治中风伤寒，太阳病头项强痛，发热恶风恶寒，鼻鸣干呕，脉浮弱，汗自出者；杂病自
汗盗汗，虚疟虚痢，皆可治之。若脉浮紧而无汗者，不可用；酒客及亡血家，虽病风寒而汗
出者，亦忌之。
桂枝（去皮） 芍药（各三两） 甘草（二两炙） 生姜（三两） 大枣（十二枚擘） 水
七升，微火
桂枝汤方是解肌，（《伤寒论·太阳篇》云“桂枝本为解肌”，明非发汗也。）芍药甘草姜
枣维。啜粥渍形充胃气，（桂枝本不能发汗，故须助以热粥，充胃气以达于肺，肺主皮毛，
汗所从出，是渍形为汗也。观于此，可知伤寒不禁食矣。）调和营卫汗斯滋。（此方桂、芍相
须，姜、枣相得，是调和营卫之方。营卫和则汗自出，故曰“解肌”。）中风伤寒太阳病，虚
疟（调和营卫之功）虚痢（和阳敛阴之效）悉治之。大凡发热脉浮弱，恶寒汗出最相宜。（桂
枝一味，治太阳发热恶寒之的药。因脉浮弱汗自出，故加白芍敛阴护营，生姜佐桂以解表，
大枣佐芍以和里，更用甘草和诸药。凡发热恶寒，脉浮弱，汗自出者，合此证即用此汤，勿
拘风寒杂证也。）若然无汗脉浮紧，（是麻黄证）酒客血家切忌施。（无汗忌酸敛，酒客忌甘，
血家忌辛热，故皆不可用。）夏月黄芩加入剂，改名阳旦汤宜知。（夏月用桂枝汤加黄芩，名
阳旦汤。）
Indicated for Wind-stroke or Cold damage causing Taiyang disease (Taiyang Disease), characterized by stiffness and pain in the head and neck, fever, aversion to wind and cold, nasal congestion with roaring sound, dry retching, floating and weak pulse, and spontaneous sweating; also applicable to miscellaneous diseases involving spontaneous sweating, night sweats, deficiency-type malaria, and deficiency-type dysentery. It is contraindicated if the pulse is floating and tight without sweating; it should also be avoided in habitual drinkers and those with a history of blood loss, even if they present with Wind-Cold symptoms and sweating.
Guizhi Tang (Cinnamon Twig Decoction): Guizhi (Cinnamomi Ramulus) 3 liang (peeled), Shaoyao (Paeoniae Radix Alba) 3 liang, Gancao (Glycyrrhizae Radix et Rhizoma) 2 liang (roasted), Shengjiang (Zingiberis Rhizoma Recens) 3 liang, Dazao (Jujubae Fructus) 12 pieces (split). Decoct with 7 sheng of water using mild heat.
The function of Guizhi Tang (Cinnamon Twig Decoction) is to resolve the muscle layer (Jie Ji). As stated in *Shanghan Lun · Taiyang Chapter*, "Guizhi is primarily for resolving the muscle layer," clearly indicating it is not a diaphoretic (sweating-inducing) agent. The formula combines Shaoyao (Paeoniae Radix Alba), Gancao (Glycyrrhizae Radix et Rhizoma), Shengjiang (Zingiberis Rhizoma Recens), and Dazao (Jujubae Fructus) with Guizhi (Cinnamomi Ramulus). After taking the medicine, drink hot porridge to warm the body and replenish Stomach Qi (Wei Qi). (Guizhi (Cinnamomi Ramulus) alone cannot induce sweating; thus, hot porridge is needed to assist by replenishing Stomach Qi and transmitting it to the Lung, which governs the skin and hair. Sweat emerges from here, meaning the body is moistened to produce sweat. From this, we understand that patients with Cold damage are not prohibited from eating.) This formula harmonizes Ying (Nutritive Qi) and Wei (Defensive Qi), allowing sweat to emerge moderately. (In this formula, Guizhi (Cinnamomi Ramulus) and Shaoyao (Paeoniae Radix Alba) work synergistically, while Shengjiang (Zingiberis Rhizoma Recens) and Dazao (Jujubae Fructus) complement each other, making it a formula for harmonizing Ying (Nutritive Qi) and Wei (Defensive Qi). When Ying (Nutritive Qi) and Wei (Defensive Qi) are harmonized, sweat occurs normally, hence it is called "resolving the muscle layer".) It treats Taiyang disease caused by Wind-stroke or Cold damage, as well as deficiency-type malaria (relying on the effect of harmonizing Ying [Nutritive Qi] and Wei [Defensive Qi]) and deficiency-type dysentery (relying on the effect of harmonizing Yang and astringing Yin). Generally, for symptoms of fever, floating and weak pulse, aversion to cold, and sweating, this formula is most suitable. (Guizhi (Cinnamomi Ramulus) alone is a herb for treating Taiyang fever and aversion to cold. Because the pulse is floating and weak with spontaneous sweating, Baishao (Paeoniae Radix Alba) is added to astringe Yin and protect Ying (Nutritive Qi); Shengjiang (Zingiberis Rhizoma Recens) assists Guizhi (Cinnamomi Ramulus) to release the exterior; Dazao (Jujubae Fructus) assists Shaoyao (Paeoniae Radix Alba) to harmonize the interior; and Gancao (Glycyrrhizae Radix et Rhizoma) harmonizes all herbs. Whenever there is fever, aversion to cold, floating and weak pulse, and spontaneous sweating, this decoction should be used regardless of whether it is Wind-Cold or a miscellaneous disease.) However, if there is no sweating and the pulse is floating and tight, (this indicates Mahuang Tang (Ephedra Decoction) syndrome), it is strictly contraindicated for habitual drinkers and those with blood loss. (Astringent herbs are contraindicated for those without sweating; sweet herbs are contraindicated for habitual drinkers; acrid-hot herbs are contraindicated for those with blood loss, so these groups should not use this formula.) In summer, Huangqin (Scutellariae Radix) can be added to the prescription, renamed Yangdan Tang (Yangdan Decoction), which should be known.