甘草（二两） 干姜（两半） 附子（一枚）
煎成凉服。
太阴自利不渴，阴证脉沉身痛，与夫厥逆下利，脉不至者，此方皆主之。
论曰∶自利不渴属太阴。太阴主水谷，病故自利；内有真寒，故不渴。阴证者，举三阴
而言，则又非独太阴矣。病在里，故脉沉。寒则血脉凝涩，故身痛。四肢受气于里，里寒则
阳
寒淫于内，治以甘热。故用甘草、姜、附大热之剂；申发阳气，祛散阴寒，能温经暖肌而回
四逆，因以名汤焉。然必凉服者，经曰治寒以热，凉而行之是也。否则戴阳者，反增上燥，
耳目口鼻皆血者有矣。药之难用也有如此。
干姜（炮） 黄连（炮） 黄芩（炮） 人参（去芦，各三两）
伤寒误吐下，寒气内格，食入口即吐者，此方主之。
不当吐下而吐下之，故曰误吐下。如用栀子、瓜蒂之类以吐，又用承气之类以下，其性
皆寒，误用之，则损中气。中气既虚且寒，便恶谷气，故食入口即吐。入口即吐者，犹未下
咽之谓也。用干姜之辛热，所以散寒；用人参之甘温，所以补虚；复用芩、连之寒苦者，所
以假之从寒而通格也。经曰∶有假其气，则无禁也，正此之谓。自非深得经旨，故能通其变
耶？
当归（去土） 桂枝 芍药（炒，各三两） 细辛（去土） 甘草（炙） 通草（各二
两） 大枣
（廿五枚）
论曰∶伤寒脉滑而厥者，里有热也，白虎汤主之；手足厥寒，脉细欲绝者，当归四逆汤
主之。
滑，阳脉也。故其厥为阳厥，乃火极盛，如干之上九，亢龙有悔之象也，故用白虎。白
虎考见前。若手足厥寒，脉细欲绝，则非白虎所宜矣。手足厥寒，则阳气外虚，不温四末；
脉细欲绝，则阴血内弱，脉行不利。阳气外虚，故用桂枝、细辛以温其表；阴血内弱，故用
当归、芍药以调其里；通草通其阴阳；大枣、甘草和其营卫。是证也，自表入里，虽曰传至
厥阴，始终只是阳证，与寒邪直中三阴不同，故不用吴萸、姜、附辈，而用桂枝汤加当归、
细辛、通草尔。明者自得之。
甘草（二两） 干姜（一两半） 附子（一枚）
煎煮成药液后，待冷却服用。
太阴病出现的自发性腹泻且不口渴，阴证表现为脉象沉、身体疼痛，以及四肢厥冷伴下利、脉搏摸不到的情况，此方均主治。
论述说：自发性腹泻且不口渴属于太阴病。太阴主管水谷运化，患病故出现自发性腹泻；体内有真寒，所以不口渴。所谓阴证，是泛指三阴经而言，则不仅仅是太阴了。病位在里，所以脉象沉。寒邪导致血脉凝滞涩阻，所以身体疼痛。四肢的气血来源于内脏，内脏寒冷则阳气受抑。寒邪淫盛于内，治疗应用甘热之品。因此使用甘草、干姜、附子等大热药物；以申发阳气，驱散阴寒，能够温通经脉、温暖肌肉而挽回四肢厥逆，因此将此汤命名为四逆汤。然而必须凉服的原因，正如经典所说：治疗寒证用热药，但要凉着服用。否则对于戴阳证（虚阳上浮），反而会增加上部的燥热，导致耳目口鼻出血的情况发生。药物的运用难度如此之大。
干姜（炮制） 黄连（炮制） 黄芩（炮制） 人参（去芦头，各三两）
伤寒误用催吐或泻下法，寒气内结格拒，食物入口即吐出的情况，此方主治。
本不应使用吐下法却使用了，所以称为误吐下。如使用栀子、瓜蒂之类来催吐，又使用承气汤之类来泻下，这些药物性质皆寒，误用之后，会损伤中焦之气。中气既虚弱又寒冷，便厌恶谷气，所以食物入口即吐出。所谓“入口即吐”，是指食物尚未咽下的意思。使用干姜的辛热之性，是为了散寒；使用人参的甘温之性，是为了补虚；再复用黄芩、黄连的寒苦之性，是为了假借其寒性以顺应病势从而开通格拒。经典说：假借药物的气味（指反佐），就没有禁忌了，正是这个意思。如果不是深得经典旨意，怎能通达这种变化呢？
当归（去泥土） 桂枝 芍药（炒，各三两） 细辛（去泥土） 甘草（炙） 通草（各二两） 大枣（二十五枚）
论述说：伤寒脉象滑数且四肢厥冷的，是里有热，用白虎汤主治；手足厥冷，脉象细微几乎要断绝的，用当归四逆汤主治。
滑脉，是阳脉。所以其厥冷为阳厥，乃是火极盛的表现，如同《易经》乾卦上九爻辞“亢龙有悔”的意象，所以用白虎汤。白虎汤考见前文。如果手足厥冷，脉象细微欲绝，则不是白虎汤所适宜的。手足厥冷，说明阳气在外虚弱，不能温煦四肢末端；脉象细微欲绝，说明阴血在内虚弱，脉道运行不利。阳气在外虚弱，所以用桂枝、细辛来温煦体表；阴血在内虚弱，所以用当归、芍药来调和内部；通草通行阴阳；大枣、甘草调和营卫。此证候，由表入里，虽然说是传变至厥阴经，但始终只是阳证，与寒邪直接中伤三阴经不同，所以不用吴茱萸、干姜、附子这类药物，而使用桂枝汤加入当归、细辛、通草。明眼人自然能明白其中的道理。
Gancao (Radix Glycyrrhizae Preparata, 2 liang), Ganjiang (Rhizoma Zingiberis Preparata, 1.5 liang), Fuzi (Radix Aconiti Lateralis Preparata, 1 piece).
Decoct and take the medicine when it has cooled down.
This formula is indicated for spontaneous diarrhea without thirst in Taiyin disease (disease of the Spleen/Stomach channel characterized by deficiency-cold), Yin syndrome (syndrome characterized by deficiency-cold) presenting with a deep pulse and body pain, as well as cold extremities with diarrhea and an imperceptible pulse.
The discussion states: Spontaneous diarrhea without thirst belongs to Taiyin. Taiyin governs the transformation and transportation of water and grain; thus, illness leads to spontaneous diarrhea. The presence of true cold inside causes the lack of thirst. "Yin syndrome" refers generally to the three Yin channels, implying it is not limited to Taiyin alone. Since the pathology is in the interior, the pulse is deep. Cold causes blood vessels to coagulate and become stagnant, resulting in body pain. The four limbs receive Qi from the interior; interior cold suppresses Yang. When cold pathogen dominates internally, treatment should employ sweet and hot agents. Therefore, Gancao, Ganjiang, and Fuzi, which are strongly hot, are used to promote Yang Qi and dispel Yin cold, thereby warming the meridians and muscles to reverse cold extremities. Hence, the decoction is named Si Ni Tang (Four Extremities Reversal Decoction). However, it must be taken cool because the classics state: "Treat cold with heat, but administer it cool." Otherwise, in cases of Dai Yang syndrome (floating false Yang), using hot medicine hotly would exacerbate upper dryness, potentially leading to bleeding from the eyes, ears, mouth, and nose. The difficulty in applying medicinal substances is such.
Ganjiang (Rhizoma Zingiberis Preparata, processed), Huanglian (Rhizoma Coptidis Preparata, processed), Huangqin (Radix Scutellariae Preparata, processed), Renshen (Radix Ginseng Preparata, de-rhizome, each 3 liang).
This formula treats conditions where, after erroneous emesis or purgation in Shanghan (Cold Damage), cold pathogen becomes obstructed internally, causing food to be vomited immediately upon entering the mouth.
Emesis and purgation were inappropriate yet applied, hence termed "erroneous emesis and purgation." For instance, using Zhi Zi (Fructus Gardeniae) or Gua Di (Semen Coicis/other emetics) for emesis, and Cheng Qi Tang (Harmonizing the Qi Decoctions) for purgation, these agents are inherently cold. Erroneous use damages Middle Qi (Spleen/Stomach Qi). With Middle Qi both deficient and cold, there is aversion to grain Qi, causing immediate vomiting upon ingestion. "Immediate vomiting upon entry" means the food has not even been swallowed. Ganjiang's pungent-hot nature disperses cold; Renshen's sweet-warm nature tonifies deficiency; additionally, Huangqin and Huanglian's cold-bitter nature is employed to borrow their cold quality to facilitate passage through the obstruction (Ge Ju). The classics say: "If one borrows the Qi (nature/flavor), there are no prohibitions," which precisely refers to this principle. Unless one deeply comprehends the essence of the classics, how could one master such variations?
Danggui (Radix Angelicae Sinensis, cleaned), Guizhi (Ramulus Cinnamomi), Shaoyao (Radix Paeoniae Alba, stir-fried, each 3 liang), Xixin (Herba Asari, cleaned), Gancao (Radix Glycyrrhizae Preparata, honey-fried), Tongcao (Medulla Tetrapanacis, each 2 liang), Dazao (Fructus Jujubae, 25 pieces).
The discussion states: In Shanghan, if the pulse is slippery and there are cold extremities, it indicates heat within the interior, treated with Baihu Tang (White Tiger Decoction); if hands and feet are cold with a fine pulse nearly absent, it is treated with Danggui Sini Tang (Angelica Four Extremities Reversal Decoction).
A slippery pulse is a Yang pulse. Thus, the cold extremities constitute Yang Jue (Yang reversal/cold extremities due to excess heat), representing extreme fire intensity, analogous to the image of "Arrogant Dragon will have cause to repent" in the top nine line of the Qian Hexagram in the I Ching; therefore, Baihu Tang is used. See previous text for Baihu Tang analysis. If hands and feet are cold with a fine pulse nearly absent, Baihu Tang is not suitable. Cold extremities indicate exterior Yang deficiency, failing to warm the four extremities; a fine pulse nearly absent indicates interior Yin-blood deficiency, impeding pulse flow. Due to exterior Yang deficiency, Guizhi and Xixin are used to warm the exterior; due to interior Yin-blood deficiency, Danggui and Shaoyao are used to regulate the interior; Tongchai unites Yin and Yang; Dazao and Gancao harmonize Ying (Nutritive) and Wei (Defensive) Qi. This syndrome progresses from exterior to interior; although it is said to transmit to the Jueyin channel, it remains fundamentally a Yang syndrome, distinct from direct invasion of the Three Yin channels by cold pathogen. Therefore, Wuzhuyu (Fructus Evodiae), Ganjiang, and Fuzi are not used, but rather Guizhi Tang (Cinnamon Twig Decoction) added with Danggui, Xixin, and Tongcai. Those who are clear will understand this naturally.