the disease is not in the Jing meridians, attacking the exterior is inappropriate. Therefore, Gui Zhi (Cinnamon Twig) should be removed. As the disease has entered the Fu organs, the treatment method should promote diuresis. It is appropriate to add Fuling (Poria) and Baizhu (Atractylodis Macrocephalae Rhizoma) to strengthen Spleen Earth to control water. Meanwhile, Shengjiang (Zingiberis Recens Rhizoma), Shaoyao (Paeoniae Radix Alba), Gancao (Glycyrrhizae Radix et Rhizoma), and Dazao (Ziziphi Jujubae Fructus) can cooperate to achieve the effect of promoting diuresis and dispersing pathogens. Because the syndrome originates from Taiyang (Greater Yang), although Gui Zhi (Cinnamon Twig) is removed, the formula retains the name "Guizhi" (Cinnamon Twig).
Note regarding this clause: Fang Zhongxing argued that Wind-strike combined with Cold made both Guizhi Tang (Cinnamon Twig Decoction) and purgation erroneous. Yu Jiayan also followed his interpretation. Cheng Jiaoqian based his theory on deficiency of Middle Qi and scanty fluids. These views seem forced and inconsistent with the rationale of the formula. Only Ke Yunbo’s argument based on Taiyang (Greater Yang) Fu organ disease, and Wang Jin San’s view that it treats interior water in Taiyang (Greater Yang), make the logic clear and the formula rationale appropriate. We adopt their view now.
Gui Zhi (Cinnamon Twig) [4 liang, bark removed], Gancao (Glycyrrhizae Radix et Rhizoma) [4 liang, honey-fried], Baizhu (Atractylodis Macrocephalae Rhizoma) [3 liang], Renshen (Ginseng Radix) [3 liang], Ganjiang (Zingiberis Rhizoma) [3 liang].
The above five herbs. Use nine sheng of water. First decoct the first four herbs to obtain five sheng. Add Gui Zhi (Cinnamon Twig), and decoct further to obtain three sheng. Remove the dregs. Take one sheng warm. Twice daily. Once at night.
This is Lizhong Tang (Regulate the Middle Decoction) with added Gui Zhi (Cinnamon Twig), renamed accordingly. The classic states: In Taiyang (Greater Yang) disease, if the exterior syndrome persists and multiple purgations have been performed, leading to diarrhea accompanied by fever (Xie Re Er Li), continuous diarrhea, epigastric stuffiness and hardness, and unresolved exterior and interior conditions, this decoction should be used. Generally, erroneous purgation causes interior deficiency. Interior deficiency allows heat to enter. Due to interior deficiency failing to retain internally, heat combines with external heat, transforming into continuous diarrhea. Furthermore, epigastric stuffiness and hardness occur due to pathogenic stagnation in the Upper Jiao, involving half-exterior, hence described as unresolved exterior and interior. Why not use Sini Tang (Frigid Extremities Decoction) to rescue the interior when diarrhea is continuous? Because the exterior heat has not yet subsided. Why not use Xiexin Tang (Drain the Epigastrium Decoctions) to clear the interior when there is epigastric stuffiness and hardness? Because the interior Qi is already deficient. This syndrome often prevents Yang from merging into Yin. Therefore, not only Huangqin (Scutellariae Radix) and Huanglian (Coptidis Rhizoma) from Xiexin Tang (Drain the Epigastrium Decoctions) are contraindicated, but also Shaoyao (Paeoniae Radix Alba) from Guizhi Tang (Cinnamon Twig Decoction) is contraindicated. Instead, Gui Zhi (Cinnamon Twig) is taken to move Yang outward to resolve the exterior, while Lizhong Tang (Regulate the Middle Decoction) assists Yang inward to stop diarrhea. This is a treatment method for resolving both exterior and interior simultaneously.