桂枝十八铢 芍药十八铢 甘草（炙）十八铢 石膏（碎，绵裹）二十四铢 麻黄（
去节）十八铢 大枣（擘）四枚 生姜一两二铢
右七味，以水五升，煮麻黄一、二沸，去上沫，内诸药，煮取二升，去滓，温服一升
。本方当裁为越婢汤、桂枝汤合之，饮一升。今合为一方，乃桂枝汤二分，越婢汤一
分。
【方解】
此方即大青龙汤以芍药易杏仁也，名虽越婢辅桂枝，实则大青龙汤之变制也。去杏仁
，恶其从阳而辛散；用芍药，以其走阴而酸收，以此易彼，裁而用之，则主治不同矣
。以桂枝二主之，则不发汗，可知越婢一者，乃麻黄石膏二物，不过取其辛凉之性，
佐桂枝二以和表而清肌热，则是寓微汗于不发之中，亦可识也。非若大青龙汤以石膏
佐麻黄，而为发汗驱肌热之重剂也。
【按】
桂枝二麻黄一汤，治形如疟，日再发者，汗出必解，而无热多寒少，故不用石膏之凉
也。桂枝麻黄各半汤，治如疟状，热多寒少，而不用石膏，更倍麻黄者，以其面有怫
郁热色，身有皮肤作痒，是知热不向里而向表，令得小汗，以顺其势，故亦不用石膏
之凉里也。桂枝二越婢一汤，治发热恶寒，热多寒少，而用石膏者，以其表邪寒少，
肌里热多；故用石膏之凉，佐麻桂以和荣卫，非发荣卫也。今人一见麻、桂，不问轻
重，亦不问温覆与不温覆，取汗与不取汗，总不敢用，皆因未究仲景之旨。麻黄、桂
枝只是荣卫之药，若重剂温覆取汗，则为发荣卫之药，轻剂不温覆取汗，则为和荣卫
之方也。
【集解】
吴人驹曰：发散表邪，皆以石膏同用者，盖石膏其性寒，寒能胜热；其味薄，薄能走
表。非若芩、连之辈，性寒味苦而厚，不能升达也。
@@@
伤寒，无大热，口燥渴，心烦，背微恶寒者，白虎加人参汤主之。
【注】
伤寒身无大热，不烦不渴，口中和，背恶寒，附子汤主之者，属少阴病也。今伤寒身
无大热，知热渐去表入里也。口燥渴心烦，知热已入阳明也。虽有背微恶寒一证，似
乎少阴，但少阴证，口中和，今口燥渴，是口中不和也。背恶寒、非阳虚恶寒，乃阳
明内热熏蒸于背，汗出肌疏，故微恶之也。主白虎汤，以直走阳明，大清其热，加人
参者，盖有意以顾肌疏也。
【集注】
喻昌曰：此条辨证最细。脉必滑而带浮，浑身无大热，又不恶寒，但背间微觉恶寒，
是表邪已将罢。其人口燥渴心烦，是里热已大炽。更不可姑待，而当急为清解，恐迟
则热深津竭，无济于事矣。
@@@
伤寒表不解，心下有水气，干呕发热而咳，或渴、或利、或噎、或小便不利，少腹满
，或喘者，小青龙汤主之。
【注】
伤寒表不解，谓脉浮紧、头痛、身痛、发热、无汗、恶寒之证仍在也。心下有水气，
谓干呕而咳也。然水之一为病不一，故曰：或渴、或利、或噎、或小便不利，少腹满
，或喘者，皆有水气之证，故均以小青龙汤，如法加减主之也。经曰：三焦者决渎之
官，水道出焉。膀胱者州都之官，津液藏焉，气化则能出矣。太阳受邪，若无水气，
病自在经，若有水气，病必犯府。病府则膀胱之气化不行，三焦之水气失道，停上焦
则或咳、或喘，或噎，停中焦则或渴、或干呕、或满，停下焦则或小便不利，少腹满
，或下利，凡水所行之处，皆得而病之也。小青龙汤外发太阳之表实，内散三焦之寒
饮，亦汗法中之峻剂，与大青龙汤并得其名。一以治太阳表实之热躁，一以治太阳表
实之寒饮也。
【集注】
程知曰：此明伤寒表证未解，水积心下，散寒涤饮法也。
汪琥曰：『明理论』云：青龙主风寒两伤之疾固已。伤寒表不解，则麻黄可以发；中
风表不解，则桂枝可以散。惟其表不解，而又加之心下有水气，则非二汤所能发散，
必以小青龙汤，始可祛除表里之邪气尔。
【方解】
这个方剂就是大青龙汤用芍药替换杏仁而成，名称虽然叫越婢加桂枝汤，实际上是大青龙汤的变方。去掉杏仁，是厌恶它性味辛散而助阳发散；使用芍药，是因为它性走阴分且酸收敛收，用此药替代彼药，裁减后使用，主治功效就不同了。以二分量的桂枝汤为主，则不发汗，由此可知越婢汤的一分量，不过是麻黄和石膏两味药，只是取它们辛凉的特性，辅助桂枝汤二分来调和表邪并清除肌热，这就是在“不发汗”中寓含“微汗”之意，也可以由此认识。不像大青龙汤用石膏辅助麻黄，作为发汗驱除肌热的重剂。
【按语】
桂枝二麻黄一汤，治疗症状像疟疾，一天发作两次的情况，出汗后必然痊愈，但没有“热多寒少”的症状，所以不用石膏的凉性。桂枝麻黄各半汤，治疗像疟疾一样的症状，热多寒少，但不用石膏，反而加倍使用麻黄，这是因为患者面部有郁滞的热色，身体皮肤瘙痒，由此可知热势不向体内发展而是趋向体表，让身体获得小汗，以顺应病势，所以也不用石膏的凉里作用。桂枝二越婢一汤，治疗发热恶寒，热多寒少的情况，而使用石膏，是因为表邪中寒少，肌肉内部热多；所以用石膏的凉性，辅助麻黄、桂枝来调和营卫，而不是发散营卫。现在的人一见麻黄、桂枝，不问病情轻重，也不问是否温覆取汗，总是不敢使用，这都是因为没有探究张仲景的本意。麻黄、桂枝只是调和营卫的药物，如果重用并温覆取汗，就成为发散营卫的药物；轻用且不温覆取汗，就成为调和营卫的方剂。
【集解】
吴人驹说：发散表邪，都用石膏配合使用，大概因为石膏性寒，寒能胜热；其味淡薄，薄能达表。不像黄芩、黄连这类药物，性寒味苦而厚重，不能升达体表。
伤寒，没有大热，口干燥渴，心烦，背部微微恶寒的，用白虎加人参汤主治。
【注】
伤寒身无大热，不烦不渴，口中平和，背部恶寒，用附子汤主治的，属于少阴病。现在伤寒身无大热，说明热势逐渐从体表进入体内。口干燥渴心烦，说明热已传入阳明经。虽然有背部微微恶寒这一症状，似乎像少阴病，但少阴病的特征是口中平和，现在口干燥渴，说明口中不和。背恶寒，不是阳气虚衰导致的恶寒，而是阳明内热熏蒸于背部，汗出导致肌肤疏松，所以感到轻微恶寒。主用白虎汤，直接作用于阳明经，大清其热；加入人参，是有意在顾护因汗出而疏松的肌表。
【集注】
喻昌说：这条文的辨证非常细致。脉象必定滑而带浮，浑身没有大热，也不恶寒，只是背部间微觉恶寒，这是表邪即将解除。患者口干燥渴心烦，说明里热已经非常炽盛。更不可姑且等待，而应当紧急清热解表，恐怕拖延则热邪深入、津液枯竭，就无济于事了。
@@@
伤寒表证未解，心下有水气，干呕、发热而咳嗽，或者口渴、或者腹泻、或者噎塞、或者小便不利、少腹胀满、或者喘息的，用小青龙汤主治。
【注】
伤寒表不解，指的是脉浮紧、头痛、身痛、发热、无汗、恶寒等症状仍然存在。心下有水气，指的是干呕和咳嗽。然而水饮致病表现不一，所以说：或者口渴、或者腹泻、或者噎塞、或者小便不利、少腹胀满、或者喘息，这些都是有水气的证候，所以都可用小青龙汤，按照方法加减后主治。经典记载：三焦是决渎之官，水道由此而出。膀胱是州都之官，津液藏于此，气化功能正常才能排出。太阳经受邪，如果没有水气，病自然在经脉；如果有水气，病必侵犯腑脏。病及腑脏，则膀胱的气化功能不行，三焦的水气失去常道，停在上焦则或咳、或喘、或噎，停在中焦则或渴、或干呕、或胀满，停在下焦则或小便不利、少腹胀满、或下利，凡是水液运行的地方，都可能因此生病。小青龙汤外发太阳表的实邪，内散三焦的寒饮，也是汗法中的峻剂，与大青龙汤齐名。一个用于治疗太阳表实的燥热，一个用于治疗太阳表实的寒饮。
【集注】
程知说：这阐明了伤寒表证未解，水饮积聚在心下，散寒涤除水饮的方法。
汪琥说：《明理论》云：青龙汤主治风寒两伤的疾病固然正确。伤寒表不解，则麻黄可以发汗；中风表不解，则桂枝可以解散。正因为表证未解，又加上心下有水气，那么单用这两个汤剂就不能发散，必须用小青龙汤，才能祛除表里的邪气。
[Formula Analysis]
This formula is derived from Da Qing Long Tang (Major Blue Dragon Decoction) by substituting Shaoyao (Paeoniae Radix Alba, 芍药) for Xingren (Armeniacae Semen Amarum, 杏仁). Although named Yue Bi Jia Gui Zhi Tang (Yuebi Plus Cinnamon Twig Decoction), it is essentially a modified version of Da Qing Long Tang. The removal of Xingren is due to its acrid and dispersing nature which aids Yang dispersion; the use of Shaoyao is because it enters the Yin aspect and has an astringent and收敛 (astringent) property. By substituting one for the other and modifying the dosage, the therapeutic indication changes. With two parts of Gui Zhi Tang (Cinnamon Twig Decoction) as the main component, it does not induce sweating. Thus, the one part of Yue Bi Tang consists merely of Mahuang (Ephedrae Herba, 麻黄) and Shigao (Gypsum Fibrosum, 石膏), utilizing their acrid-cool properties to assist the two parts of Gui Zhi Tang in harmonizing the exterior and clearing heat from the muscle layer. This implies inducing a slight sweat within the framework of "not inducing sweat," which can be understood from this perspective. It differs from Da Qing Long Tang, where Shigao assists Mahuang as a heavy agent to induce sweating and drive out muscle heat.
[Commentary]
Gui Zhi Er Ma Huang Yi Tang (Two Parts Cinnamon Twig and One Part Ephedra Decoction) treats symptoms resembling malaria, occurring twice daily, where sweating leads to resolution, but without the symptom pattern of "more heat than chills"; therefore, the cooling property of Shigao is not used. Gui Zhi Ma Huang Ge Ban Tang (Equal Parts Cinnamon Twig and Ephedra Decoction) treats symptoms resembling malaria with more heat than chills, yet it does not use Shigao and instead doubles the amount of Mahuang. This is because the patient presents with a flushed facial color indicating stagnant heat and skin itching, indicating that the heat is moving outward toward the exterior rather than inward. Allowing a slight sweat helps follow the pathogenic trend; thus, the cooling interior effect of Shigao is also not used. Gui Zhi Er Yue Bi Yi Tang (Two Parts Cinnamon Twig and One Part Yuebi Decoction) treats fever and aversion to cold with more heat than chills, and uses Shigao because there is little cold on the exterior but much heat in the muscle interior. Therefore, the cooling property of Shigao is used to assist Mahuang and Gui Zhi in harmonizing Ying and Wei (Nutritive and Defensive Qi), rather than dispersing them. Modern practitioners often hesitate to use Mahuang and Gui Zhi regardless of severity or whether warming covers are applied to induce sweat, simply because they have not investigated the intent of Zhang Zhongjing. Mahuang and Gui Zhi are agents for harmonizing Ying and Wei; if used in heavy doses with warming covers to induce sweat, they become agents for dispersing Ying and Wei; if used in light doses without warming covers to avoid inducing sweat, they become formulas for harmonizing Ying and Wei.
[Collected Explanations]
Wu Renju stated: To disperse exterior pathogens, Shigao is always used in combination. This is likely because Shigao is cold in nature, and cold can overcome heat; its taste is thin, and thinness can reach the exterior. It is unlike Huang Qin (Scutellariae Radix, 黄芩) and Lian Qiao (or Huang Lian, Coptidis Rhizoma, 黄连), which are cold in nature but bitter and thick in taste, unable to ascend to the surface.
In Shang Han (Cold Damage), presenting with no significant fever, dry mouth and thirst, irritability, and slight aversion to cold on the back, Bai Hu Jia Ren Shen Tang (White Tiger Plus Ginseng Decoction) is the primary treatment.
[Note]
When Shang Han presents with no significant body heat, absence of irritability and thirst, a normal mouth sensation, and aversion to cold on the back, Fu Zi Tang (Aconite Decoction) is used, which belongs to Shao Yin disease. In the current case, Shang Han presents with no significant body heat, indicating that heat is gradually moving from the exterior to the interior. Dry mouth, thirst, and irritability indicate that heat has entered the Yang Ming channel. Although there is a symptom of slight aversion to cold on the back, which seems like Shao Yin, Shao Yin syndrome is characterized by a normal mouth sensation; here, dry mouth and thirst indicate the mouth is not normal. The aversion to cold on the back is not due to Yang deficiency, but rather Yang Ming internal heat steaming upwards to the back, causing sweating and skin laxity, leading to slight aversion to cold. Bai Hu Tang (White Tiger Decoction) is primarily used to directly target the Yang Ming channel and clear heat significantly; Ren Shen (Ginseng Radix, 人参) is added to protect the lax skin/muscle layer.
[Collected Notes]
Yu Chang stated: The differentiation in this clause is very detailed. The pulse must be slippery and floating. There is no significant heat over the whole body, nor aversion to cold, only slight aversion to cold in the back area, indicating that exterior pathogens are about to resolve. The patient's dry mouth, thirst, and irritability indicate that interior heat is already blazing. One must not delay; immediate clearing and resolving are necessary. If delayed, deep heat and exhausted fluids will make treatment futile.
@@@
In Shang Han, if the exterior syndrome is unresolved and there is water qi under the heart (epigastrium), presenting with dry retching, fever, and cough, or alternatively thirst, diarrhea, choking sensation, dysuria with lower abdominal fullness, or wheezing, Xiao Qing Long Tang (Minor Blue Dragon Decoction) is the primary treatment.
[Note]
"Exterior syndrome unresolved" refers to the persistence of symptoms such as floating-tight pulse, headache, body pain, fever, absence of sweat, and aversion to cold. "Water qi under the heart" refers to dry retching and cough. However, water pathology manifests in various ways; hence, the text mentions: alternatively thirst, diarrhea, choking, dysuria with lower abdominal fullness, or wheezing. These are all signs of water qi retention. Therefore, Xiao Qing Long Tang should be used with appropriate modifications for each case. The Classics state: The San Jiao (Triple Burner) is the official of irrigation, through which water passages flow. The Bladder is the official of the capital, storing fluids, which are excreted only when Qi transformation occurs. When the Tai Yang (Greater Yang) channel receives pathogens, if there is no water qi, the disease remains in the channels; if there is water qi, the disease invades the fu organs. Invading the fu organs causes the Qi transformation of the Bladder to fail and the water qi of the San Jiao to lose its pathway. Retention in the Upper Jiao causes cough, wheezing, or choking; retention in the Middle Jiao causes thirst, dry retching, or fullness; retention in the Lower Jiao causes dysuria, lower abdominal fullness, or diarrhea. Wherever water flows, pathology may occur. Xiao Qing Long Tang releases exterior excess of Tai Yang externally and dissipates cold-fluid retention in the San Jiao internally. It is a potent diaphoretic agent, sharing fame with Da Qing Long Tang. One treats heat-agitation due to Tai Yang exterior excess, while the other treats cold-fluid retention due to Tai Yang exterior excess.
[Collected Notes]
Cheng Zhi stated: This clarifies the method of dispelling cold and purging fluid retention when the exterior syndrome of Shang Han is unresolved and water accumulates under the heart.
Wang Hu stated: According to "Ming Li Lun" (Theory Clarification), Qing Long Tang indeed treats diseases caused by both wind and cold. In Shang Han with unresolved exterior, Mahuang can induce sweating; in Feng Biao (Wind Strike) with unresolved exterior, Gui Zhi can disperse. Precisely because the exterior is unresolved and compounded by water qi under the heart, neither of the two previous decoctions can disperse the pathogen; only Xiao Qing Long Tang can eliminate both exterior and interior pathogens.