太阳中风。阳浮而阴弱。阳浮者热自发。阴弱者汗自出。啬啬恶寒。淅淅恶风。翕翕发热。鼻
鸣干呕者。桂枝汤主之。
太阳中风者。阳受风气而未及乎阴也。故其脉阳浮而阴弱。阳浮者。不待闭郁而热自发。
阴弱者。不必攻发而汗自出。所以然者。风为阳邪而上行。卫为阳气而主外。以阳从阳。其气必浮
。故热自发。阳得风而自强。阴无邪而反弱。以弱从强。其气必馁。故汗自出。啬啬恶寒。淅淅
恶风者。肌腠疏缓。卫气不谐。虽无寒而若不能御。虽无风而常觉洒淅也。翕、越也。动也。盛
也。言其热时动而盛。不似伤寒之一热至极也。鼻鸣干呕。不特风气上壅。亦邪气暴加。里气上争
之象。是宜桂枝汤助正以逐邪。抑攘外以安内也。
桂枝汤方
桂枝（三两去皮） 甘草（二两炙） 芍药（三两） 生姜（三两切） 大枣（十二枚擘）
上五味 咀。以水七升。微火煮取三升。去滓。适寒温。服一升。服已须臾。啜热稀粥一升
余。以助药力。温覆令一时许。遍身 。微似有汗者益佳。不可令如水流漓病。必不除。若一
服汗出病瘥。停后服。不必尽剂。若不汗。重服。根据前法。又不汗。后服小促。半日许。令三服尽
。若病重者。一日一夜服。周时观之。服一剂尽。病证犹在者。更作服。若汗不出者。乃服至
二三剂。禁生冷、粘滑、肉面、五辛、酒酪、臭恶等物。
按风之为气。能动阳气而泄津液。所以发热汗自出。与伤寒之发热无汗不同。此方用桂枝
发散邪气。即以芍药摄养津气。炙甘草合桂枝之辛。足以攘外。合芍药之酸。足以安内。生姜、
大枣。甘辛相合。补益营卫。亦助正气去邪气之用也。盖以其汗出而邪不出。故不用麻黄之发表。
而以桂枝助阳以为表。以其表病而里无热。故不用石膏之清里。而用芍药敛阴以为里。此桂枝汤之
所以异于麻黄、大青龙也。服已须臾。啜稀粥一升余。所以助胃气。即所以助药力。盖药力必藉胃气以行也。
温覆令微汗。不使流漓如水者。所谓汗出少者为自和。汗出多者为太过也。一服汗出病瘥停后服
者。中病即止。不使过之以伤其正也。若不汗。后服小促。及服至二三剂者。期在必克。以汗出为
和而止也。仲景示人以法中之法如此。
太阳病。头痛发热。汗出恶风者。桂枝汤主之。
太阳受邪。无论中风伤寒。俱有头痛。俱有发热。但伤于寒。则表实无汗。伤于风。则表疏自
汗。是头痛发热者。伤寒所同。而汗出恶风者。中风所独也。中风必以风剂治之。云桂枝汤主之者。
见非他药所得而更者耳。
太阳病。外证未解。脉浮弱者。当以汗解。宜桂枝汤。
太阳外证。即头痛、发热、恶风寒之属。外证未解。宜从汗解。然必审其脉之强弱而施治。若
脉浮弱。则是中风阳浮阴弱之候。治宜桂枝汤。助正以逐邪。
太阳病。外证未解者。不可下也。下
之为逆。欲解外者。宜桂枝汤主之。
伤寒在表者宜汗。在里者宜下。此大法也。是以外证未解者不可下。下之是病在表而攻其里
也。故曰逆。本论云、本发汗而复下之。此为逆也。若先发汗。治不为逆。此之谓也。而欲解外。
则桂枝成法。不可易矣。仲景于当汗之证。随示不可下之戒如此。
病常自汗出者。此为营气和。营气和者外不谐。以卫气不共营气和谐故耳。以营行脉中。卫行脉
外。复发其汗。营卫和则愈。宜桂枝汤。
此即前条阴弱者汗自出之意而发明之。谓营未病而和。则汗液自通。卫中风而不谐。则阴气
失护。宜其汗常自出也。夫营与卫。常相和谐者也。营行脉中。为卫之守。卫行脉外。为营之护。
何有发热恶寒之证哉。惟卫得风而自强。营无邪而反弱。邪正不同。强弱异等。虽欲和谐。不可
得矣。故曰营气和者外不
谐。不谐则岂特卫病而已哉。故欲营之安。必和其卫。欲卫之和。必逐其风。是宜桂枝汤助阳取汗。汗出
则邪去而卫和。卫和则营不受扰而愈。
病患脏无他病。时发热。自汗出。而不愈者。此卫气不和也。先其时发汗则愈。宜桂枝汤主
之。
人之一身。经络纲维于外。脏腑传化于中。而其为病。从外之内者有之。从内之外者有之。
脏无他病。里无病也。时发热自汗。则有时不发热无汗可知。而不愈者。是其病不在里而在表。
不在营而在卫矣。先其时发汗则愈者。于不热无汗之时。而先用药取汗。则邪去卫和而愈。不然。
汗液方泄而复发之。宁无如水淋漓之患耶。
太阳病。发热汗出者。此为营弱卫强。故使汗出。欲救邪风者。宜桂枝汤。
此即前条卫不谐营自和之意。而申其说。救邪风者。救卫气之为风邪所扰也。然仲景营弱
卫强之说。不过发明所以发热汗出之故。后人不察。遂有风并于卫。卫实而营虚。寒中于营。营实而卫虚之说。不
知邪气之来自皮毛而入肌肉。无论中风伤寒，未有不及于卫者。其甚者。乃并伤于营耳。郭白云
所谓涉卫中营者是也。是以寒之浅者。仅伤于卫。风而甚者。并及于营。卫之实者。风亦难泄。
卫而虚者。寒犹不固。无汗必发其汗。麻黄汤所以去表实而发邪气。有汗不可更发汗。桂枝汤所
以助表气而逐邪气。学人但当分病证之有汗无汗。以严麻黄桂枝之辨。不必执营卫之孰虚孰实。以证伤寒中风之殊。
且无汗为表实。何云卫虚。麻黄之去实。宁独遗卫。能不胶于俗说者。斯为豪杰之士。
太阳中风证。脉象阳部浮而阴部弱。阳浮表示热气自然散发，阴弱表示汗液自然流出。患者表现为怕冷畏缩、怕风瑟瑟、发热轻微且持续，伴有鼻鸣和干呕症状的，用桂枝汤主治。
太阳中风证，是阳气受风气侵袭而未波及阴气。所以其脉象阳浮而阴弱。阳浮，意味着不需要闭郁就会自然发热；阴弱，意味着不需要攻发就会自然出汗。之所以这样，是因为风为阳邪且向上行走，卫气属阳气且主司体表。以阳（风邪）从阳（卫气），其气必然浮越，所以热自发。阳气得风邪相助而自强，阴气无邪气干扰反而显得虚弱。以弱从强，其气必然衰馁，所以汗自出。啬啬恶寒、淅淅恶风，是因为肌腠疏缓，卫气不协调。虽然没有真正的寒气，却感觉不能抵御；虽然没有真正的风，却常觉得洒淅寒冷。翕，意为越动、动、盛。指热度时而动而旺盛，不像伤寒那样热势达到极致。鼻鸣和干呕，不仅是风气上壅塞，也是邪气突然加重，里气向上抗争的表现。此时适宜用桂枝汤扶助正气以驱逐邪气，抑止外邪以安顿内里。
桂枝汤方
桂枝（三两去皮） 甘草（二两炙） 芍药（三两） 生姜（三两切） 大枣（十二枚擘）
以上五味药，切碎。用水七升，用微火煮取三升。去渣滓。待温度适宜时，服用一升。服药后不久，喝热稀粥一升多，以助药力。覆盖衣被约一顿饭工夫，使全身微微似有汗出为最佳。不可让汗出如水流漓，否则病必不除。如果服一次药后汗出病愈，停服后面的药，不必服完所有药剂。如果没出汗，再次服药。按照前面的方法，如果仍不出汗，缩短后两次服药的时间间隔，半天左右让三次药服完。如果病情重的，一天一夜服药，观察二十四小时。服完一剂药后，病证仍在的，再制作服用。如果不出汗，就服药至二三剂。禁忌生冷、粘滑、肉类、面食、五辛、酒酪、臭恶等食物。
按语：风这种气，能扰动阳气而泄津液，所以发热汗自出，这与伤寒的发热无汗不同。此方用桂枝发散邪气，同时用芍药摄养津气。炙甘草配合桂枝的辛味，足以攘除外邪；配合芍药的酸味，足以安顿内里。生姜、大枣，甘辛相合，补益营卫，也是借助正气去除邪气的作用。因为已经出汗但邪气未出，所以不用麻黄来发表；因为表有病而里没有热，所以不用石膏来清里，而用芍药收敛阴气以为治里。这就是桂枝汤与麻黄汤、大青龙汤不同的原因。服药后不久，喝稀粥一升多，是为了助胃气，也就是助药力。因为药力必须依靠胃气才能运行。覆盖衣被令其微汗，不让汗出如水流漓，这就是所谓“汗出少者为自和，汗出多者为太过”。服一次药后汗出病愈就停服后面的药，这是中病即止，不让过剂伤害正气。如果不出汗，后两次服药时间稍缩短，以及服药至二三剂，目的是务必攻克病邪，以汗出作为痊愈的标志而停止。张仲景以此示人法中之法。
太阳病，出现头痛、发热、汗出、恶风症状的，用桂枝汤主治。
太阳经受邪，无论是中风还是伤寒，都有头痛，都有发热。但伤于寒，则表实无汗；伤于风，则表疏自汗。所以头痛发热是伤寒和中风共同的，而汗出恶风是中风的独有特征。中风必须用治风的方剂治疗。说“桂枝汤主之”，意思是除了它没有别的药可以替代。
太阳病，外证未解，脉象浮弱的，应当用发汗法解除，适宜用桂枝汤。
太阳外证，即头痛、发热、恶风寒之类。外证未解，宜从汗解。但必须审察脉象的强弱来施治。如果脉浮弱，那就是中风阳浮阴弱的证候，治疗适宜用桂枝汤，扶助正气以驱逐邪气。
太阳病，外证未解的，不可用下法。用下法是逆治。想要解除表证的，适宜用桂枝汤主治。
伤寒在表的宜用汗法，在里的宜用下法，这是大法。所以外证未解的不可用下法。用下法是病在表却攻其里，所以说这是逆治。本论说：“本应发汗却反而用下法，此为逆治。如果先发汗，治疗就不为逆。”说的就是这个道理。而要解除表证，桂枝汤是成法，不可改变。张仲景对于应当发汗的证候，如此警示不可用下法。
病人经常自汗出的，这是营气调和。营气调和说明外部不协调，是因为卫气不与营气和谐所致。因为营行于脉中，卫行于脉外。再次发其汗，营卫和谐就好了，适宜用桂枝汤。
这即是前条“阴弱者汗自出”的意思加以阐发。谓营气未病而调和，则汗液自然通畅；卫气受风邪干扰而不协调，则阴气失去保护，理应汗常自出。营与卫，本是常相和谐的。营行脉中，为卫的守备；卫行脉外，为营的护卫。怎么会有发热恶寒的证候呢？只是卫气得风邪而自强，营气无邪气干扰反而显得虚弱。邪正不同，强弱异等，虽然想和谐，也不可能了。所以说“营气和者外不谐”。不协调则岂止是卫气有病呢？所以要想营气安宁，必须调和卫气；要想卫气和谐，必须驱逐风邪。适宜用桂枝汤助阳取汗，汗出则邪去而卫和，卫和则营不受扰而痊愈。
病患内脏没有其他疾病，时常发热、自汗出，而不能痊愈的，这是卫气不和。在其发作之前发汗则痊愈，适宜用桂枝汤主治。
人的身体，经络纲维于外，脏腑传化于中。而其发病，有从外入内的，有从内出外的。内脏没有其他疾病，说明里无病。时常发热自汗，则可知有时不发热无汗。而不能痊愈，说明病不在里而在表，不在营而在卫。先其时发汗则痊愈，是指在不热无汗的时候，先用药取汗，则邪去卫和而痊愈。不然的话，汗液正在排泄时又发汗，难道没有汗出如水淋漓的祸患吗？
太阳病，发热汗出的，这是营弱卫强，所以导致汗出。想要救治邪风困扰的，适宜用桂枝汤。
这即是前条卫不协调、营自调和的意思，并申述其说。“救邪风者”，是救治卫气被风邪所扰乱。然而张仲景关于营弱卫强的说法，不过是阐明发热汗出的原因。后人不明察，于是有了风并于卫，卫实则营虚；寒中于营，营实则卫虚的说法。不知道邪气来自皮毛而入肌肉，无论中风伤寒，没有不波及卫气的。严重的，才一并伤及营气。郭白云所说的“涉卫中营”就是这种情况。所以寒邪浅的，仅伤于卫；风邪重的，便及于营。卫气实的，风邪也难泄；卫气虚的，寒邪也不固。无汗必须发其汗，麻黄汤所以去表实而发邪气；有汗不可更发汗，桂枝汤所以助表气而逐邪气。学医者只应当分辨病证有汗无汗，以严格区分麻黄汤和桂枝汤的使用，不必执着于营卫孰虚孰实，来证明伤寒和中风的差异。况且无汗为表实，何来卫虚之说？麻黄汤去除实邪，难道唯独遗漏卫气吗？能不拘泥于世俗说法的，才是豪杰之士。
Taiyang Wind-Strike (Taiyang Fengzhong). The pulse is floating on the superficial position (Yang) and weak on the deep position (Yin). Floating Yang indicates spontaneous heat; weak Yin indicates spontaneous sweating. With symptoms of aversion to cold, aversion to wind, mild fever, nasal congestion with rhonchi, and dry retching, Guizhi Tang (Cinnamon Twig Decoction) is indicated.
Taiyang Wind-Strike refers to the invasion of Wind Qi by the Yang aspect without yet affecting the Yin. Hence, the pulse is floating at Yang and weak at Yin. Floating Yang means heat arises spontaneously without needing to be constrained; weak Yin means sweat flows out spontaneously without needing to be forcibly released. The reason for this is that Wind is a Yang pathogen that moves upward, and Wei Qi (Defensive Qi) belongs to Yang and governs the exterior. When Yang (Wind) follows Yang (Wei Qi), the Qi becomes floating, hence heat arises spontaneously. The Yang Qi becomes strong due to Wind, while the Yin Qi, free from pathogens, appears relatively weak. When weakness follows strength, the Qi becomes depleted, hence sweat flows out. "Se se" (aversion to cold) and "xi xi" (aversion to wind) occur because the muscle pores are loose and Wei Qi is disharmonious. Although there is no actual cold, it feels like one cannot resist it; although there is no actual wind, one often feels chilly. "Xi" implies movement and flourishing, indicating that the heat fluctuates and intensifies, unlike the extreme heat of Cold Damage (Shanghan). Nasal congestion and dry retching are not only due to Wind Qi obstructing upwards but also represent the sudden aggravation of pathogens and the counter-action of Interior Qi rising. In such cases, Guizhi Tang (Cinnamon Twig Decoction) should be used to support the healthy Qi to expel pathogens and suppress external evils to pacify the interior.
Formula: Guizhi Tang (Cinnamon Twig Decoction)
Guizhi (Cinnamomi Ramulus, 3 liang, peeled)
Gancao (Glycyrrhizae Radix et Rhizoma, 2 liang, honey-fried)
Shaoyao (Paeoniae Radix Alba, 3 liang)
Shengjiang (Zingiberis Rhizoma Recens, 3 liang, sliced)
Dazao (Jujubae Fructus, 12 pieces, split)
Crush the above five herbs. Boil in 7 sheng of water with low heat until 3 sheng remain. Strain. Take when warm. Drink one sheng. Shortly after taking the medicine, drink more than one sheng of hot thin porridge to assist the medicinal power. Cover with blankets for about an hour until the whole body has a slight perspiration. This is ideal. Do not allow profuse sweating like flowing water, otherwise the disease will not be cured. If sweating occurs after the first dose and the disease resolves, stop taking the remaining medicine; do not finish the entire decoction. If no sweating occurs, administer another dose following the same method. If still no sweating, shorten the interval between doses, completing three doses within half a day. For severe cases, administer medicine over a day and night, observing for 24 hours. If symptoms persist after finishing one dose, prepare another. If no sweating occurs, continue up to two or three doses. Avoid raw/cold foods, sticky/slippery foods, meat, wheat products, five pungent spices, dairy/wine, and foul-smelling substances.
Commentary: Wind Qi can disturb Yang Qi and leak fluids, causing spontaneous heat and sweating, which differs from the spontaneous heat without sweating in Cold Damage (Shanghan). This formula uses Guizhi (Cinnamomi Ramulus) to disperse pathogens and Shaoyao (Paeoniae Radix Alba) to conserve fluids and Qi. Honey-fried Gancao (Glycyrrhizae Radix et Rhizoma) combined with the acridity of Guizhi is sufficient to repel external pathogens; combined with the sourness of Shaoyao, it is sufficient to pacify the interior. Shengjiang (Zingiberis Rhizoma Recens) and Dazao (Jujubae Fructus) combine sweet and acrid flavors to tonify Ying (Nutritive) and Wei (Defensive) Qi, assisting the healthy Qi in expelling pathogens. Because sweating has occurred but pathogens remain, Mahuang Tang (Ephedra Decoction) for releasing the exterior is not used. Because the exterior is affected but the interior lacks heat, Shigao (Gypsum Fibrosum) for clearing interior heat is not used; instead, Shaoyao (Paeoniae Radix Alba) is used to astringe Yin for treating the interior. This is why Guizhi Tang (Cinnamon Twig Decoction) differs from Mahuang Tang (Ephedra Decoction) and Da Qing Long Tang (Major Green Dragon Decoction). Drinking hot thin porridge shortly after taking the medicine aids Stomach Qi, thereby aiding medicinal power, as medicinal efficacy relies on Stomach Qi to circulate. Covering to induce slight perspiration prevents profuse sweating, adhering to the principle that "slight sweating indicates self-harmony, while excessive sweating indicates excess." Stopping subsequent doses after the first dose cures the disease signifies stopping upon hitting the target to avoid damaging healthy Qi. Shortening intervals for subsequent doses or administering up to three doses aims to decisively overcome the disease, stopping once sweating achieves harmony. Zhang Zhongjing demonstrates methods within methods here.
In Taiyang Disease, with symptoms of headache, fever, sweating, and aversion to wind, Guizhi Tang (Cinnamon Twig Decoction) is indicated.
When the Taiyang channel is invaded, whether by Wind-Strike or Cold Damage, both present with headache and fever. However, Cold Damage results in exterior excess with no sweating, while Wind-Strike results in exterior looseness with spontaneous sweating. Thus, headache and fever are common to both, but sweating and aversion to wind are unique to Wind-Strike. Wind-Strike must be treated with formulas for Wind. Stating "Guizhi Tang (Cinnamon Twig Decoction) is indicated" implies that no other formula can replace it.
In Taiyang Disease, if exterior signs have not resolved and the pulse is floating and weak, resolution via sweating is appropriate, preferably using Guizhi Tang (Cinnamon Twig Decoction).
Exterior signs of Taiyang include headache, fever, and aversion to wind/cold. If exterior signs persist, they should be resolved via sweating. However, treatment must be guided by the strength of the pulse. A floating and weak pulse indicates the pattern of floating Yang and weak Yin seen in Wind-Strike. Treatment should use Guizhi Tang (Cinnamon Twig Decoction) to support healthy Qi and expel pathogens.
In Taiyang Disease, if exterior signs have not resolved, purgation is contraindicated. Purgation is a regressive error. To resolve the exterior, Guizhi Tang (Cinnamon Twig Decoction) is indicated.
For pathogens in the exterior, diaphoresis is appropriate; for those in the interior, purgation is appropriate. This is a general principle. Therefore, if exterior signs persist, purgation is contraindicated. Purgation attacks the interior when the disease is in the exterior, constituting a regressive error. The text states: "If one should have induced sweating but instead purged, this is a regressive error. If one induces sweating first, the treatment is not regressive." This refers to the current situation. To resolve the exterior, Guizhi Tang (Cinnamon Twig Decoction) is the established method and should not be altered. Zhang Zhongjing warns against purgation for indications requiring diaphoresis in this manner.
Patients who frequently experience spontaneous sweating have harmonious Ying Qi (Nutritive Qi). Harmonious Ying Qi indicates external disharmony because Wei Qi (Defensive Qi) does not harmonize with Ying Qi. Since Ying Qi circulates within the vessels and Wei Qi circulates outside, inducing sweating again will restore harmony between Ying and Wei, leading to recovery. Guizhi Tang (Cinnamon Twig Decoction) is indicated.
This elaborates on the previous point regarding "weak Yin leads to spontaneous sweating." It explains that if Ying Qi is unharmed and harmonious, fluid metabolism proceeds naturally. If Wei Qi is disturbed by Wind and disharmonious, Yin loses protection, leading to spontaneous sweating. Ying and Wei are normally harmonious. Ying inside vessels guards Wei; Wei outside vessels protects Ying. Why would there be fever and aversion to cold? Only because Wei Qi becomes strong due to Wind, while Ying Qi appears weak due to lack of pathogenic interference. Pathogenic and healthy Qi differ in nature and strength, making harmony impossible. Thus, "harmonious Ying Qi with external disharmony" means it is not just Wei Qi that is diseased. To calm Ying Qi, one must harmonize Wei Qi; to harmonize Wei Qi, one must expel Wind. Guizhi Tang (Cinnamon Twig Decoction) is used to assist Yang and induce sweating. Sweating expels pathogens and harmonizes Wei Qi; harmonized Wei Qi no longer disturbs Ying Qi, leading to recovery.
If a patient has no internal organ diseases but experiences intermittent fever and spontaneous sweating without recovery, this is due to disharmonious Wei Qi (Defensive Qi). Inducing sweating before the onset of symptoms will lead to recovery. Guizhi Tang (Cinnamon Twig Decoction) is indicated.
The human body has meridians governing the exterior and organs managing transformation internally. Diseases may arise from exterior to interior or interior to exterior. No internal organ disease implies the interior is healthy. Intermittent fever and sweating imply periods without fever or sweating. Lack of recovery indicates the disease is in the exterior, not the interior, and involves Wei Qi (Defensive Qi), not Ying Qi (Nutritive Qi). Inducing sweating before onset works because applying medication during non-febrile, non-sweating periods expels pathogens and harmonizes Wei Qi. Otherwise, inducing sweating while fluids are already leaking could cause profuse sweating.
In Taiyang Disease, with fever and sweating, this indicates weak Ying Qi (Nutritive Qi) and strong Wei Qi (Defensive Qi), causing sweating. To rescue the Wei Qi disturbed by Wind pathogens, Guizhi Tang (Cinnamon Twig Decoction) is indicated.
This reiterates the concept of disharmonious Wei Qi and harmonious Ying Qi. "Rescuing Wind disturbance" means saving Wei Qi from Wind pathogen interference. Zhang Zhongjing's explanation of weak Ying and strong Wei merely elucidates the cause of fever and sweating. Later scholars misunderstood this, proposing that Wind combines with Wei making Wei excess and Ying deficiency, or Cold enters Ying making Ying excess and Wei deficiency. They failed to realize that pathogens enter from skin/hair into muscles, affecting Wei Qi in both Wind-Strike and Cold Damage. Severe cases affect Ying Qi, as described by Guo Baiyun ("passing through Wei to reach Ying"). Mild Cold affects only Wei; severe Wind affects Ying. Excess Wei resists Wind release; deficient Wei fails to secure against Cold. No sweating requires diaphoresis (Mahuang Tang/Ephedra Decoction removes exterior excess); sweating precludes further diaphoresis (Guizhi Tang/Cinnamon Twig Decoction assists exterior Qi to expel pathogens). Students should distinguish between Mahuang Tang (Ephedra Decoction) and Guizhi Tang (Cinnamon Twig Decoction) based on the presence or absence of sweating, rather than rigidly debating Ying/Wei deficiency/excess to differentiate Cold Damage from Wind-Strike. Exterior excess implies no sweating; how can Wei be deficient? Does Mahuang Tang (Ephedra Decoction) exclude Wei Qi when removing excess? Those who do not cling to conventional misconceptions are true heroes.