太阳主表，故立方以发表为主，而发表中更兼治里，故种种不同。麻黄汤于发表中降气，桂枝汤于发表中
滋阴，葛根汤于发表中生津，大青龙汤与麻杏甘膏汤、麻翘赤豆汤，于发表中清火，小青龙汤与五苓散，于发
表中利水，清火中复有轻重，利水中各有浅深也。若白虎之清火，十枣之利水，又解表后之证治。其陷胸、泻
心、抵当、调胃、四逆、真武等剂，又随症救逆之法矣。大抵太阳之表，不离桂枝、麻黄二汤加减，以心为太
阳之里也。今将诸方详论，表章仲景治法，令后人放胆用之，则麻黄汤治伤寒而不治中风。桂枝汤治中风而不
治伤寒等说，其可少息乎？
桂枝汤∶
桂枝 芍药 甘草 生姜 大枣
此为仲景群方之魁，乃滋阴和阳，调和营卫，解肌发汗之总方也。凡头痛发热恶风恶寒，其脉浮而弱，汗
自出者，不拘何经，不论中风、伤寒、杂病，咸得用此发汗。若妄汗妄下，而表不解者，仍当用此解肌。如所
云头痛、发热、恶寒、恶风、鼻鸣干呕等病，但见一症即是，不必悉具，惟以脉弱自汗为主耳。桂枝赤色，
通心温经，能扶阳散寒，甘能益气生血，辛能解散外邪，内辅君主，发心液而为汗。故麻黄、葛根、青龙辈，
凡发汗御寒者咸用之，惟桂枝汤不可用麻黄，麻黄汤不可无桂枝也。本方皆辛甘发散，惟芍药微苦微寒，能益
阴敛血，内和营气。先辈之无汗不得用桂枝汤者，以芍药能止汗也。芍药之功，本在止烦，烦止汗亦止，故反
烦、更烦，与心悸而烦者咸赖之。若倍加芍药，
即建中之剂，非复发汗之剂矣。是方也，用桂枝发汗，即用芍药止汗，生姜之辛，佐桂以解肌，大枣之甘，佐
芍以和里。桂、芍之相须，姜、枣之相得，阴阳表里，并行而不悖，是刚柔相济以为和也。甘草甘平，有安内
攘外之功，用以调和气血者，即以调和表里，且以调和诸药矣。而精义尤在啜稀热粥以助药力。盖谷气内充，
外邪勿复入，热粥以继药之后，则余邪勿复留，复方之妙用又如此。故用之发汗，自不至于亡阳；用之止汗，
自不至于贻患。今人凡遇发热，不论虚实，悉忌谷味，刊桂枝方者，俱削此法，是岂知仲景之心法乎？要知此
方专治表虚，但能解肌，以发营中之汗，不能开皮毛之窍，以出卫分之邪。故汗不出者，是麻黄症，脉浮紧者，
是麻黄脉，即不得与桂枝汤矣。然初起无汗，当用麻黄发汗。如汗后复烦，即脉浮数者，不得再与麻黄而更用
桂枝。如汗后不解，与下后脉仍浮，气上冲，或下利止而身痛不休者，皆当用此解外。盖此时表虽不解，腠理
已疏，邪不在皮毛而在肌肉。故脉证虽同麻黄，而主治当属桂枝也。粗工妄谓桂枝汤专治中风一证，印定后
人耳目，而所称中风者，又与此方不合，故置之不用。愚常以此汤治自汗、盗汗、虚虐、虚痢，随手而愈。因
知仲景方可通治百病，与后人分门证类，使无下手处者，可同年而语耶？
麻黄汤∶
麻黄 桂枝 杏仁 甘草
治风寒在表，头痛项强，发热身痛，腰痛，骨节烦疼，恶风恶寒，无汗，胸满而喘，其脉浮紧浮数者，此
为开表逐邪发汗之峻剂也。古人用药用法象之义，麻黄中空外直，宛如毛窍骨节，故能去骨节之风寒，从毛窍
而出，为卫分发散风寒之品。桂枝之条纵横，宛如经脉系络，能入心化液，通经络而出汗，为营分散解风寒之
品。杏仁为心果，温能助心散寒，苦能清肺下气，为上焦逐邪定喘之品。甘草甘平，外拒风寒，内和气血，为
中宫安内攘外之品。此汤入胃行气于玄府，输精于皮毛，斯毛脉合精而溱溱汗出，在表之邪，其尽去而不留，
痛止喘平，寒热顿解，不烦啜粥而藉汗于谷也。其不用姜、枣者，以生姜之性，横散解肌，碍麻黄之上升；大
枣之性，滞泥于膈，碍杏仁之速降。此欲急于直达，稍缓则不迅，横散则不峻矣。若脉浮弱汗自出者，或尺
脉微迟者，是桂枝所主，非此方所宜。盖此乃纯阳之剂，过于发散，如单刀直入之将，投之恰当，一战成功，
不当则不戢而召祸。故用之发
表，可一而不可再，如汗后不解，盒饭以桂枝汤代之。若汗出不透，邪气留连于皮毛骨肉之间，又有麻桂合半与
桂枝二麻黄一之妙用。若阳盛于内而无汗者，又有麻黄杏仁石膏连翘赤小豆等剂。此皆仲景心法也。予治冷风
哮与风寒湿三气成痹等证，用此辄效，非伤寒一证可拘也。按∶麻、桂二方，治伤寒中风者，遇当用而不敢用，
注疏伤寒家于不当用者，妄言其当用。如太阳衄血证，宜桂枝汤句，语意在当须发汗下，麻黄主之句，在当发
其汗下，二句皆于结句补出，是倒序法也。仲景于论证时，细明其所以然，未及于方故耳。夫桂枝乃行血之品，
仲景用桂枝发汗，不是用桂枝止衄，是用在未衄时，非用在已衄后，且夺血者无汗，此理甚明。麻黄乃上升之
品，夫既云衄乃解，又云自衄者愈，若复用升提之药，衄流不止可必矣，且衄家不可发汗，此禁甚明矣。又如
小青龙主之句，语意在服汤已上，岂有寒去欲解，反用燥热之剂，重亡津液，令渴不解乎？且云服药已，服药
已者，是何药何汤耶？观仲景于所服药不合法者，必明斥之。如所云“服泻心汤，复以他药下之，利不止。”又
云“知医以他药下之，非其治也。”粗工不知倒序等法，又溺于风寒二字，而曰是虽热甚，邪由在经，以麻黄
治衄，是发散经中邪气耳。请问邪气寒乎？热乎？若寒邪则血凝不流，焉得有衄？若热邪则清降不遑，而敢升
发耶？且云点滴不成流者，必用服药。若成流不止，将何法以善其后乎？此误天下苍生之最盛者，余因表而出
之。
葛根汤∶
葛根 麻黄 桂枝 白芍 甘草 姜枣
治头项强痛，背亦强，牵引KT KT 然，脉浮无汗恶寒，兼治风寒在表而自利者，此开表逐邪之轻剂也。
其证身不疼，腰不痛，骨节不痛，是骨不受寒矣。头项强痛，下连于背，牵引不宁，是筋伤于风矣。不喘不烦
躁，不干呕，是无内症；无汗而恶风，病只在表；若表病而兼下利，是表实里虚矣。比麻黄、青龙之剂较轻，
然KT KT 更甚于项强，而无汗不失为表实，脉浮不紧数，是中于鼓动之阳风，故以桂枝汤为主，而加麻、
葛以攻其表实也。葛根味甘气凉，能起阴气而生津液，滋筋脉而舒其牵引，故以为君。麻黄、生姜，能开玄
府腠理之闭塞，祛风而出汗，故以为臣。寒热俱轻，故少佐桂、芍，同甘、枣以和里。此于麻、桂二方之间，
衡其轻重，而为调和表里之剂也。故用之以治表实，而外邪
自解，不必治里虚，而下利自瘳，与大青龙治表里俱实者异矣。要知葛根秉性轻清，赋体浓重，轻可去实，重
可镇动，浓可固里，一物而三美备。然惟表实里虚者宜之，胃家实者，非所宜也。故仲景于阳明经中不用葛根。
东垣用药分经，不列于太阳，而列于阳明。易老云∶“未入阳明者不可服。”皆未知此义。喻氏谓“仲景不用
于阳明，恐亡津液，”与本草生津之说左。又谓“能开肌肉，”又与仲景治汗出恶风桂枝汤中加葛根者左矣。
盖桂枝葛根俱是解肌和里之剂，故有汗无汗，下利不下利，皆可用，与麻黄专于治表者不同。麻黄葛根俱有沫，
沫者浊气也。故仲景皆以水煮去其沫，而后入诸药，此取其清扬发腠理之义。桂枝汤啜稀粥者，因无麻黄之开，
而有芍药之敛，恐邪有不尽，故假谷气以逐之，此汗生于谷也。
大青龙汤∶
麻黄 桂枝 石膏 杏仁 甘草 姜枣
太阳中风，脉浮紧，头痛发热，恶寒身疼，不汗出而烦躁，此麻黄证之剧者，故加味以治之也。诸证全是
麻黄，有喘与烦躁之别。喘者是寒郁其气，升降不得自如，故多用杏仁之苦以降气；烦躁是热伤其气，无津不
能作汗，故特加石膏之甘以生津。然其性沉而大寒，恐内热顿除而表寒不解，变为寒中而挟热下利，是引贼破
家矣。故必倍麻黄以发表，又倍甘草以和中，更用姜枣以调营卫。一汗而表里双解，风热两除，此大青龙清内
攘外之功，所以佐麻、桂二方之不及也。夫青龙以发汗命名，其方分大小，在麻黄之多少，而不关石膏，观小
青龙之不用可知。石膏不能驱在表之风寒，但能清中宫之燔灼，观白虎之多用可知。世不知石膏为烦躁用，妄
为发汗用，十剂之轻可去实，岂至坚至重之质而能发汗哉？汗多亡阳者，过在麻黄耳。少阴亦有发热恶寒烦躁
之症，与大青龙同，但脉不浮、头不痛为异。若脉浮弱汗自出者，是桂枝证。二证妄与石膏，则胃气不至于四
肢而手足厥冷；妄用麻黄，则卫阳不周于身而筋惕肉 。此仲景所深戒也。要知少阴见阳证而用麻黄，必固以
附子。太、少异位，阴阳殊途，故寒温有别。桂枝证之烦，因于木旺，故用微苦微寒之剂以升降之；大青龙之
兼躁，因于风动，故用至阴至重之品以镇坠之。有汗无汗，虚实不同，轻重有差也。必细审其所不用，然后不
失其所当用耳。
按∶许叔微云∶“桂枝治中风，麻黄治伤寒，大青龙治中风见寒脉、
伤寒见风脉，三者如鼎立。”此方氏三大纲所由来。而大青龙之证治，自此不明于世矣。不知仲景治表，只
在麻、桂二法，麻黄治表实，桂枝治表虚，方治在虚实上分，不在风寒上分也。盖风寒二证，俱有虚实，俱有
浅深，俱有营卫，大法又在虚实上分浅深，并不在风寒上分营卫也。夫有汗为表虚，立桂枝汤治有汗之风寒，
而更有加桂去桂、加芍去芍，及加附子、人参、浓朴、杏仁、茯苓、白术、大黄、龙骨、牡蛎等剂，皆是桂
枝汤之变局。因表虚中更有内虚内实浅深之不同，故加减法亦种种不一耳。以无汗为表实，而立麻黄汤治无汗
之风寒，然表实中亦有夹寒夹暑、内寒内热之不同，故以麻黄为主而加减者，若葛根汤，大小青龙、麻黄附子
细辛甘草、麻黄杏仁甘草石膏、麻黄连翘赤豆等剂，皆麻黄汤之变局，因表实中亦各有内外寒热浅深之殊也。
葛根汤因肌肉津液不足，而加芍药、葛根，大青龙因内热烦躁而加石膏，小青龙以干呕而咳，而加半夏、细辛、
干姜，麻黄附子细辛甘草二方，以脉沉而加附子，若连翘赤豆梓皮，湿热发黄而加。诸剂皆因表实，从麻黄汤
加减，何得独推大青龙为鼎立耶？何但知有风寒，而不知有风热，但知有中风见寒、伤寒见风之症，而不知小
青龙之治风寒、大青龙之治风热、麻杏甘膏之治温热、麻翘豆汤之治湿热，表实中更有如是之别耶？且前辈之
凿分风寒者，拘于脉耳。不知仲景之论脉甚活而不拘，如大青龙之条，有中风而脉浮紧、伤寒而脉浮缓，是互
文见意处。言中风脉缓，然亦有脉浮紧者；伤寒脉紧，然亦有脉浮缓者。盖中风伤寒，各有浅深，或因人之强
弱而异，地之高下而异，时之乖和而异。证既不可拘，脉即不可执。如阳明中风而脉浮紧，太阴伤寒而脉浮缓，
不可谓脉紧必伤寒，脉缓必中风矣。按《内经》脉滑曰风，则风脉原无定象；又盛而紧曰胀，则紧脉不专属伤
寒；又缓而滑为热中，则缓脉亦不专指中风矣。且阳明中风，有脉浮而紧者，又有脉弦浮大者。必欲以太阳之
脉缓自汗、脉紧无汗，定分风寒，割裂营卫，他经皆有中风，皆不言及何耶？要知脉紧固为有力，脉浮缓亦不
是浮弱，即《内经》缓而滑为热中之脉也。盖仲景凭脉辨证，只审虚实。故不论中风伤寒脉之缓紧，但于指下
有力者为实，脉弱无力者为虚；不汗出而烦躁者为实，汗出多而烦躁者为虚；证在太阳而烦躁者为实，证在少
阴而烦躁者为虚。实者可服大青龙，虚者便不可服，此最易知也。凡先烦不躁而脉浮者，必有汗而自解；烦躁
而脉浮紧者，必无汗而
不解。大青龙汤为风寒在表而兼热中者设，不是为有表无里而设。故中风无汗烦躁者可用，伤寒而无汗烦躁者亦
可用。盖风寒本是一气，故汤剂可以互投。论中有中风伤寒互称者，如大青龙是也；有中风伤寒兼提者，如小
柴胡是也。仲景但细辨脉症而施治，何尝拘拘于中风伤寒之别其名乎？如既立麻黄汤治寒，桂枝汤治风，而中
风见寒、伤寒见风者，曷不用桂枝麻黄合半汤，而更用大青龙为主治耶？且既有中风恶风不恶寒，伤寒恶寒不
恶风之说，曷不用大青龙之恶寒主伤寒，麻黄证之恶风主中风，桂枝证之恶风复恶寒，主中风见寒、伤寒见
风耶？方氏因三纲之分，而有风寒多少之陋见。喻氏又因大青龙之名，而为龙背龙腹龙尾之奇说。又谓纵横者，
龙之所以飞期门及大青龙之位。青龙之说愈工，而青龙之法愈湮，此所谓好龙而不识真龙者也。大青龙之点睛，
在无汗烦躁、无少阴证二句。合观之，知本方本为太阳烦躁而设。仲景恐人误用青龙；不特为脉弱汗出者禁，
而吃紧尤在少阴。盖少阴亦有发热、恶寒、身疼、无汗而烦躁之症，此阴极似阳，寒极反见热化也。误用则厥
逆筋惕肉 所必至，全在此处着眼，故必审其非少阴证，而为太阳烦躁无疑。太阳烦躁为阳盛，非大青龙不解。
太阳经主司体表，因此治疗太阳病的方剂以发散表邪为主，而在发散表邪的同时又兼顾治疗里证，所以方剂种类繁多各不相同。麻黄汤在发散表邪的同时降逆气，桂枝汤在发散表邪的同时滋养阴液，葛根汤在发散表邪的同时生津液，大青龙汤与麻杏甘膏汤、麻黄连翘赤小豆汤，在发散表邪的同时清泄火热，小青龙汤与五苓散，在发散表邪的同时利水湿，清火有轻重之分，利水有深浅之别。至于白虎汤的清火，十枣汤的利水，又是解表之后的证治方法。那些陷胸汤、泻心汤、抵当汤、调胃承气汤、四逆汤、真武汤等方剂，又是随病症变化而救逆的方法。大体而言，太阳表的病证，离不开桂枝汤和麻黄汤的加减运用，因为心是太阳的里位。现在详细论述这些方剂，彰显张仲景的治疗法则，让后人敢于使用，那么“麻黄汤只治伤寒而不治中风，桂枝汤只治中风而不治伤寒”这类说法，是否可以稍微停息了呢？
桂枝汤：
桂枝、芍药、甘草、生姜、大枣
这是张仲景众多方剂中的魁首，是滋阴和阳、调和营卫、解肌发汗的总方。凡是头痛、发热、恶风、恶寒，脉象浮而弱，自然出汗的患者，不论属于哪一经，也不论是中风、伤寒还是杂病，都应当用此方发汗。如果误用发汗或误用攻下，导致表证未解，仍然应当用此方解肌。如所说的头痛、发热、恶寒、恶风、鼻鸣、干呕等症状，只要见到其中一种症状即可，不必全部具备，主要以脉弱、自汗为主要依据。桂枝色赤，通心温经，能扶助阳气驱散寒邪，甘味能益气生血，辛味能解散外邪，内助心主，激发心液化为汗。所以麻黄、葛根、青龙汤类，凡是发汗御寒的药物都用到它，只有桂枝汤不可加麻黄，麻黄汤不可没有桂枝。本方都是辛甘发散之品，只有芍药微苦微寒，能益阴敛血，内和营气。前辈说无汗者不能用桂枝汤，是因为芍药能止汗。芍药的功效，本来在于止烦，烦止汗也就止了，所以出现反烦、更烦，以及心悸而烦的情况，都依赖它。如果加倍使用芍药，就成为建中类的方剂，而不是再次发汗的方剂了。这个方子，用桂枝发汗，就用芍药止汗，生姜的辛味，辅助桂枝解肌，大枣的甘味，辅助芍药和里。桂枝与芍药的相互配合，生姜与大枣的相得益彰，阴阳表里，并行不悖，这是刚柔相济以达到和谐。甘草味甘平，有安内攘外的功效，用来调和气血，也就是调和表里，并且调和诸药。其中的精妙之处尤其在于喝热稀粥以助药力。因为谷气在内充实，外邪就不再进入，热粥继服药之后服用，那么残余的病邪就不再停留，复方奥妙的运用又如此。所以用它发汗，自然不会导致亡阳；用它止汗，自然不会留下后患。现在的人凡是遇到发热，不论虚实，都忌讳谷物食物，刊印桂枝汤方的人，都删去了喝粥这个方法，这哪里懂得张仲景的心法呢？要知道此方专门治疗表虚，只能解肌，发出营分中的汗，不能打开皮毛的毛孔，排出卫分中的邪气。所以不出汗的，是麻黄汤证，脉浮紧的，是麻黄汤脉，就不可以用桂枝汤了。然而初起无汗，应当用麻黄汤发汗。如果发汗后再次出现烦躁，即使脉浮数，也不可以再给麻黄汤，而改用桂枝汤。如果发汗后病不解，或者攻下后脉仍然浮，气上冲，或者腹泻停止但身体疼痛不止的，都应当用此方解表。因为此时虽然表证未解，但腠理已疏松，邪气不在皮毛而在肌肉。所以脉证虽然与麻黄汤证相同，但主治应当归属桂枝汤。庸医胡乱说桂枝汤专门治疗中风一证，束缚了后人的耳目，而他们所称的中风，又与此方不合，所以放置不用。我常常用此汤治疗自汗、盗汗、虚疟、虚痢，随手而愈。由此知道张仲景的方子可以通治百病，与后人分门别类使医生无从下手的情况，岂能相提并论呢？
麻黄汤：
麻黄、桂枝、杏仁、甘草
治疗风寒在表，头痛项强，发热身痛，腰痛，骨节烦疼，恶风恶寒，无汗，胸满而喘，脉象浮紧或浮数的，这是开表逐邪发汗的峻猛剂型。古人用药用法象的意义，麻黄中空外直，宛如毛窍骨节，所以能去除骨节间的风寒，从毛窍而出，是卫分发散风寒的药物。桂枝枝条纵横，宛如经脉系络，能入心化液，通经络而出汗，是营分散解风寒的药物。杏仁为心果，温性能助心散寒，苦性能清肺下气，是上焦逐邪定喘的药物。甘草味甘平，外拒风寒，内和气血，是中宫安内攘外的药物。此汤入胃行气于玄府（汗孔），输精于皮毛，这样毛脉合精而溱溱汗出，在表的邪气，就能全部去除而不留，痛止喘平，寒热顿解，不需要喝粥来借谷气发汗。它不用姜、枣的原因，是因为生姜的性质横散解肌，妨碍麻黄的上升；大枣的性质滞泥于膈，妨碍杏仁的快速下降。这是想要急于直达病所，稍缓则不迅速，横散则不峻猛了。如果脉浮弱自汗出的，或者尺脉微迟的，是桂枝汤的主治，不是此方适宜的。因为这纯阳之剂，过于发散，像单刀直入的将领，投用恰当，一战成功，不恰当就会不收敛而招致祸患。所以用它发表，可以一次而不可以再用，如果发汗后病不解，应当用桂枝汤代替。如果汗出不透，邪气留连在皮毛骨肉之间，又有麻桂各半汤与桂枝二麻黄一汤的妙用。如果阳盛于内而无汗的，又有麻黄杏仁石膏连翘赤小豆等方剂。这都是张仲景的心法。我治疗冷风哮与风寒湿三气成痹等证，用此方往往有效，不仅仅是拘泥于伤寒一证。按语：麻黄、桂枝两方，治疗伤寒中风的，遇到应当用而不敢用，注疏伤寒的医家在不应当用的地方，妄言其应当用。如太阳衄血证宜用桂枝汤这句话，语意是在应当发汗攻下的时候，麻黄主之这句话，是在应当发其汗下的时候，这两句都是在结尾处补出来的，是倒序写法。张仲景在论证时，详细说明其所以然，还没来得及涉及方剂罢了。桂枝是行血的药物，张仲景用桂枝发汗，不是用桂枝止衄血，是用在未衄血之前，不是用在已衄血之后，况且夺血者无汗，这个道理很明显。麻黄是上升的药物，既然说衄血乃解，又说自衄者愈，如果再复用升提的药物，衄血不止是必然的，况且衄血家不可发汗，这个禁忌非常明显。又如小青龙主之这句话，语意是在服药之后，难道寒气去欲解时，反而用燥热的剂型，重新耗伤津液，令口渴不解吗？而且说服药已，服药已，是什么药什么汤呢？看张仲景对于所服药物不合法的，必定明确斥责。如所说的“服泻心汤，复以他药下之，利不止。”又说“知医以他药下之，非其治也。”庸医不知道倒序等方法，又沉溺于风寒二字，说虽然是热甚，邪气在经，用麻黄治衄，是发散经中邪气罢了。请问邪气是寒还是热？如果是寒邪则血凝不流，怎么会有衄血？如果是热邪则清降还来不及，怎么敢升发呢？而且说点滴不成流的，必须用服药。如果成流不止，将用什么方法来善后呢？这是误天下苍生最严重的错误，我因此表白并指出它。
葛根汤：
葛根、麻黄、桂枝、白芍、甘草、姜、枣
治疗头项强痛，背部也强，牵引拘急不适，脉浮无汗恶寒，兼治风寒在表而自利的，这是开表逐邪的轻剂。其证身不疼，腰不痛，骨节不痛，是骨不受寒了。头项强痛，下连于背，牵引不宁，是筋伤于风了。不喘不烦躁，不干呕，是无内症；无汗而恶风，病只在表；如果表病而兼下利，是表实里虚了。比麻黄汤、青龙汤的剂型较轻，但是项背强几几更甚于项强，而无汗不失为表实，脉浮不紧数，是中于鼓动之阳风，所以以桂枝汤为主，而加麻黄、葛根以攻其表实。葛根味甘气凉，能起阴气而生津液，滋筋脉而舒其牵引，所以作为君药。麻黄、生姜，能开玄府腠理的闭塞，祛风而出汗，所以作为臣药。寒热俱轻，所以少佐桂枝、芍药，同甘草、大枣以和里。这是在麻黄、桂枝两方之间，权衡其轻重，而为调和表里的剂型。所以用它治疗表实，而外邪自然解除，不必治里虚，而下利自然痊愈，与大青龙汤治疗表里俱实的不同。要知道葛根秉性轻清，赋体浓重，轻可去实，重可镇动，浓可固里，一物而三美备。然而只有表实里虚者适宜，胃家实的，不适宜。所以张仲景在阳明经中不用葛根。李东垣用药分经，不列于太阳，而列于阳明。易老说：“未入阳明者不可服。”都不知道这个意义。喻嘉言说“张仲景不用於阳明，恐亡津液”，与本草生津的说法相反。又说“能开肌肉”，又与张仲景治疗汗出恶风在桂枝汤中加葛根的说法相反。大概桂枝、葛根都是解肌和里的剂型，所以有汗无汗，下利不下利，都可以用，与麻黄专于治表的不同。麻黄、葛根都有沫，沫者是浊气。所以张仲景都以水煮去其沫，而后入诸药，这是取其清扬发腠理的意义。桂枝汤喝稀粥的原因，是因为没有麻黄的开泄，而有芍药的收敛，恐怕邪气不尽，所以借谷气以驱逐它，这是汗生于谷。
大青龙汤：
麻黄、桂枝、石膏、杏仁、甘草、姜、枣
太阳中风，脉浮紧，头痛发热，恶寒身疼，不汗出而烦躁，这是麻黄证的剧烈者，所以加味以治疗它。各种证候全是麻黄汤证，区别在于喘与烦躁。喘是寒郁其气，升降不得自如，所以多用杏仁的苦味以降气；烦躁是热伤其气，无津不能作汗，所以特别加石膏的甘味以生津。然而石膏性质沉而大寒，恐怕内热顿除而表寒不解，变为寒中而挟热下利，这是引贼破家了。所以必须倍用麻黄以发表，又倍用甘草以和中，更用姜枣以调营卫。一汗而表里双解，风热两除，这是大青龙清内攘外的功效，所以辅助麻黄、桂枝两方的不足。夫青龙以发汗命名，其方分大小，在于麻黄的多少，而不关乎石膏，看小青龙汤不用石膏就知道了。石膏不能驱散在表的风寒，只能清中宫的燔灼，看白虎汤的多用就知道了。世人不知道石膏是为烦躁用的，妄以为是发汗用的，十剂中的轻可去实，难道是至坚至重的质地能发汗吗？汗多亡阳的过错，在于麻黄罢了。少阴也有发热恶寒烦躁的症状，与大青龙汤相同，但脉不浮、头不痛为异。如果脉浮弱自汗出的，是桂枝证。这两个证候妄用石膏，则胃气不至于四肢而手足厥冷；妄用麻黄，则卫阳不周于身而筋惕肉瞤。这是张仲景所深深告诫的。要知道少阴见阳证而用麻黄，必须固护以附子。太、少异位，阴阳殊途，所以寒温有别。桂枝证的烦，因于木旺，所以用微苦微寒的剂型以升降之；大青龙汤的兼躁，因于风动，所以用至阴至重的物品以镇坠之。有汗无汗，虚实不同，轻重有差。必须仔细审察其所不用的，然后不失其所应当用的。
按语：许叔微说：“桂枝治中风，麻黄治伤寒，大青龙治中风见寒脉、伤寒见风脉，三者如鼎立。”这是方氏三大纲的来源。而大青龙汤的证治，从此就不明于世了。不知道张仲景治表，只在麻、桂两法，麻黄治表实，桂枝治表虚，方治在虚实上分，不在风寒上分。大概风寒两证，俱有虚实，俱有浅深，俱有营卫，大法又在虚实上分浅深，并不在风寒上分营卫。有汗为表虚，立桂枝汤治有汗的风寒，而更有加桂去桂、加芍去芍，及加附子、人参、浓朴、杏仁、茯苓、白术、大黄、龙骨、牡蛎等方剂，都是桂枝汤的变局。因为表虚中更有内虚内实浅深之不同，所以加减法也种种不一。以无汗为表实，而立麻黄汤治无汗的风寒，然而表实中亦有夹寒夹暑、内寒内热之不同，所以以麻黄为主而加减的，若葛根汤，大小青龙、麻黄附子细辛甘草、麻黄杏仁甘草石膏、麻黄连翘赤小豆等方剂，都是麻黄汤的变局，因为表实中亦各有内外寒热浅深之殊。葛根汤因肌肉津液不足，而加芍药、葛根，大青龙汤因内热烦躁而加石膏，小青龙汤以干呕而咳，而加半夏、细辛、干姜，麻黄附子细辛甘草二方，以脉沉而加附子，若连翘赤豆梓皮，湿热发黄而加。诸方剂皆因表实，从麻黄汤加减，何得独推大青龙为鼎立耶？何但知有风寒，而不知有风热，但知有中风见寒、伤寒见风的症，而不知小青龙汤治风寒、大青龙汤治风热、麻杏甘膏汤治温热、麻翘豆汤治湿热，表实中更有如是之别耶？且前辈之凿分风寒者，拘于脉耳。不知道张仲景论脉甚活而不拘，如大青龙汤的条，有中风而脉浮紧、伤寒而脉浮缓，是互文见意处。言中风脉缓，然亦有脉浮紧者；伤寒脉紧，然亦有脉浮缓者。大概中风伤寒，各有浅深，或因人之强弱而异，地之高下而异，时之乖和而异。证既不可拘，脉即不可执。如阳明中风而脉浮紧，太阴伤寒而脉浮缓，不可谓脉紧必伤寒，脉缓必中风矣。按《内经》脉滑曰风，则风脉原无定象；又盛而紧曰胀，则紧脉不专属伤寒；又缓而滑为热中，则缓脉亦不专指中风矣。且阳明中风，有脉浮而紧者，又有脉弦浮大者。必欲以太阳之脉缓自汗、脉紧无汗，定分风寒，割裂营卫，他经皆有中风，皆不言及何耶？要知道脉紧固为有力，脉浮缓也不是浮弱，即《内经》缓而滑为热中之脉也。大概张仲景凭脉辨证，只审虚实。所以不论中风伤寒脉之缓紧，但于指下有力者为实，脉弱无力者为虚；不汗出而烦躁者为实，汗出多而烦躁者为虚；证在太阳而烦躁者为实，证在少阴而烦躁者为虚。实者可服大青龙，虚者便不可服，这是最容易知道的。凡先烦不躁而脉浮者，必有汗而自解；烦躁而脉浮紧者，必无汗而不解。大青龙汤为风寒在表而兼热中者设，不是为有表无里而设。所以中风无汗烦躁者可用，伤寒而无汗烦躁者也可用。大概风寒本是一气，所以汤剂可以互投。论中有中风伤寒互称者，如大青龙汤是也；有中风伤寒兼提者，如小柴胡汤是也。张仲景只是仔细辨别脉症而施治，何曾拘拘于中风伤寒的区别其名乎？如既立麻黄汤治寒，桂枝汤治风，而中风见寒、伤寒见风者，为何不用桂枝麻黄各半汤，而更用大青龙汤为主治耶？且既有中风恶风不恶寒，伤寒恶寒不恶风之说，为何不用大青龙汤之恶寒主伤寒，麻黄证之恶风主中风，桂枝证之恶风复恶寒，主中风见寒、伤寒见风耶？方氏因三纲之分，而有风寒多少之陋见。喻嘉言又因大青龙之名，而为龙背龙腹龙尾之奇说。又谓纵横者，龙之所以飞期门及大青龙之位。青龙之说愈工，而青龙之法愈湮，此所谓好龙而不识真龙者也。大青龙汤的点睛，在无汗烦躁、无少阴证二句。合观之，知本方本为太阳烦躁而设。张仲景恐人误用青龙；不特为脉弱汗出者禁，而吃紧尤在少阴。大概少阴也有发热、恶寒、身疼、无汗而烦躁的症状，此阴极似阳，寒极反见热化也。误用则厥逆筋惕肉瞤所必至，全在此处着眼，所以必须审察其非少阴证，而为太阳烦躁无疑。太阳烦躁为阳盛，非大青龙汤不解。
Taiyang (Sun Yang) governs the exterior, therefore prescriptions for it primarily focus on releasing the exterior. However, within this release of the exterior, there is also concurrent treatment of the interior, resulting in a variety of different formulas. Mahuang Tang (Ephedra Decoction) descends rebellious Qi while releasing the exterior; Guizhi Tang (Cinnamon Twig Decoction) nourishes Yin while releasing the exterior; Gegen Tang (Kudzu Root Decoction) generates fluids while releasing the exterior; Da Qinglong Tang (Major Blue Green Dragon Decoction), Ma Xing Gan Shi Tang (Ephedra, Apricot Kernel, Licorice, and Gypsum Decoction), and Ma Lian Qiao Chi Dou Tang (Ephedra, Forsythia, and Adzuki Bean Decoction) clear fire while releasing the exterior; Xiao Qinglong Tang (Minor Blue Green Dragon Decoction) and Wuling San (Five-Ling Powder) promote diuresis while releasing the exterior. There are degrees of lightness and heaviness in clearing fire, and depths in promoting diuresis. As for Baihu Tang (White Tiger Decoction) clearing fire and Shizao Tang (Ten Jujube Decoction) promoting diuresis, these are treatments for conditions after the exterior has been resolved. The formulas such as Xuanxiong Tang (Chest-Draining Decoction), Xiexin Tang (Heart-Draining Decoction), Didang Tang (Visit the Palace Decoction), Tiaoweichengqi Tang (Regulate the Stomach and Purge Accumulation Decoction), Sini Tang (Reverse Cold Decoction), and Zhenwu Tang (True Warrior Decoction) are methods to rescue deviation according to symptoms. Generally speaking, diseases of the Taiyang exterior do not depart from the modifications of Guizhi Tang and Mahuang Tang, because the Heart is the interior of Taiyang. Now, I will discuss these formulas in detail to highlight Zhang Zhongjing’s therapeutic methods, allowing future generations to use them boldly. Thus, sayings such as "Mahuang Tang treats Shanghan (Cold Damage) but not Fengzhong (Wind Strike), and Guizhi Tang treats Fengzhong but not Shanghan" can be somewhat silenced.
Guizhi Tang:
Guizhi (Cinnamon Twig), Shaoyao (Peony Root), Gancao (Licorice Root), Shengjiang (Fresh Ginger), Dazao (Jujube Fruit)
This is the leader among Zhang Zhongjing’s group of formulas. It is the general formula for nourishing Yin and harmonizing Yang, harmonizing Ying (Nutritive) and Wei (Defensive), releasing the muscle layer, and inducing sweating. For any patient with headache, fever, aversion to wind or cold, with a floating and weak pulse, and spontaneous sweating, regardless of which meridian is involved, and whether it is Fengzhong, Shanghan, or miscellaneous diseases, this formula should be used to induce sweating. If improper sweating or purging was performed and the exterior condition remains unresolved, this formula should still be used to release the muscle layer. Regarding symptoms such as headache, fever, aversion to cold, aversion to wind, nasal congestion with roaring, and dry vomiting, if even one symptom is present, it is sufficient; they need not all be present. The primary indicators are a weak pulse and spontaneous sweating. Guizhi is red in color, enters the Heart, warms the meridians, and can support Yang to scatter cold. Its sweet taste benefits Qi and generates Blood; its pungent taste disperses external pathogens. Internally, it assists the Sovereign (Heart), stimulates Heart fluids to become sweat. Therefore, in formulas like Mahuang, Gegen, and Qinglong that induce sweating to ward off cold, Guizhi is always used. However, Guizhi Tang must not contain Mahuang, and Mahuang Tang cannot lack Guizhi. This formula consists mainly of pungent and sweet dispersing agents. Only Shaoyao is slightly bitter and slightly cold, capable of benefiting Yin and astringing Blood, and internally harmonizing Ying Qi. Ancestors stated that those without sweating cannot use Guizhi Tang because Shaoyao can stop sweating. The function of Shaoyao is originally to stop irritability; when irritability stops, sweating also stops. Therefore, cases of reversed irritability, increased irritability, palpitations with irritability, all rely on it. If the dosage of Shaoyao is doubled, it becomes a Jianzhong (Establish the Middle) type formula, not a formula for re-inducing sweating. In this formula, Guizhi induces sweating, while Shaoyao stops sweating. The pungency of Shengjiang assists Guizhi in releasing the muscle layer; the sweetness of Dazao assists Shaoyao in harmonizing the interior. Guizhi and Shaoyao complement each other; Shengjiang and Dazao are in harmony. Yin and Yang, interior and exterior, proceed together without contradiction; this is achieving harmony through the mutual assistance of rigid and soft properties. Gancao is sweet and neutral, possessing the power to secure the interior and repel the exterior. It is used to harmonize Qi and Blood, which is essentially harmonizing the interior and exterior, and also to harmonize the various herbs. The essence lies particularly in drinking hot thin porridge to assist the medicinal power. When grain Qi is充盈 (full) inside, external pathogens cannot enter again. Drinking hot porridge after taking the medicine ensures residual pathogens do not remain. This is another subtle use of compound formulas. Thus, using it to induce sweating will not lead to loss of Yang; using it to stop sweating will not leave behind trouble. Nowadays, whenever people encounter fever, regardless of deficiency or excess, they avoid grain foods. Those who publish Guizhi Tang formulas delete this method of drinking porridge. How could they understand Zhang Zhongjing’s core principles? One must know that this formula specifically treats exterior deficiency. It can only release the muscle layer and induce sweating from the Ying level; it cannot open the pores to expel pathogens from the Wei level. Therefore, if there is no sweating, it is a Mahuang Tang syndrome; if the pulse is floating and tight, it is a Mahuang Tang pulse, and Guizhi Tang should not be used. However, at the onset with no sweating, Mahuang Tang should be used to induce sweating. If irritability recurs after sweating, even if the pulse is floating and rapid, Mahuang Tang should not be given again; instead, Guizhi Tang should be used. If the disease does not resolve after sweating, or if the pulse remains floating after purging, with Qi rushing upward, or if diarrhea stops but body pain persists, this formula should be used to release the exterior. At this time, although the exterior is not resolved, the cou li (pores/skin texture) have loosened, and the pathogen is no longer in the skin and hair but in the muscles. Therefore, although the pulse and symptoms may resemble Mahuang Tang, the treatment belongs to Guizhi Tang. Unskilled physicians wrongly claim that Guizhi Tang exclusively treats Fengzhong, binding the eyes and ears of later generations. Moreover, the "Fengzhong" they describe does not match this formula, so they discard it. I often use this decoction to treat spontaneous sweating, night sweating, deficiency malaria, and deficiency dysentery, curing them readily. From this, I know that Zhang Zhongjing’s formulas can treat hundreds of diseases. Can this be compared to later generations’ categorization of syndromes that leaves practitioners with nowhere to start?
Mahuang Tang:
Mahuang (Ephedra Herb), Guizhi (Cinnamon Twig), Xingren (Apricot Kernel), Gancao (Licorice Root)
It treats Wind-Cold in the exterior, causing headache and stiff neck, fever and body pain, lower back pain, severe bone joint pain, aversion to wind and cold, absence of sweating, chest fullness with wheezing, with a floating-tight or floating-rapid pulse. This is a potent formula for opening the exterior, driving out pathogens, and inducing sweating. Ancient doctors used the principle of image-based medication. Mahuang is hollow inside and straight outside, resembling hair follicles and bone joints, thus it can remove Wind-Cold from the joints and expel it through the pores. It is a herb for the Wei level to disperse Wind-Cold. Guizhi branches crisscross, resembling meridians and collaterals; it enters the Heart to transform fluids, unblocks meridians to induce sweating, and is a herb for the Ying level to resolve Wind-Cold. Xingren is a fruit of the Heart; its warmth assists the Heart in scattering cold, and its bitterness clears the Lung and directs Qi downward. It is a herb for the Upper Jiao to drive out pathogens and calm wheezing. Gancao is sweet and neutral, repelling Wind-Cold externally and harmonizing Qi and Blood internally. It is a herb for the Central Jiao to secure the interior and repel the exterior. This decoction, upon entering the stomach, circulates Qi through the xuanfu (pores), and transmits essence to the skin and hair. When hair and vessels combine their essence, profuse sweating occurs. Pathogens in the exterior are completely eliminated without leaving residue. Pain stops, wheezing calms, and chills and fever resolve instantly. There is no need to drink porridge to borrow grain Qi for sweating. It does not use Shengjiang and Dazao because Shengjiang’s nature spreads horizontally to release the muscle layer, hindering Mahuang’s ascending action; Dazao’s nature is sticky and obstructs the diaphragm, hindering Xingren’s rapid descent. This is to achieve rapid direct action; if slowed, it is not swift; if spread horizontally, it is not potent. If the pulse is floating-weak with spontaneous sweating, or if the chi (cun-guan-chi) pulse is faint and slow, this is indicated for Guizhi Tang, not suitable for this formula. This is a pure Yang formula, overly dispersing, like a general charging straight ahead. If applied correctly, victory is achieved in one battle; if incorrect, failure brings disaster. Therefore, when using it to release the exterior, it can be used once but not repeatedly. If the disease does not resolve after sweating, it should be replaced by Guizhi Tang. If sweating is incomplete and pathogens linger between skin, hair, bones, and muscles, there are the ingenious uses of Mahui Banxia Tang (Half-Ephedra Half-Cinnamon Twig Decoction) and Guizhi Er Mahuang Yi Tang (Two-Parts Cinnamon Twig One-Part Ephedra Decoction). If Yang is excessive internally with no sweating, there are formulas like Mahuang Xingren Shigao Lianqiao Chidou Tang. These are all Zhang Zhongjing’s core methods. I treat cold-wind asthma and bi-syndrome caused by the combination of Wind, Cold, and Dampness with this formula, and it is often effective. It is not limited to Shanghan alone. Note: Regarding Mahuang and Guizhi formulas treating Shanghan and Fengzhong, practitioners hesitate to use them when appropriate, while commentators wrongly claim they are appropriate when they are not. For example, the statement "Taiyang nosebleed syndrome should use Guizhi Tang" implies that sweating or purging is required at that juncture. The phrase "Mahuang zhu zhi" (Mahuang Tang governs it) implies inducing sweating or purging. These two phrases are added at the end as a reverse order technique. Zhang Zhongjing explains the rationale in detail during syndrome differentiation but does not mention the formula yet. Guizhi promotes blood circulation. Zhang Zhongjing uses Guizhi to induce sweating, not to stop nosebleeds. It is used before bleeding occurs, not after. Moreover, those who lose blood cannot sweat; this logic is clear. Mahuang is an ascending herb. Since it is said that nosebleed leads to resolution, and spontaneous nosebleed leads to healing, reusing an ascending drug would inevitably cause continuous bleeding. Furthermore, those with chronic nosebleeds cannot undergo sweating therapy; this prohibition is very clear. Similarly, the phrase "Xiao Qinglong zhu zhi" implies after taking the medicine. Would one use a drying-hot formula when cold has gone and resolution is desired, thereby destroying fluids and causing unquenchable thirst? And what medicine is referred to by "after taking medicine"? Observe that Zhang Zhongjing explicitly criticizes inappropriate medications, such as "After taking Xiexin Tang, purged with another medicine, diarrhea did not stop," or "Knowing the doctor purged with another medicine, this was not the correct treatment." Unskilled doctors do not understand reverse order techniques and are obsessed with the terms Wind and Cold, claiming that even with severe heat, since the pathogen is in the meridian, using Mahuang for nosebleed is merely dispersing meridian pathogens. Ask yourself: Is the pathogen Cold or Heat? If Cold, blood coagulates and does not flow, how can there be nosebleed? If Heat, one should clear and descend urgently, how dare one ascend and disperse? Also, it is said that if bleeding is scanty, medication is necessary. If it flows continuously, what method is used to manage it afterwards? This error harms the common people the most. I hereby expose and clarify it.
Gegen Tang:
Gegen (Kudzu Root), Mahuang (Ephedra Herb), Guizhi (Cinnamon Twig), Baishao (White Peony Root), Gancao (Licorice Root), Jiang (Ginger), Zao (Jujube)
It treats stiffness and pain in the head and neck, stiffness in the back, pulling sensations, floating pulse, absence of sweating, and aversion to cold. It also treats self-directed diarrhea due to Wind-Cold in the exterior. This is a mild formula for opening the exterior and driving out pathogens. The symptoms include no body pain, no lower back pain, no joint pain, indicating the bones are not affected by Cold. Head and neck stiffness extending to the back with pulling discomfort indicates tendons injured by Wind. No wheezing, no irritability, no dry vomiting indicates no internal syndrome. Absence of sweating and aversion to wind indicates the disease is solely in the exterior. If exterior disease is accompanied by diarrhea, it is Exterior Excess and Interior Deficiency. It is milder than Mahuang Tang and Qinglong Tang formulas. However, the neck-back stiffness is more severe than simple neck stiffness. Absence of sweating still constitutes Exterior Excess. The pulse is floating but not tight or rapid, indicating invasion by the moving Yang-Wind. Therefore, Guizhi Tang is the base, with added Mahuang and Gegen to attack the Exterior Excess. Gegen is sweet and cool in nature. It raises Yin Qi and generates fluids, nourishes tendons and meridians, and relieves pulling. Thus, it serves as the Sovereign herb. Mahuang and Shengjiang open the closure of xuanfu and cou li, dispel Wind, and induce sweating, serving as Minister herbs. Since both Cold and Heat are mild, small amounts of Guizhi and Shaoyao are added, along with Gancao and Dazao, to harmonize the interior. This formula balances the weight between Mahuang and Guizhi formulas, serving as a formula to harmonize the exterior and interior. Thus, when used for Exterior Excess, external pathogens resolve naturally. There is no need to treat Interior Deficiency directly, and diarrhea heals itself. This differs from Da Qinglong Tang, which treats simultaneous Exterior and Interior Excess. One must know that Gegen has a light and clear nature but a heavy substance. Lightness can remove excess; heaviness can calm agitation; density can secure the interior. It possesses three virtues in one herb. However, it is only suitable for Exterior Excess and Interior Deficiency. It is not suitable for Stomach Excess. Therefore, Zhang Zhongjing does not use Gegen in the Yangming Meridian chapter. Li Dongyuan categorized herbs by meridian, placing Gegen in Yangming rather than Taiyang. Yi Lao said, "Do not take if it has not entered Yangming." Both fail to understand this meaning. Yu Jia Yan claimed "Zhang Zhongjing does not use it in Yangming to prevent fluid loss," which contradicts the Ben Cao (Materia Medica) saying it generates fluids. He also claimed it "opens the muscle layer," contradicting Zhang Zhongjing’s addition of Gegen to Guizhi Tang for sweating and aversion to wind. Essentially, both Guizhi and Gegen are formulas that release the muscle layer and harmonize the interior. Therefore, they can be used whether there is sweating or not, and whether there is diarrhea or not. This differs from Mahuang, which specializes in treating the exterior. Both Mahuang and Gegen have foam when boiled; foam represents turbid Qi. Therefore, Zhang Zhongjing boils them first to remove the foam before adding other herbs. This takes advantage of their clear and ascending nature to open the cou li. The reason for drinking thin porridge with Guizhi Tang is that without Mahuang’s opening power, there is Shaoyao’s astringent power. Fearing pathogens may not be fully expelled, grain Qi is borrowed to drive them out. This is where sweat is born from grain.
Da Qinglong Tang:
Mahuang (Ephedra Herb), Guizhi (Cinnamon Twig), Shigao (Gypsum Fibrosum), Xingren (Apricot Kernel), Gancao (Licorice Root), Jiang (Ginger), Zao (Jujube)
Taiyang Fengzhong, with a floating-tight pulse, headache, fever, aversion to cold, body pain, absence of sweating, and irritability. This is a severe form of the Mahuang Tang syndrome, hence modified to treat it. All symptoms are those of Mahuang Tang, distinguished by wheezing versus irritability. Wheezing is caused by Cold stagnating Qi, preventing free ascent and descent, so a larger amount of bitter Xingren is used to direct Qi downward. Irritability is caused by Heat damaging Qi and lacking fluids to produce sweat, so specific addition of sweet Shigao is used to generate fluids. However, Shigao is heavy and extremely cold. Fearing that internal heat is suddenly cleared while exterior Cold remains unresolved, leading to Cold in the Middle with accompanying heat-induced diarrhea (inviting the thief to break into the house), one must double the dose of Mahuang to release the exterior, double Gancao to harmonize the Middle, and use Jiang and Zao to regulate Ying and Wei. A single sweat resolves both interior and exterior, eliminating both Wind and Heat. This demonstrates Da Qinglong Tang’s power to clear the interior and repel the exterior, supplementing the deficiencies of Mahuang and Guizhi formulas. The name Qinglong (Blue Green Dragon) refers to inducing sweating. The distinction between Large and Small Qinglong lies in the amount of Mahuang, not Shigao, as seen in Xiao Qinglong Tang which does not use Shigao. Shigao cannot驱散 (dispel) Wind-Cold in the exterior; it only clears blazing heat in the Middle Jiao, as seen in the frequent use of Baihu Tang. People today do not know that Shigao is for irritability, mistakenly thinking it is for inducing sweating. The "Light can remove Excess" category in the Ten Formulas—how can a substance of extreme hardness and weight induce sweating? The error of excessive sweating leading to loss of Yang lies with Mahuang. Shaoyin (Lesser Yin) also presents with fever, aversion to cold, and irritability, similar to Da Qinglong Tang, but differs in that the pulse is not floating and the head does not hurt. If the pulse is floating-weak with spontaneous sweating, it is a Guizhi syndrome. Using Shigao recklessly in these cases prevents Stomach Qi from reaching the limbs, causing cold hands and feet. Using Mahuang recklessly prevents Wei Yang from circulating the body, causing muscle twitching. These are deeply cautioned against by Zhang Zhongjing. One must know that if Shaoyin presents with Yang symptoms and Mahuang is used, it must be secured with Fuzi (Aconite Root). Taiyang and Shaoyin occupy different positions and follow different paths of Yin and Yang, so Cold and Warmth therapies differ. The irritability in Guizhi syndrome stems from Wood hyperactivity, treated with slightly bitter and slightly cold agents to regulate ascent and descent. The restlessness accompanying irritability in Da Qinglong Tang stems from Wind agitation, treated with extremely Yin and heavy substances to suppress it. Presence or absence of sweating, deficiency or excess, determine the severity. One must carefully examine what is contraindicated to ensure correct usage.
Note: Xu Shuwei said, "Guizhi treats Fengzhong, Mahuang treats Shanghan, Da Qinglong treats Fengzhong presenting with Han pulse, and Shanghan presenting with Feng pulse. The three stand like a tripod." This is the origin of Fang’s Three Major Principles. Consequently, the syndrome and treatment of Da Qinglong Tang became unclear in the world. One does not realize that Zhang Zhongjing’s treatment of the exterior relies only on Mahuang and Guizhi methods. Mahuang treats Exterior Excess; Guizhi treats Exterior Deficiency. Formula application is divided by Excess and Deficiency, not by Wind and Cold. Both Wind and Cold syndromes have Excess and Deficiency, depth and shallowness, and involve Ying and Wei. The major principle divides depth and shallowness by Excess and Deficiency, not by Ying and Wei of Wind and Cold. Sweating indicates Exterior Deficiency; Guizhi Tang is established to treat Wind-Cold with sweating. Modifications include adding/removing Guizhi, adding/removing Shaoyao, and adding Fuzi, Renshen, Houpo, Xingren, Fuling, Baizhu, Dahuang, Longgu, Muli, etc. These are all variations of Guizhi Tang. Because Interior Deficiency and Excess vary in depth within Exterior Deficiency, modification methods vary greatly. Absence of sweating indicates Exterior Excess; Mahuang Tang is established to treat Wind-Cold without sweating. However, Exterior Excess may also involve夹杂 (mixing) Cold/Summerheat, Internal Cold/Internal Heat. Thus, based on Mahuang, modifications include Gegen Tang, Large/Small Qinglong Tang, Mahuang Fuxi Xixin Gancao Tang, Mahuang Xingren Gancao Shigao Tang, Ma Lian Qiao Chi Dou Tang, etc. These are all variations of Mahuang Tang. Because Exterior Excess varies in Internal/External Cold/Heat depth. Gegen Tang adds Shaoyao and Gegen due to insufficient muscle fluids; Da Qinglong Tang adds Shigao due to internal heat and irritability; Xiao Qinglong Tang adds Banxia, Xixin, Ganjiang due to dry retching and coughing; Mahuang Fuxi Xixin Gancao Tang adds Fuzi due to deep pulse; Lianqiao Chidou Zibi is added for damp-heat jaundice. All these formulas are based on Exterior Excess and modified from Mahuang Tang. Why single out Da Qinglong Tang as standing apart? Why only know of Wind-Cold and not Wind-Heat? Why only know of Fengzhong with Han pulse and Shanghan with Feng pulse, and not know that Xiao Qinglong Tang treats Wind-Cold, Da Qinglong Tang treats Wind-Heat, Ma Xing Gan Shi Tang treats Warm-Thermal, and Ma Qiao Dou Tang treats Damp-Heat, showing further distinctions within Exterior Excess? Moreover, ancestors who rigidly divided Wind and Cold were constrained by pulse diagnosis. They did not know Zhang Zhongjing’s pulse discussion is flexible. For example, in the Da Qinglong Tang clause, there is Fengzhong with floating-tight pulse and Shanghan with floating-slow pulse. This is intertextual implication. It means Fengzhong usually has a slow pulse, but can have a floating-tight one; Shanghan usually has a tight pulse, but can have a floating-slow one. Fengzhong and Shanghan have varying depths, differing by individual strength, geographical altitude, and seasonal harmony. Since syndromes cannot be rigidly defined, pulses cannot be dogmatically held. For instance, Yangming Fengzhong can have a floating-tight pulse, and Taiyin Shanghan can have a floating-slow pulse. One cannot say tight pulse must be Shanghan and slow pulse must be Fengzhong. According to Nei Jing, a slippery pulse indicates Wind, so Wind pulse has no fixed image. A full and tight pulse indicates distension, so tight pulse is not exclusive to Shanghan. A slow and slippery pulse indicates internal heat, so slow pulse does not exclusively refer to Fengzhong. Furthermore, Yangming Fengzhong can have a floating-tight pulse or a string-like, floating, large pulse. Insisting on dividing Wind and Cold by Taiyang’s slow-pulse-with-sweating and tight-pulse-without-sweating splits Ying and Wei arbitrarily. Other meridians also have Fengzhong, why are they not mentioned? One must know that a tight pulse is definitely forceful, and a floating-slow pulse is not necessarily floating-weak; it corresponds to the Nei Jing’s slow-and-slippery pulse for internal heat. Zhang Zhongjing diagnoses based on pulse and syndrome, focusing only on Excess and Deficiency. Therefore, regardless of whether the pulse is slow or tight in Fengzhong or Shanghan, forceful under the fingers indicates Excess; weak and powerless indicates Deficiency. No sweating with irritability indicates Excess; profuse sweating with irritability indicates Deficiency. Irritability in Taiyang indicates Excess; irritability in Shaoyin indicates Deficiency. Excess can take Da Qinglong Tang; Deficiency cannot. This is easy to understand. Those who are irritable but not restless with a floating pulse will likely sweat and resolve spontaneously. Those who are irritable and restless with a floating-tight pulse will likely have no sweating and not resolve. Da Qinglong Tang is designed for Wind-Cold in the exterior combined with internal heat. It is not designed for exterior-only conditions. Therefore, it can be used for Fengzhong without sweating and irritability, and for Shanghan without sweating and irritability. Wind and Cold are fundamentally one Qi, so the decoctions can be interchangeable. The text mentions Fengzhong and Shanghan interchangeably, such as in Da Qinglong Tang; and jointly, such as in Xiao Chaihu Tang. Zhang Zhongjing simply differentiates pulse and syndrome to apply treatment. Did he ever rigidly distinguish the names Fengzhong and Shanghan? If Mahuang Tang treats Cold and Guizhi Tang treats Wind, why not use Guizhi Mahuang Banxia Tang for Fengzhong with Cold signs and Shanghan with Wind signs, but instead use Da Qinglong Tang as the main treatment? Furthermore, if there is a theory that Fengzhong involves aversion to wind but not cold, and Shanghan involves aversion to cold but not wind, why not assign Da Qinglong Tang’s aversion to cold to Shanghan, Mahuang syndrome’s aversion to wind to Fengzhong, and Guizhi syndrome’s aversion to wind and cold to Fengzhong with Cold/Shanghan with Wind? Fang Shi had a crude view of Wind-Cold proportions due to the Three Principles division. Yu Jia Yan created bizarre theories about dragon backs, bellies, and tails due to the name Da Qinglong Tang. He claimed the crisscrossing refers to the dragon’s flight position at Qimen and Da Qinglong. The more intricate the Dragon theory, the more obscured the Dragon method. This is called loving dragons but not knowing the true dragon. The key points of Da Qinglong Tang are "no sweating with irritability" and "no Shaoyin syndrome." Viewing them together, this formula is originally set for Taiyang irritability. Zhang Zhongjing fears people will misuse Qinglong; he not only prohibits it for those with weak pulses and sweating, but emphasizes especially Shaoyin. Shaoyin also presents with fever, aversion to cold, body pain, no sweating, and irritability. This is Extreme Yin resembling Yang, Extreme Cold manifesting as Heat transformation. Misuse will inevitably lead to reversal cold, limb cold, and muscle twitching. The crucial point lies here. One must ascertain it is not a Shaoyin syndrome, confirming it is undoubtedly Taiyang irritability. Taiyang irritability is Yang Excess, which cannot be resolved without Da Qinglong Tang.