三阳合病下利。有热无寒。三阴下利。自利属寒。阳邪属热。太阳阳明合病。自下利者。此风邪入胃
也。脉浮而长。所见皆太阳症。以下利故。知与阳明合病也。用葛根汤表提风邪。利自止矣。
邵评∶下利有寒热之不同。三阳合病下利。邪化热而入里。无寒症也。三阴下利。
有直中传经二因。直中下利为寒。从阳经传入者。为热利也。太阳之邪。并入阳明而自下利。为太阳阳明合
病。合病下利者。里气得热而下行也。脉浮为太阳。长为阳明脉。见太阳症者。太阳之邪。初入阳明之里。
两阳合明。邪气火盛。表实里虚。故外见太阳症。而里则下利也。用葛根汤辛甘发散。以从阳解。两阳相合
之邪。下者举之之法也。且太阳阳明合病下利。是太阳症内陷阳明。故用表剂中加葛根。以清里热。
若桂枝症。误下而利不止。脉促者。表未解也。汗出而喘。当用葛根黄芩黄连汤。外
解表邪。内清里热。
邵评∶阳陷于内者十之七。留于表者十之三。故曰表未解也。邪束于表。阳扰于内。故喘而汗出。
表里俱病。用葛根之辛凉以解表。用芩连之苦寒以清里也。
太阳少阳合病自下利者。黄芩汤。此热邪已入少阳之里。胆火大炽。移热于脾。故
自下利。脉浮而弦。外症必头痛胸满。口苦咽干目眩。或往来寒热。热邪不在半表
而在半里。故不用柴胡而主黄芩。呕加半夏、生姜。治痰饮也。
邵评∶少阳半表半里。比阳明为尤深。邪热更易内侵太少。两阳合病。阳盛阴虚。
阳气下陷入阴中。故自下利。而治法与阳明不同矣。太阳阳明合病。其邪初入阳明之表。邪近于外。
故用葛根驱邪。使从外出为顺。太阳少阳合病。是邪已入少阳之里。邪入于内。故用黄芩治之。使从内出
为易。夫热淫于内。黄芩之苦以清之。肠胃得热而不固。芍药之酸。甘草之甘。以收固之。酸苦涌泄
为阴。亦通因通用之法也。若呕者。热邪上逆也。故加半夏、生姜以散逆气。而黄芩之清里。亦
法之所不易矣。且黄芩汤。小柴胡加减方也。热不在半表。已入半里。故以黄芩清里。虽非胃实。亦非
胃虚。故不须人参补中也。
或云。此少阳指三焦。不指胆。
少阳阳明合病。自下利者。其脉不负者顺也。负者失也。滑而数者。有宿食也。当下之。如发热呕恶。
心下痞硬。或往来寒热。大柴胡汤主之。（阳明脉胜则洪缓为不负而顺少阳脉胜则弦紧为负而逆）
按三阳合病下利。惟少阳阳明为重。土受木克也。故阳明脉胜为顺。阳明脉负为失。失者死也。
（注释参来苏集）
三阴下利。俱详见本病下。如腹满而痛。吐利交作。或下利清谷。吐利四逆。或下利
身重。小便不利等症。皆属三阴本脏虚寒。当以理中、四逆、真武辈治之。
邵评∶此三阴自受寒邪而下利之正法。
三阴热邪下利。太阴有暴烦下利。腹满大痛。咽干而渴之症。少阴有自利清水。色
纯青。心下痛口干燥之症。俱是转属阳明。宜承气辈主之。少阴又有四逆。泄利下重。小便不利。腹中痛之症。
亦属热邪。宜四逆散。厥阴热利下重。渴欲饮水。脉弦而数。此风木热邪乘脾。白头翁汤主之。
邵评∶阳经热邪。传入太阴。热灼津伤。转属阳明。而成胃实见症。皆热实之象。故
可用下法。若少阴热并阳明之症。少阴经中热极。则迫其水下流。而肾水燥。燥则肠中之物更坚。故利清
水。色纯青者。肾弱而肝反侮之也。心下痛为实。口干燥为热。用大承气急下燥屎以存津也。至于四
逆。四肢逆冷也。阳气不达于四肢。故逆冷。泄利下重。是阳邪下陷入阴。阳内而阴反外。阴阳脉气
不顺接也。小便不利腹痛。水气为患也。用四逆散和解表里之邪。惟热邪传入厥阴。为协热下利。热利下
重。乃湿热秽气郁遏于下焦广肠。故魄门重滞。虽利而难出也。渴欲饮水者。以里有热。传经之邪。
厥阴受之也。弦为肝脉。数则里热也。用白头翁辛淡以除邪气。连柏苦寒以清热。秦皮苦凉性涩。入厥
阴而止利也。
又评∶少阴四逆者。四肢厥冷也。此非热厥。乃太阳初受寒邪。便入少阴之症。少阴为阴枢。邪气居
之。可进可退。故其病每多或然之症。因取四味以散四逆之邪。此少阴气分之下剂也。
凡厥阴病。先发厥。后发热。不退者。必便脓血也。脉数有力。从阳治。脉沉无力。从阴治。
邵评∶热不退者。阳邪盛也。阳盛则伤阴络。故知必便脓血也。便血而脉数有力
者。宜滋阴清热。从阳治之。脉沉无力者。当温中和营。从阴治之。
三阳经同时受邪导致的下利，表现为有热象而无寒象。三阴经受邪导致的下利，自发性下利属于寒证。阳邪性质属热。太阳与阳明两经合病，出现自发性下利的，这是风邪侵入胃腑的表现。脉象浮而长，所见的症状都是太阳病的表现，因为伴有下利，所以知道是与阳明合病。使用葛根汤（Ge Gen Tang, Pueraria Decoction）从表发散风邪，下利自然停止。
邵评：下利有寒证和热证的不同。三阳合病导致的下利，邪气化热并深入体内，没有寒证表现。三阴下利，有直中（寒邪直接侵犯脏腑）和传经（由他经传入）两种原因。直中导致的下利为寒证，从阳经传入的则为热利。太阳之邪并入阳明而自发下利，称为太阳阳明合病。合病导致下利，是因为里气受热而下行。脉浮表示太阳病，脉长表示阳明病。见到太阳症状，说明太阳之邪初入阳明之里。两阳相合，阳气明盛，邪气火热炽盛，表现为表实里虚，所以外见太阳症状，而内部则出现下利。使用葛根汤辛甘发散，以顺应阳气解表。这是针对两阳相合之邪，采用“下者举之”（提升下陷之气）的方法。而且太阳阳明合病下利，是太阳症状内陷阳明，所以在解表剂中加入葛根，以清解里热。
如果是桂枝汤证（Gui Zhi Tang Syndrome），误用攻下法导致下利不止，脉象急促的，说明表邪未解。伴有出汗且气喘，应当使用葛根黄芩黄连汤（Ge Gen Huang Qin Huang Lian Tang, Pueraria, Scutellaria and Coptis Decoction）。外解表邪，内清里热。
邵评：阳气内陷的情况占十分之七，留滞在体表的情况占十分之三，所以说表邪未解。邪气束缚于体表，阳气扰动于内部，所以气喘且出汗。表里俱病，使用葛根的辛凉性质来解表，使用黄芩、黄连的苦寒性质来清里热。
太阳与少阳两经合病，自发下利的，使用黄芩汤（Huang Qin Tang, Scutellaria Decoction）。这是因为热邪已经深入少阳之里，胆火旺盛，热邪移于脾脏，所以自发下利。脉象浮而弦，外部症状必有头痛、胸满、口苦、咽干、目眩，或者往来寒热。热邪不在半表而在半里，所以不使用柴胡，而以黄芩为主药。呕吐的加半夏、生姜，治疗痰饮。
邵评：少阳位于半表半里，比阳明更深。邪热更容易内侵太阳和少阳。两阳合病，阳气盛而阴液虚，阳气下陷入阴中，所以自发下利，治疗方法与阳明不同。太阳阳明合病，邪气初入阳明之表，邪气靠近外部，所以用葛根驱邪，使邪气从外出为顺。太阳少阳合病，是邪气已入少阳之里，邪气进入内部，所以用黄芩治疗，使邪气从内出为易。热邪淫溢于内，用黄芩的苦味来清泄它。肠胃受热而不固摄，芍药的酸味、甘草的甘味，用来收敛固涩。酸苦涌泄属于阴法，这也是“通因通用”（用通利的方法治疗通泄的病证）的方法。如果呕吐，是热邪上逆，所以加半夏、生姜以散逆气，而黄芩清里热的作用也是不可改变的法度。而且黄芩汤是小柴胡汤（Xiao Chai Hu Tang, Minor Bupleurum Decoction）的加减方。热邪不在半表，已入半里，所以用黄芩清里热。虽然不是胃实（胃肠实热积滞），也不是胃虚，所以不需要人参补中益气。
有人说，这里的少阳指的是三焦，不指胆。
少阳与阳明两经合病，自发下利的，如果脉象不负（即阳明脉胜）为顺证；脉象负（即少阳脉胜）为逆证。脉滑而数的，有宿食停滞，当下之（使用泻下法）。如果伴有发热、呕吐恶心、心下痞硬，或者往来寒热，主方为大柴胡汤（Da Chai Hu Tang, Major Bupleurum Decoction）。（注释：阳明脉胜则洪缓为不负而顺，少阳脉胜则弦紧为负而逆）。
按语：三阳合病下利，只有少阳阳明合病最为严重，因为土（脾/胃）受木（肝/胆）克制。所以阳明脉胜为顺，阳明脉负为失，失者预后不良甚至死亡。（注释参考《伤寒来苏集》）。
三阴下利，都详细记载在本病章节下。如腹部胀满而疼痛，吐利交作，或者下利完谷不化（下利清谷），吐利伴四肢厥逆，或者下利身体沉重，小便不利等症状，都属于三阴本脏虚寒，应当使用理中汤（Li Zhong Tang, Regulate the Middle Decoction）、四逆汤（Si Ni Tang, Counterflow Decoction）、真武汤（Zhen Wu Tang, True Warrior Decoction）等方剂治疗。
三阴热邪导致的下利，太阴病有突然烦躁并下利，腹部胀满大痛，咽干口渴的症状。少阴病有自利清水，颜色纯青，心下疼痛、口干燥的症状，这些都是转属阳明病，适宜使用承气汤类方剂主治。少阴病又有四肢厥逆，泄利伴有肛门重坠感，小便不利，腹中疼痛的症状，也属于热邪，适宜使用四逆散（Si Ni San, Counterflow Powder）。厥阴病热利伴有肛门重坠感，想喝水，脉象弦而数，这是风木热邪乘袭脾脏，主方为白头翁汤（Bai Tou Weng Tang, Pulsatilla Decoction）。
邵评：阳经热邪传入太阴，热邪灼伤津液，转属阳明，形成胃实证候，都是热实的征象，所以可以使用下法。如果少阴热邪合并阳明症状，少阴经中热极，逼迫水液下流，而肾水燥竭，燥则肠中物质更加坚硬，所以利下清水，颜色纯青，这是肾弱而肝反侮之所致。心下痛为实证，口干燥为热证，使用大承气汤（Da Cheng Qi Tang, Major Order the Qi Decoction）急下燥屎以保存津液。至于四逆，是指四肢逆冷，阳气不能通达于四肢，所以逆冷。泄利伴有肛门重坠感，是阳邪下陷入阴，阳气在内而阴气反在外，阴阳脉气不相顺接。小便不利腹痛，是水气为患。使用四逆散和解表里之邪。只有热邪传入厥阴，成为协热下利，热利伴有肛门重坠感，乃湿热秽气郁遏于下焦广肠，所以魄门（肛门）重滞，虽然下利但难以排出。想喝水，是因为里有热邪，传经之邪被厥阴所接受。弦脉为肝脉，数脉代表里热。使用白头翁辛淡以祛除邪气，黄连、黄柏苦寒以清热，秦皮苦凉性涩，入厥阴经而止利。
又评：少阴四逆，是指四肢厥冷。这不是热厥，而是太阳初受寒邪，便入少阴的症状。少阴为阴枢，邪气居于此，可进可退，所以病症多有或然症（不一定出现的症状）。因此取四味药以散除四逆之邪，这是少阴气分的下剂。
凡是厥阴病，先发厥冷，后发热，如果不退热的，必然会出现便脓血。脉数有力，从阳治；脉沉无力，从阴治。
邵评：热不退，说明阳邪盛。阳盛则损伤阴络，所以知道必然便脓血。便血而脉数有力的，适宜滋阴清热，从阳治之。脉沉无力的，当温中和营，从阴治之。
Diarrhea resulting from the simultaneous involvement of the three Yang meridians presents with heat signs but no cold signs. Spontaneous diarrhea in the three Yin meridians belongs to cold syndromes. Yang pathogens are characterized by heat. In a combined disease of Taiyang (Taiyang Meridian) and Yangming (Yangming Meridian), spontaneous diarrhea indicates that wind pathogens have entered the stomach. The pulse is floating and long; the observed symptoms are those of Taiyang disease, but due to the presence of diarrhea, it is known to be a combined disease with Yangming. Ge Gen Tang (Pueraria Decoction) should be used to release the wind pathogen from the exterior, after which the diarrhea will cease naturally.
Shao's Commentary: Diarrhea differs in being either cold or heat. Diarrhea from combined disease of the three Yang meridians involves pathogens transforming into heat and entering the interior, presenting without cold symptoms. Diarrhea in the three Yin meridians arises from two causes: direct invasion (cold pathogens directly attacking the zang-fu organs) and transmission via meridians. Direct invasion leads to cold diarrhea, while transmission from Yang meridians results in heat diarrhea. When Taiyang pathogens merge into Yangming causing spontaneous diarrhea, it is termed combined disease of Taiyang and Yangming. In combined diseases, diarrhea occurs because internal qi descends due to heat. A floating pulse indicates Taiyang, and a long pulse indicates Yangming. The presence of Taiyang symptoms suggests that Taiyang pathogens have just entered the interior of Yangming. With the combination of two Yangs, Yang brightness is abundant, and pathogenic fire is vigorous, resulting in excess at the exterior and deficiency at the interior. Thus, external Taiyang symptoms appear, while internal diarrhea occurs. Ge Gen Tang, with its acrid-sweet dispersing properties, resolves the exterior by following Yang. This is the method of "lifting what has sunk" for pathogens combining in two Yangs. Furthermore, in combined disease of Taiyang and Yangming with diarrhea, Taiyang symptoms have sunk into Yangming; therefore, Ge Gen is added to exterior-releasing formulas to clear interior heat.
If Gui Zhi Tang Syndrome (Cinnamon Twig Decoction Syndrome) is mistakenly treated with purgatives, leading to unceasing diarrhea and a rapid pulse, the exterior pathogen remains unresolved. If accompanied by sweating and wheezing, Ge Gen Huang Qin Huang Lian Tang (Pueraria, Scutellaria and Coptis Decoction) should be used to release exterior pathogens and clear interior heat.
Shao's Commentary: Seven-tenths of cases involve Yang sinking internally, while three-tenths involve pathogens remaining at the exterior; hence, it is said that the exterior is not yet resolved. Pathogens constrain the exterior, and Yang disturbs the interior, causing wheezing and sweating. With both exterior and interior affected, the acrid-cool nature of Ge Gen releases the exterior, while the bitter-cold nature of Huang Qin (Scutellaria Root) and Huang Lian (Coptis Rhizome) clears the interior.
In combined disease of Taiyang and Shaoyang (Shaoyang Meridian) with spontaneous diarrhea, Huang Qin Tang (Scutellaria Decoction) is indicated. This is because heat pathogens have entered the interior of Shaoyang, where Gallbladder Fire is blazing and transferring heat to the Spleen, causing spontaneous diarrhea. The pulse is floating and wiry; external symptoms must include headache, chest fullness, bitter taste in the mouth, dry throat, dizziness, or alternating chills and fever. Since the heat pathogen is not at half-exterior but at half-interior, Chai Hu (Bupleurum Root) is not used; instead, Huang Qin is the principal herb. If vomiting occurs, Ban Xia (Pinellia Tuber) and Sheng Jiang (Fresh Ginger Rhizome) are added to treat phlegm-fluid retention.
Shao's Commentary: Shaoyang is located at half-exterior and half-interior, deeper than Yangming. Heat pathogens easily invade Taiyang and Shaoyang. In combined disease of two Yangs, Yang is excessive and Yin is deficient; Yang Qi sinks into Yin, causing spontaneous diarrhea. The treatment differs from Yangming. In combined disease of Taiyang and Yangming, pathogens have just entered the exterior of Yangming and are close to the outside; thus, Ge Gen drives pathogens out, making outward expulsion favorable. In combined disease of Taiyang and Shaoyang, pathogens have entered the interior of Shaoyang; thus, Huang Qin treats them, making inward expulsion easier. For heat overflowing internally, the bitterness of Huang Qin clears it. The intestines and stomach, heated and unconsolidated, are treated with the sourness of Bai Shao (White Peony Root) and the sweetness of Gan Cao (Licorice Root) to astringe and consolidate. Sour and bitter inducing drainage belong to Yin methods; this is also the method of "treating obstruction with draining agents" (using purgative/drainage methods for conditions presenting with discharge). If vomiting occurs, it is due to rebellious heat; thus, Ban Xia and Sheng Jiang disperse rebellious Qi, while Huang Qin clears the interior, an unchangeable principle. Huang Qin Tang is a modification of Xiao Chai Hu Tang (Minor Bupleurum Decoction). Since heat is not at half-exterior but has entered half-interior, Huang Qin clears the interior. Although there is no Stomach Excess (excess heat accumulation in the stomach/intestines), there is also no Stomach Deficiency, so Ren Shen (Ginseng Root) is not needed to tonify the middle.
Some argue that here "Shaoyang" refers to the San Jiao (Triple Burner), not the Gallbladder.
In combined disease of Shaoyang and Yangming with spontaneous diarrhea, if the pulse does not show "defeat" (i.e., Yangming pulse prevails), it is a favorable prognosis ("Shun"); if it shows "defeat" (i.e., Shaoyang pulse prevails), it is unfavorable ("Ni"). A slippery and rapid pulse indicates retained food stagnation and requires purgation. If accompanied by fever, nausea/vomiting, epigastric hardness, or alternating chills and fever, Da Chai Hu Tang (Major Bupleurum Decoction) is the primary formula. (Note: A Yangming pulse prevailing as surging and slow indicates no defeat and is favorable; a Shaoyang pulse prevailing as wiry and tight indicates defeat and is unfavorable.)
Analysis: Among combined diseases of the three Yang meridians with diarrhea, combined disease of Shaoyang and Yangming is the most severe because Earth (Spleen/Stomach) is controlled by Wood (Liver/Gallbladder). Therefore, a prevailing Yangming pulse is favorable, while a defeated Yangming pulse is adverse; defeat implies death. (See commentary in *Shang Han Lai Su Ji*).
Diarrhea in the three Yin meridians is detailed under their respective diseases. Symptoms such as abdominal fullness and pain, simultaneous vomiting and diarrhea, diarrhea with undigested food (clearing谷物), vomiting and diarrhea with four-inverse (limb coldness), or diarrhea with heavy body and ineffective urination all belong to deficiency-cold of the three Yin organ systems. They should be treated with Li Zhong Tang (Regulate the Middle Decoction), Si Ni Tang (Counterflow Decoction), Zhen Wu Tang (True Warrior Decoction), etc.
Shao's Commentary: This is the standard treatment for diarrhea caused by cold pathogens invading the three Yin meridians.
Diarrhea caused by heat pathogens in the three Yin meridians: Taiyin disease may present with sudden irritability and diarrhea, abdominal fullness and severe pain, dry throat, and thirst. Shaoyin disease may present with spontaneous diarrhea of clear water, pure green color, epigastric pain, and dry mouth. These are transformations involving Yangming and should be treated with Cheng Qi Tang (Order the Qi Decoction) category formulas. Shaoyin disease may also present with four-inverse, diarrhea with tenesmus (heavy sensation in anus), ineffective urination, and abdominal pain; these also belong to heat pathogens and should be treated with Si Ni San (Counterflow Powder). Jueyin (Jueyin Meridian) heat diarrhea with tenesmus and thirst for drinking water, with a wiry and rapid pulse, indicates wind-wood heat pathogens attacking the Spleen; Bai Tou Weng Tang (Pulsatilla Decoction) is indicated.
Shao's Commentary: Heat pathogens from Yang meridians transmitting to Taiyin burn fluids and transform into Yangming, forming Stomach Excess symptoms, all indicating heat-excess patterns, allowing for purgation. If Shaoyin heat merges with Yangming symptoms, extreme heat in the Shaoyin meridian forces water downward, drying Kidney Water; dryness makes intestinal contents harder, leading to diarrhea of clear water with pure green color, indicating weak Kidneys and Liver overacting. Epigastric pain indicates excess; dry mouth indicates heat. Da Cheng Qi Tang (Major Order the Qi Decoction) should be used urgently to purge dry feces and preserve fluids. As for "four-inverse," it refers to limb coldness due to Yang Qi failing to reach the limbs. Diarrhea with tenesmus indicates Yang pathogens sinking into Yin; Yang is internal while Yin is external, and Yin-Yang pulse Qi fail to connect smoothly. Ineffective urination and abdominal pain are caused by water-Qi pathology. Si Ni San harmonizes exterior and interior pathogens. Only when heat pathogens transmit to Jueyin, becoming協熱下利 (diarrhea with accompanying heat), does tenesmus occur due to damp-heat and turbid Qi stagnating in the lower Jiao and large intestine, causing heaviness in the魄門 (anus), making defecation difficult despite the urge. Thirst for water indicates internal heat; transmitted pathogens are accepted by Jueyin. A wiry pulse corresponds to the Liver; a rapid pulse indicates interior heat. Bai Tou Weng (Pulsatilla Root) is acrid and bland to dispel pathogens; Huang Lian (Coptis Rhizome) and Huang Bo (Phellodendron Bark) are bitter and cold to clear heat; Qin Pi (Ash Bark) is bitter, cool, and astringent, entering Jueyin to stop diarrhea.
Additional Commentary: Shaoyin four-inverse refers to limb coldness. This is not heat-jue (reversal due to heat); rather, it is a condition where Taiyang initially receives cold pathogens and immediately enters Shaoyin. Shaoyin is the Yin pivot; pathogens residing here can advance or retreat, leading to many possible symptoms. Thus, four herbs are taken to scatter the four-inverse pathogens; this is a descending agent for Shaoyin Qi-level disorders.
In all Jueyin diseases, if reversal cold occurs first followed by fever, and the fever does not subside, pus and blood in stool will inevitably occur. If the pulse is rapid and forceful, treat according to Yang; if the pulse is deep and powerless, treat according to Yin.
Shao's Commentary: Unsubdued fever indicates excessive Yang pathogens. Excessive Yang damages Yin collaterals, hence the certainty of pus and blood in stool. For bloody stool with a rapid, forceful pulse, nourish Yin and clear heat, treating according to Yang. For a deep, powerless pulse, warm the middle and harmonize Ying (Nutrient) Qi, treating according to Yin.