伤寒有六经之证，有六经之脉，证脉井然不杂，则可直指为某经之病。若两经、三经
，阴阳混淆，不可以一经名者；或一经未罢又传一经，二经、三经同病，不归并一经
者，则名曰合病。或二经、三经同病，其后归并一经自病者，则名曰并病。论中所着
合病、并病，虽单举阳经，未及阴经，然阳经既有合病、并病，则阴经亦必有之可知
矣。如太阳病脉反沉，少阴病反发热，是少阴、太阳合病也；阳明病脉迟，太阴病大
实痛，是太阴、阳明合病也；少阳病脉细而厥，厥阴病呕而发热，是厥阴、少阳合病
也。是虽无合病之名，而确有合病之实。且三阳皆有发热证，三阴皆有下利证，如发
热而下利，是阴阳合病也，阴阳合病，若阳盛者属阳经，则下利为实热，即论中所谓
太阳、阳明，阳明、少阳，太阳、少阳，合病者是也。阴盛者属阴经，则下利为虚寒
，即论中所谓少阴下利反发热不死，少阴下利清谷，里寒外热，不恶寒而面赤者是也
。盖阳与阳合，不合于阴，为三阳合病，则不下利而自汗出，乃白虎汤证也；阴与阴
合，不合于阳，为三阴合病，则不发热而吐利厥逆，乃四逆汤证也。诚以人之藏府互
根，阴阳相合，三阳既有合并之病，则三阴亦有合并之病，不待言矣。
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太阳与阳明合病者，必自下利，葛根汤主之。太阳与阳明合病，不下利，但呕者，葛
根加半夏汤主之。
【注】
一经未罢，又传一经、二经、三经同病，而不归并一经者，谓之合病。太阳与阳明合
病者，谓太阳之发热，恶寒无汗，与阳明之烦热不得眠等证，同时均病。表里之气，
升降失常，故不下利，则上呕也。治法只须先解太阳之表，表解而阳明之里自和矣。
若利则宜葛根汤表而升之，利自可止；呕则加半夏，表而降之，呕自可除也。
【集注】
成无己曰：邪气外盛，阳不主里，则里气不和。里气下而不上者，但利而不呕；里气
上逆而不下者，但呕而不利，故以葛根汤以散表邪，加半夏以下逆气也。
伤寒病有六经的证候，也有六经的脉象。如果证候与脉象条理清晰、互不混杂，就可以直接指明为某一经的病证。如果有两经或三经的病证同时出现，阴阳混淆，不能用单一经名来概括；或者一经的病证尚未痊愈，又传变至另一经，导致二经、三经同时患病，不归并于单一经的情况，就称为“合病”。如果是二经、三经同时患病，随后病邪归并到一经而单独发病的情况，就称为“并病”。《伤寒论》中论述的合病、并病，虽然只列举了阳经，未涉及阴经，但既然阳经存在合病、并病，那么阴经也必然存在，这是可以推知的。例如：太阳病脉象反而沉细，少阴病反而发热，这是少阴与太阳的合病；阳明病脉象迟缓，太阴病出现大实痛，这是太阴与阳明的合病；少阳病脉象细弱且四肢厥冷，厥阴病呕吐且发热，这是厥阴与少阳的合病。这些情况虽然没有明确冠以“合病”之名，但确实具有合病的实质。而且三阳经都有发热的证候，三阴经都有下利的证候。如既有发热又有下利，这就是阴阳合病。阴阳合病中，若阳气偏盛归属于阳经，则下利属于实热，即《伤寒论》中所说的太阳与阳明合病、阳明与少阳合病、太阳与少阳合病等情况。若阴气偏盛归属于阴经，则下利属于虚寒，即《伤寒论》中所说的少阴病下利反而发热者不死、少阴病下利清谷（排出未消化的食物）、里有寒气外有假热、不恶寒而面部发红等情况。一般来说，阳与阳相合，不与阴相合，称为三阳合病，则不会出现下利而是自汗出，这属于白虎汤证的范畴；阴与阴相合，不与阳相合，称为三阴合病，则不会发热而是出现呕吐、下利和四肢厥逆，这属于四逆汤证的范畴。诚然，人体的脏腑互为根本，阴阳相互依存，三阳经既然有合并的病证，那么三阴经也必然有合并的病证，这是不言而喻的。
太阳经与阳明经合病者，必定会出现自发性下利，用葛根汤主治。太阳经与阳明经合病，如果没有下利，只是呕吐的，用葛根加半夏汤主治。
【注】
一经的病证尚未罢止，又传变至另一经，导致二经、三经同时患病，而不归并于单一经的情况，称为合病。所谓太阳与阳明合病，是指太阳经的发热、恶寒、无汗等证候，与阳明经的烦热、不得睡眠等证候，同时发生。表里之气的升降功能失常，所以如果不出现下利，就会出现上逆呕吐的症状。治疗方法只需先解除太阳经的表邪，表邪解除后，阳明经的里气自然调和。如果出现下利，适宜用葛根汤通过发汗解表并升提清气的方法治疗，下利自然可以停止；如果出现呕吐，则加入半夏，通过发汗解表并降逆止呕的方法治疗，呕吐自然可以消除。
【集注】
成无己说：邪气在体表强盛，阳气不能固护于里，导致里气不和。里气向下而不向上逆的，只出现下利而不呕吐；里气向上逆而不向下的，只出现呕吐而下利，因此使用葛根汤来疏散表邪，加入半夏来降逆气。
Typhoid diseases manifest with the syndromes and pulses of the Six Channels. If the syndromes and pulses are distinct and non-mixed, one can directly identify it as a disease of a specific channel. However, if the syndromes of two or three channels appear simultaneously, causing a confusion of Yin and Yang that cannot be named by a single channel; or if a disease in one channel has not yet resolved before transmitting to another, resulting in simultaneous involvement of two or three channels without merging into one, this is termed "He Bing" (Combined Disease). If two or three channels are involved simultaneously, but subsequently the pathogen merges into a single channel where it manifests independently, this is termed "Bing Bing" (Consecutive Disease). Although the Treatise on Cold Damage discusses He Bing and Bing Bing primarily regarding the Yang channels without explicitly mentioning the Yin channels, since He Bing and Bing Bing exist in the Yang channels, it follows that they must also exist in the Yin channels. For instance, when Taiyang disease presents with a pulse that is unexpectedly deep, and Shaoyin disease presents with unexpected fever, this constitutes a combined disease of Shaoyin and Taiyang. When Yangming disease presents with a slow pulse, and Taiyin disease presents with severe pain due to excess, this constitutes a combined disease of Taiyin and Yangming. When Shaoyang disease presents with a fine pulse and cold extremities, and Jueyin disease presents with vomiting and fever, this constitutes a combined disease of Jueyin and Shaoyang. Although these cases may not bear the name "combined disease," they indeed possess the reality of combined disease. Furthermore, all Three Yang channels present with fever, and all Three Yin channels present with diarrhea. If both fever and diarrhea occur, this is a combined disease of Yin and Yang. In such Yin-Yang combined diseases, if Yang predominance aligns with the Yang channels, the diarrhea is due to excess-heat, corresponding to what the Treatise describes as combined diseases of Taiyang and Yangming, Yangming and Shaoyang, or Taiyang and Shaoyang. If Yin predominance aligns with the Yin channels, the diarrhea is due to deficiency-cold, corresponding to what the Treatise describes as Shaoyin diarrhea with unexpected fever (which is not fatal), Shaoyin diarrhea with undigested food, interior cold with exterior false heat, absence of aversion to cold, and redness of the face. Generally, when Yang combines with Yang, excluding Yin, it is called a combined disease of the Three Yang channels, characterized by spontaneous sweating rather than diarrhea, which falls under the syndrome of Baihu Tang (White Tiger Decoction). When Yin combines with Yin, excluding Yang, it is called a combined disease of the Three Yin channels, characterized by vomiting, diarrhea, and cold extremities without fever, which falls under the syndrome of Sini Tang (Frigid Extremities Decoction). Indeed, the Zang-Fu organs of the human body are mutually rooted, and Yin and Yang are interdependent. Since there are combined diseases in the Three Yang channels, it goes without saying that there are also combined diseases in the Three Yin channels.
When Taiyang and Yangming channels have a combined disease, spontaneous diarrhea will inevitably occur, treated primarily with Gegen Tang (Kudzu Root Decoction). When Taiyang and Yangming channels have a combined disease, if there is no diarrhea but only vomiting, it is treated primarily with Gegen Jia Banxia Tang (Kudzu Root plus Pinellia Decoction).
[Annotation]
When a disease in one channel has not yet resolved before transmitting to another, resulting in simultaneous involvement of two or three channels without merging into one, it is called He Bing (Combined Disease). The term "Taiyang and Yangming combined disease" refers to the simultaneous occurrence of symptoms such as fever, aversion to cold, and anhidrosis from the Taiyang channel, and symptoms such as irritability, heat, and insomnia from the Yangming channel. The ascending and descending functions of the Wei (Defensive) and Ying (Nutritive) Qi at the exterior and interior become disordered. Therefore, if diarrhea does not occur, upper reversal leads to vomiting. The treatment method requires first resolving the exterior syndrome of the Taiyang channel; once the exterior is resolved, the interior of the Yangming channel will naturally harmonize. If diarrhea occurs, Gegen Tang (Kudzu Root Decoction) should be used to release the exterior and ascend the clear Qi, which will stop the diarrhea. If vomiting occurs, Banxia (Pinelliae Rhizoma) should be added to release the exterior and descend the rebellious Qi, which will eliminate the vomiting.
[Collected Notes]
Cheng Wuji stated: When pathogenic factors are strong at the exterior, Yang fails to govern the interior, leading to disharmony of the interior Qi. When interior Qi descends without reversing upward, only diarrhea occurs without vomiting; when interior Qi reverses upward without descending, only vomiting occurs without diarrhea. Therefore, Gegen Tang (Kudzu Root Decoction) is used to dissipate exterior pathogens, and Banxia (Pinelliae Rhizoma) is added to direct rebellious Qi downward.