经义
诸呕吐酸，皆属于热。○少阳之胜，呕酸善饥。（《素问》）
哲言
酸者，肝木之味也。由火盛制金，不能平木，则肝木自甚，故为酸。如饮食热，则易于酸也。或言吐酸
为寒者，误也。又如酒之味苦性热，饮之则令人色赤气粗，喜怒如狂，烦渴呕吐，皆热证也。其吐必酸，为热
明矣。（刘河间）
吐酸之属于热者，与造酒相似，凉则甘，热则酸。（朱丹溪）
吐酸者，甚则酸水浸其心，令上下牙酸涩，不能相对，以辛热疗之必减。酸者收气也，西方金旺也。寒
水乃金之子，子能令母实，故用热剂泻其子，以泻肺之实。若以病机之法，作热攻之，误矣。杂病醋心，浊气
不降，欲为中满，寒药岂能治乎？（李东垣）
凡吞酸尽属肝木，曲直作酸也。河间主热，东垣主寒；东垣言其因，河间言其化。盖寒则阳气不舒，郁
而为热，热则酸矣。然亦有不因寒而酸者，木气郁甚，熏蒸湿土而成也。又有饮食太过，胃脘填塞，脾气不运
而酸者，是怫郁之极，湿热蒸变，如酒
缸太热则酸也。然总是木气所致，若非木气，即寒、即热、即饱、即怫郁，亦不酸，以酸为木气也。○又有一
种，饮食入胃，即成酸味，此必伤寒久疟，胃阴未复。当以淡味滋养真阴，而后可治也。（《己任编》）
吐酸，诸言为热者，岂不各有其说。在刘河间则曰∶如饮食热则易酸。在戴元礼则曰∶如谷肉在器，热易
为酸。又有相传者曰∶观之造酒，凉作则甘，热作则酸。岂非酸由热乎？诸说如此，宛然可信。但凡察病者，
当察其理；察理者，当察其真。即如饮食之酸由乎热，似近理矣。然食在釜中，使能化而不能酸者，此以火力
强，而速化无留也。若起置器中，必久而后酸，此停积而酸，非因热而酸也。尝见水浆冷积既久未有不酸者，
此岂热耶？因不行也。又云∶造酒者热作则酸，亦似近理。然必于二三日后，郁热不开，然后成酸，未有热作
及时，而遂致酸也。且人之胃气，原自大热，所以三餐入胃，俱能倾刻消化。若如造酒者，必待竟日而后成，
则日不再餐，胃气能无惫乎？若必如冷作之不酸，方云无火，则饮食之化，亦须旬日，此其胃中阳气不已竭乎？
是可见胃气本宜暖，稍凉不可也。酒瓮本宜疏，郁闷不可也。故酒瓮之化，亦安能如胃气之速；而胃气之健，
又安可同酒瓮之迟乎？人之饮食入胃，惟速化为贵。若胃中阳气不衰，健运如常，何酸之有？使火力不到，
则其化必迟；食化既迟，则停积不行，而为酸为腐，此酸即败之渐也。故凡病吞酸者，多见饮食不快，渐至中
满、痞隔、泄泻等证，岂非脾胃阳虚之病，而犹认为火，能无误乎？（张景岳）
或问∶吞酸，《素问》以为热，东垣又以为寒，何也？曰∶吐酸与吞酸不同。吐酸者，吐出酸水如醋，乃
平时津液，随上升之气，郁而成积，积久生热，故从木化，遂作酸味，非热而何？其有郁积之久，不能自涌而
出，伏于肺胃之间，咯不得上，咽不得下，肌表得风寒，则内热愈郁，酸味刺心，肌表温暖，腠理开
发，或得香热汤丸，津液得行，亦可暂解，非寒而何？《素问》言热，言其本也；东垣言寒，言其末也。但东
垣不言外得风寒，而作收气立说，欲泻肺金之实，未合《经》旨。余尝治吞酸，用连、萸各制，随时令为佐使，
以苍术、茯苓为辅，汤浸蒸饼为丸吞之，教以淡食自养，则病易安。（《局方发挥》）
吐酸者，吐出酸水如醋，夹痰居多，痰郁水亦郁，自成酸矣。一遇上升之气，则痰与水并出。盖未有酸水
而无痰者也。治用二陈汤，加栀子、姜炒黄连、苍白术，少加吴萸为引经。凡治酸必少用吴萸者，盖因其性而
折之也。（虞天民）
肝为尽阴，胆无别窍，故胃中水谷，一有所积，辄遏肝胆之火，曲直而不得伸，癖以是成，热由此郁。木
中有此郁热之火，金畏而不敢平，胜我者不能平，我胜者不得去，湿热无从宣泄，此吐酸之所由来也。法宜寒
因热用，于木中泻去火邪，使金无所畏而木可平；用热性引入肝胆，使辛有所宣而郁可达。金行从左，何木令
之不条耶？（程郊倩）
凡积滞中焦，久郁成热，因而作酸者，此酸之属于热也。若客寒犯胃，顷刻成酸，本无郁热，因寒所化者，
此酸之属于寒也。○吞酸虽小疾，然可暂不可久，久而不愈，为噎隔反胃之渐。若脉两关俱弦者，尤宜慎防，
以木来凌土故耳。（《证治汇补》）
病转入胃，煎熬津液，变成酸汁，胃口有如醋瓮。胃中之热，有如曲 ，谷饮一入，顷刻酿成酢味矣。有
时新谷方咽，旧谷即为迸出，若互换者；缘新谷芳甘未变，胃爱而受之，其酸腐之余，自不能留也。夫人身天
真之气，全在胃口，今暗从火化，津液升腾屑越，已非细故。况土曰稼穑，作甘者也；木曰曲直，作酸者也。
甘反作酸，木来侮土，故驱其酸，而反其甘，惟有用刚药一法。刚药者，气味俱雄之药，能变胃而不受胃变者
也。但可用刚中之柔，不可用柔中之刚，如六味加桂、附，柔中之刚也。于六味作酸药中，入二味止酸药，当
乎不当乎？刚中之柔，如连
理汤丸是也。刚非过刚，更有柔以济其刚，可收去酸之绩矣。（喻嘉言）
吞酸，多属脾虚木旺。证见面色萎黄，胸膈不利。世医每投清气化痰之药，多致便泻食少而危。此证当用
六君子汤，加炮姜、木香、吴茱萸。若脾肾俱虚者，宜用六君子汤，加肉蔻、补骨脂。中气虚弱者，宜用理中
汤，加吴茱萸。其有郁火，服连理汤不应者，宜用补中益气汤，加木香、炮姜，送左金丸。中气虚寒者，宜用
附子理中汤。（薛立斋）
脉候
吐酸之脉∶弦滑为痰滞于内，浮紧为寒束于外；沉迟为中寒，洪数为火盛。（《医鉴》）
选案
方含光，患吐酸。医以平肝降气治之，久而饮食亦吐，二便渐稀。又以噎隔将成，恣用香燥，关窍愈塞。
予谓∶始患吐酸者，肝木郁也；吐及饮食者，肝郁下克脾土也；二便渐稀者，土虚不能传化也。初缘肾水枯竭，
肝木无以滋生，酿成郁闷。是时但与滋肾舒肝之剂，亦易为力，奈何用气分重药，益其煎熬耶？以回天饮煎进
代茶，一日便通，两日吐止，三日全安。（程华仲）
吴维师内，患胃脘痛，体中忽热忽止，觉有气逆左胁上，呕吐酸水，饮食俱出。或疑停滞，或疑感邪，或
疑寒凝，或疑痰积。诊脉弦数，重按则濡，乃火郁肝血燥耳。与以归、芍、地黄、柴胡、枣仁、山药、萸肉、
丹皮、山栀、茯苓、泽泻顿安。胃口犹觉劣劣，用加味归脾汤，及滋肝补肾丸而愈。○沈孟嘉妻，患吞酸膈痛，
肌肉枯削，几于绝粒，诊脉细数，此肝木乘脾也。先投六君子汤加炮姜，觉酸减半。继用补中益气汤，加半夏、
炮姜，酸去膈痛亦除。次用归脾汤，吞八味丸而愈。（《己任编》）
一人心前作辣，医用滋阴之剂反甚。又云是火，服黄连更增腹胀，食不过膈，吐出则辣稍解，小便不利，
面青唇黄，语轻气
乏，脉息沉细，舌苔色黑，此阴寒之极也。其病虽在上焦，其源由于肾阳下衰，不能上蒸脾土，而熟腐五谷，
以致食入不化，停塞胃脘，故尔作酸，终不传化下行，故复吐出。反用黄连寒其脾土，安望其能健运乎？必须
温养脾土，使春阳发舒，庶可生物，而无寒凝之患。方用桂、附、炮姜、白术、茯苓、炙甘草、木香、陈皮、
人参，服药四剂，食能过膈，辣亦减半。去木香加黄 、熟地，服之而愈。（吴天士）
[Scriptural Meaning]
Various types of vomiting and sour regurgitation all belong to Heat syndromes. ○ When Shaoyang (Lesser Yang) pathogenic factors prevail, symptoms include vomiting sour fluid and easy hunger occur. (From *Suwen*)
[Philosophical Discourse]
Sourness is the flavor corresponding to Liver Wood. It arises because excessive Fire controls Lung Metal, preventing Metal from properly restraining Wood; thus, Liver Wood becomes hyperactive, resulting in sourness. For instance, when food is heated, it tends to become sour. Some claim that vomiting sour fluid belongs to Cold, which is erroneous. Take wine as an example: its flavor is bitter and its nature is hot. Drinking it causes flushed complexion, coarse breathing, manic-like anger or joy, irritability, thirst, and vomiting—all are signs of Heat syndromes. The vomit must be sour, clearly indicating that sour regurgitation is caused by Heat. (Liu Hejian)
The case of sour regurgitation belonging to Heat is similar to brewing wine: when cool, it is sweet; when hot, it becomes sour. (Zhu Danxi)
In cases of sour regurgitation, severe instances involve sour fluid soaking the heart, causing astringency and soreness in the upper and lower teeth, making them unable to close against each other. Treatment with acrid-hot herbs will inevitably reduce these symptoms. Sourness corresponds to the Qi of gathering/restraining, associated with Western Metal. Cold Water is the son of Metal; the son can strengthen the mother. Therefore, using hot decoctions to drain the "son" (Kidney Water) indirectly drains the excess of Lung Metal. If one treats this according to disease mechanism principles as a Heat syndrome and attacks it with cold methods, it would be a mistake. In miscellaneous diseases, the sensation of vinegar-heart occurs due to turbid Qi failing to descend, leading to a desire for middle-fullness; how can cold herbs treat this? (Li Dongyuan)
All cases of swallowing sour fluid belong to Liver Wood, as Wood's nature is crooked/straight, producing sourness. Liu Hejian emphasized Heat, while Li Dongyuan emphasized Cold; Li discussed the etiology, while Liu discussed the transformation. Generally, Cold causes Yang Qi to fail to circulate freely, stagnating into Heat, which then produces sourness. However, there are cases not caused by Cold but by severe stagnation of Wood Qi steaming Spleen Earth. There are also cases where excessive eating blocks the stomach cavity, Spleen Qi fails to transport, leading to sourness due to extreme frustration/stagnation and steaming of Damp-Heat, similar to a wine vat becoming sour when too hot. Ultimately, this is caused by Wood Qi. Without Wood Qi, even if there is Cold, Heat, fullness, or stagnation, sourness will not occur, because sourness is the manifestation of Wood Qi. ○ Another type involves food entering the stomach and immediately turning sour; this must be due to Stomach Yin not yet restored after prolonged Taiyang Cold Damage or chronic malaria. One should nourish True Yin with bland-flavored herbs before treating further. (*Jiren Bian*)
Regarding sour regurgitation, various physicians argue it is Heat, each having their rationale. Liu Hejian stated that food heated easily becomes sour. Dai Yanli stated that grains and meats in containers easily become sour when heated. Another traditional view observes winemaking: cool production yields sweetness, hot production yields sourness. Does this not imply sourness comes from Heat? These arguments seem plausible. However, physicians must examine the principle; examining the principle requires seeking the truth. Although food turning sour due to heat seems logical, food in a pot that digests quickly without turning sour does so because strong fire rapidly transforms it without retention. If removed to a container, it takes time to turn sour due to accumulation, not directly because of heat. I have seen cold water accumulating for long periods always turning sour; is this Heat? No, it is due to stagnation. Regarding winemaking, heat leads to sourness only after two or three days of stagnant heat opening up; it does not happen immediately upon heating. Furthermore, human Stomach Qi is originally very hot, digesting meals instantly. If digestion took a whole day like winemaking, one could not eat three times a day without exhausting Stomach Qi. If we claimed no Fire existed just because cold things don't turn sour, digestion would take ten days, depleting Stomach Yang. Thus, Stomach Qi should be warm, not cool. Wine vats need ventilation, not stifling. Winemaking cannot match the speed of Stomach Qi, nor should Stomach Qi be compared to the slowness of a vat. Human food entering the stomach values rapid transformation. If Stomach Yang is robust, where is the sourness? If Fire power is insufficient, transformation slows; slow transformation leads to accumulation and putrefaction/sourness, which is the beginning of decay. Therefore, patients with swallowing sour fluid often show poor appetite, progressing to middle-fullness, chest oppression, and diarrhea. Is this not a Spleen-Stomach Yang Deficiency disease mistakenly treated as Fire? Can this not lead to error? (Zhang Jingyue)
A question arises: *Suwen* considers swallowing sour fluid as Heat, while Li Dongyuan considers it Cold. Why? Answer: Vomiting sour fluid differs from swallowing sour fluid. Vomiting sour fluid involves expelling acid water like vinegar; this is normal body fluid rising with ascending Qi, stagnating into accumulation, generating Heat over time, transforming via Wood, thus becoming sour—is this not Heat? Those with long-standing stagnation that cannot erupt spontaneously lie between Lung and Stomach; they cannot be coughed up or swallowed down. When skin/surface encounters Wind-Cold, internal Heat becomes more constrained, sourness pierces the heart. When skin/warmth opens pores, or aromatic-hot pills/decoctions allow fluid circulation, temporary relief occurs—is this not Cold? *Suwen* speaks of Heat regarding the root; Li Dongyuan speaks of Cold regarding the branch. However, Li did not mention external Wind-Cold but based his theory on the Qi of gathering/restraining to drain Lung Metal excess, which does not fully align with the Classics. I once treated swallowing sour fluid using processed Coptis Rhizome (*Huanglian*) and Evodia Fruit (*Wuzhuyu*) as assistants according to seasons, supported by Atractylodes Rhizome (*Cangzhu*) and Poria (*Fuling*), formed into pills with steamed bread soaked in soup, advising bland diet for self-nourishment, leading to recovery. (*Jufang Fahui*)
Vomiting sour fluid involves expelling acid water like vinegar, mostly mixed with Phlegm. When Phlegm stagnates, Water also stagnates, naturally forming sourness. Upon encountering ascending Qi, Phlegm and Water are expelled together. There is rarely sour water without Phlegm. Treatment uses Erchen Decoction (*Two-Aged Powder*) plus Gardenia Fruit (*Zhizi*), Ginger-fried Coptis Rhizome (*Huanglian*), White and Black Atractylodes Rhizomes (*Baizhu*, *Cangzhu*), with a small amount of Evodia Fruit (*Wuzhuyu*) as a guiding herb. Evodia is used sparingly in treating sourness to counteract its nature. (Yu Tianmin)
Liver is the ultimate Yin organ; Gallbladder has no separate orifice. Thus, any accumulation of water and grain in the Stomach obstructs Liver-Gallbladder Fire, preventing its free flow, leading to masses and郁 Heat. This郁 Heat within Wood makes Metal fearful and unable to restrain it; the element that usually restrains Wood cannot do so, and Wood cannot eliminate Metal. Damp-Heat has no outlet for discharge, giving rise to sour regurgitation. The method should employ "treating Heat with Hot [herbs]" (Han Yin Re Yong), draining Fire evil from Wood so Metal is no longer afraid and can restrain Wood; using hot-natured herbs to enter Liver/Gallbladder meridians so Acrid flavors can disperse and resolve stagnation. Since Metal moves from the left, why would Wood fail to be smooth and unobstructed? (Cheng Jiaoqian)
Cases where stagnation in the Middle Jiao stagnates for a long time transforming into Heat, thereby producing sourness, belong to Heat-type swallowing sour fluid. Cases where exogenous Cold invades the Stomach, instantly producing sourness without prior郁 Heat, transformed by Cold, belong to Cold-type swallowing sour fluid. ○ Swallowing sour fluid, though a minor ailment, allows only temporary relief, not cure; if untreated long-term, it becomes a precursor to dysphagia, chest obstruction, and regurgitation. If the pulse is wiry at both Guan positions, caution is especially needed, as this indicates Wood attacking Earth. (*Zhengzhi Huibu*)
Pathogenic factors entering the Stomach ferment body fluids, turning them into acid juice, making the stomach gate like a vinegar jar. The Heat in the Stomach acts like yeast; once grain or drink enters, it instantly brews into an acidic taste. Sometimes new food swallowed causes old food to burst out, as if exchanging places; because new food is still fragrant and sweet, the Stomach accepts it, while the sour/putrid remnants cannot stay. The innate Qi of the body resides in the stomach gate; now it secretly transforms via Fire, with body fluids rising and overflowing, which is significant. Earth governs sowing and reaping, producing Sweetness; Wood governs bending and straightening, producing Sourness. Sweetness turning to Sourness indicates Wood insulting Earth. To drive out the sourness and restore sweetness, one must use "Gang [Strong/Rigid] Herbs." Gang herbs have potent aromas and flavors, capable of changing the Stomach's state without being changed by it. One should use "Rigidity within Softness," not "Softness within Rigidity." For example, Liuwei Dihuang Wan plus Cinnamon Twig (*Guizhi*) and Prepared Aconite Root (*Fuzi*) represents Softness within Rigidity. Adding two anti-sour herbs to Liuwei Dihuang Wan—is this appropriate? Lianli Tang Wan represents Rigidity within Softness. Rigidity is not overly rigid; Softness assists Rigidity, achieving the goal of removing sourness. (Yu Jiayan)
Swallowing sour fluid mostly belongs to Spleen Deficiency and Liver Hyperactivity. Symptoms include sallow complexion and chest/diaphragm discomfort. Worldly physicians often prescribe Clear-Qi and Transform-Phlegm herbs, often leading to diarrhea, poor appetite, and critical conditions. This syndrome should be treated with Liujunzi Decoction (*Six Gentlemen Decoction*) plus Roasted Ginger (*Paojiang*), Aucklandia Root (*Muxiang*), and Evodia Fruit (*Wuzhuyu*). If Spleen and Kidney are both deficient, use Liujunzi Decoction plus Nutmeg (*Roukou*) and Psoralea Fruit (*Buguzhi*). If Middle Qi is weak, use Lizhong Decoction (*Center-Regulating Decoction*) plus Evodia Fruit. If there is郁 Fire and Lianli Tang is ineffective, use Buzhong Yiqi Decoction (*Tonify the Middle and Augment the Qi Decoction*) plus Aucklandia Root and Roasted Ginger, taken with Zuojin Wan (*Left Metal Pill*). If Middle Qi is deficient and Cold, use Fuzi Lizhong Decoction. (Xue Lizhai)
[Pulse Diagnosis]
Pulses for sour regurgitation: Wiry and Slippery indicate Phlegm stagnation internally; Floating and Tight indicate Cold binding externally; Deep and Slow indicate Interior Cold; Surging and Rapid indicate Excessive Fire. (*Yijian*)
[Selected Cases]
Fang Hanguang suffered from sour regurgitation. Physicians treated him with Liver-calming and Qi-descending methods. Over time, he vomited even food, and bowel/bladder movements became loose. Later, fearing impending dysphagia, they recklessly used aromatic-dry herbs, further blocking the orifices. I reasoned: Initially, sour regurgitation was due to Liver Wood stagnation; vomiting food indicated Liver stagnation attacking Spleen Earth; loose stools indicated Earth deficiency failing to transform/transmit. Originally, Kidney Water was depleted, failing to nourish Liver Wood,酿成 (brewing) depression. At that time, providing Kidney-nourishing and Liver-soothing agents would have been effective. Instead, heavy Qi-moving drugs were used, exacerbating the consumption. I prescribed Huitian Yin (*Return to Heaven Decoction*) as tea substitute. Bowel movement normalized in one day, vomiting stopped in two, and full recovery occurred in three. (Cheng Huazhong)
Wu Weishi’s wife suffered from epigastric pain, alternating fever and chills, sensation of Qi reversing up the left hypochondrium, vomiting sour fluid and food. Differential diagnoses included food stagnation, pathogenic invasion, Cold coagulation, or Phlegm accumulation. Pulse was Wiry-Rapid, soft upon deep pressure, indicating Fire stagnation and Liver Blood dryness. Prescribed Angelica Sinensis Root (*Danggui*), White Peony Root (*Baishao*), Rehmannia Root (*Dihuang*), Bupleurum Root (*Chaihu), Ziziphus Seed (*Zaoren*), Chinese Yam (*Shanyao*), Cornus Fruit (*Shanzhuyu*), Moutan Bark (*Danpi*), Gardenia Fruit (*Shanzhi*), Poria (*Fuling*), and Alisma Rhizome (*Zexie*). She felt immediate relief. Appetite remained poor, so Jiawei Guipi Tang (*Modified Restore the Spleen Decoction*) and Liver-Nourishing/Kidney-Tonifying Pills were used for complete recovery. ○ Shen Mengjia’s wife suffered from swallowing sour fluid and chest pain, emaciation, nearly fasting completely. Pulse was Fine-Rapid, indicating Liver Wood attacking Spleen. First administered Liujunzi Decoction plus Roasted Ginger; sourness halved. Then Buzhong Yiqi Decoction plus Pinellia Tuber (*Banxia*) and Roasted Ginger; sourness and chest pain resolved. Finally, Guipi Tang and Bawei Wan (*Eight Flavor Pill*) cured her. (*Jiren Bian*)
A patient felt spiciness in the precordial region. Physicians used Yin-nourishing herbs, worsening symptoms. Others diagnosed Fire, prescribing Coptis Rhizome (*Huanglian*), increasing abdominal distension. Food could not pass the diaphragm; vomiting provided slight relief. Urination was difficult, complexion green, lips yellow, voice quiet, Qi deficient, pulse Deep-Fine, tongue coating black. This was Extreme Yin Cold. Though the pathology appeared in the Upper Jiao, the source was Kidney Yang decline below, failing to steam Spleen Earth to cook grains, causing food stagnation in the Stomach, turning sour, and regurgitating. Using cold Coptis to chill Spleen Earth prevents transportation. One must warm and nourish Spleen Earth to allow Spring Yang to expand, avoiding Cold stagnation. Formula: Cinnamon Twig (*Guizhi*), Prepared Aconite Root (*Fuzi*), Roasted Ginger (*Paojiang*), Atractylodes Macrocephala Rhizome (*Baizhu*), Poria (*Fuling*), Honey-fried Licorice Root (*Gancao*), Aucklandia Root (*Muxiang*), Tangerine Peel (*Chenpi*), Ginseng Root (*Renshen*). After four doses, food passed the diaphragm, spiciness halved. Remove Muxiang, add Astragalus Root (*Huangqi*) and Prepared Rehmannia Root (*Shudi*), cured. (Wu Tianshi)