《论》曰∶三阴皆受病，已入于府者，可下而已。此详义见前六经证。
曰∶脉浮而大，心下反硬，有热属脏者，攻之，不令发汗。按∶此以心下硬而热在脏，即脉虽
浮大者，病亦属里，故不宜发汗，而当攻内也。
曰∶伤寒不大便六七日，头痛有热者，与承气汤。按∶此以阳明内热而为头痛也，故可攻之。
曰∶阳明病，外已解而潮热者，可攻里也，手足 然而汗出者，此大便已硬也，大承气汤主之
。若汗虽多，而微发热恶寒者，表未解也，其热不潮，未可与承气。
曰∶阳明病，胃中有燥屎者，可攻之。病患不大便五六日，绕脐痛，烦躁，发作有时者，此有
燥屎也。
曰∶汗出谵语者，以有燥屎在胃中，此为风也，须下之，宜大承气汤。
曰∶阳明病，发热汗多者，热在里也，急下之，宜大承气汤。
曰∶阳明病，发汗不解，腹满痛者，邪在里也，急下之，宜大承气汤。
曰∶病腹中满痛者，此为实也，当下之。
曰∶腹满不减，减不足言，当下之，宜大承气汤。
曰∶伤寒六七日，结胸热实，脉沉而紧，心下痛，按之石硬者，或心下至少腹硬满而痛不可近
者，大陷胸汤主之。
曰∶阳明少阳合病，脉滑而数者，有宿食也，当下之，宜大承气汤。按∶此一条必须兼脉证而
察之，盖伤寒之脉滑数者多，若无胀痛等证，未必即为宿食，故不可单据滑数之脉，便认作可攻之
证。
曰∶若表已解而内不消，非大满，犹生寒热，则病不除也。按此一条言若非大满，而犹生寒热
者，是表
病犹不除也，尚不可下。
曰∶若表已解而内不消，大满大实坚，有燥屎，自可徐下之，虽四五日不能为祸也。若不宜下
而便攻之，内虚热入，协热遂利，烦躁诸变，不可胜数，轻者困笃，重者必死矣。按∶此一条言
外无表证，内有坚满，然后可下，正以见下不宜轻。轻下者，为祸不小也。
曰∶太阳病，热结耪胱，其人如狂，血自下，下者愈。若表未解者，不可攻，当先解表。表已
解，但少腹急结者，乃可攻之，宜桃仁承气汤。
一、凡伤寒当下者，不宜用丸药，以丸药不能涤荡热邪，而但能损正气也。又凡治伤寒热邪传里
者，服下药后，仍用盐炒麸皮一升许，将绢包于病患腹上，款款熨之，使药气得热则行，大便必易
通也。
一、脉有忌下者，如《伤寒论》曰∶伤寒脉微而恶寒者，此阴阳俱虚，不可更发汗，更吐，更下
也。寸口脉浮大，而医反下之，此为大逆。关脉弱，胃气虚有热，不可大攻之，热去则寒起。尺脉
涩弱无力者，不可下。大便硬者当下之，设脉迟缓者不可下，里气不实也。脉虚细者不可下。脉浮
者不可下。脉濡而弱，弱反在关，濡反在巅，弦反在上，微反在下。弦为阳运，微为阴寒，上实下
虚，意欲得温。微弦为虚，虚者不宜下也。脉浮而大，浮为气实，大为血虚，血虚为无阴，孤阳独
下阴部者，医以为热，而复用毒药攻其胃，此为重虚，客阳去有期，必下如污泥而死。脉濡而紧，
濡则阳气微，紧则荣中寒，阳微卫中风，发热而恶寒，荣紧胃气冷，微呕心内烦。医谓有大热，
解肌而发汗，亡阳虚烦躁，心下苦痞坚，表里俱虚竭，卒起而头眩，客热在皮肤，胀怏不得眠。不
知胃气冷，紧寒在关元，当温反下之，安可复追还。脉久数者，非外邪也，不可下之。脉细数者，
非实邪也；不可下。结胸证，其脉浮大者，邪未入府也，不可下，下之则死。大抵伤寒最宜慎下，
若
脉息无力，及表证未罢者，不可乱投汤剂，下之为逆。
一、证有忌下者，如太阳病外证未解，不可下，下之为逆。太阳与阳明合病，喘而胸满者，邪
在表也，不可下。阳明病，若微发热恶寒者，表未解也，不可下。阳明病，潮热，大便初硬后溏者
，不可攻。阳明病，腹微满，初头硬，后必溏者，非实热也，不可攻之。阳明病，其热不潮者，未
可与承气汤。阳明病，虽有潮热，而大便不硬者，不可与承气汤。不转失气者，其内不坚，慎不可
攻也。阳明病，心下硬满者，不可攻，攻之利遂不止者死。硬在心下者，其邪在胸膈，犹未入腑也
，故不可攻。脏结无阳证，不往来寒热，其人反静，舌上苔滑者，不可攻也。病欲吐者，不可下。
呕多，虽有阳明证，不可攻之。此呕多者，病在上焦，病在上而攻其下，取败之道也。阳明病，若
汗多，微发热恶寒者，外未解也，其热不潮，未可与承气汤。湿家下之，额上汗出，微喘，小便不
利者死，下痢不止亦死。阳明病，不能食，攻其热必哕，所以然者，胃中虚冷故也。以其人本虚，
故攻其热必哕。阴强无阳者，虽其大便坚硬，亦不可下，下之则清谷腹满。阴阳俱虚，恶水者。若
下之，则里冷，不嗜食，大便完谷出。阳微者不可下，下之则心下痞硬。恶寒者，不可下。小便清
利者，火不盛也，不可下。诸四逆厥者，不可下。咽中闭塞者不可下。发汗多，亡阳谵语者不可下
。诸虚者不可下，下之则阳虚而生寒。仲景曰∶极寒反汗出，身必冷如冰，其有眼睛不慧，语言不
休，口虽欲言，舌不得前者皆死。阴虚水亏，虚烦虚躁者不可下，重亡其阴，万无生理矣。
《黄帝内经》说：三阴经都受了病邪，如果病邪已经传入腑，可以通过泻下法来治疗。这一详细含义在前面六经证候中已有说明。
又说：脉象浮而大，心窝部反而硬满，有热邪归属于脏的，应当用攻下法，不要发汗。按语：这是因为心下硬满且热在脏，所以即使脉象浮大，病也属于里证，因此不适宜发汗，而应当攻逐里实。
又说：伤寒后六七天不大便，伴有头痛和发热的，给予承气汤。按语：这是因为阳明内热导致头痛，所以可以攻下。
又说：阳明病，表证已解而出现潮热的，可以攻里；手足濈然汗出的，这是大便已经干硬，以大承气汤为主治方。如果汗出虽然多，但仍有轻微发热恶寒的，说明表证未解，其热不是潮热，不可给予承气汤。
又说：阳明病，胃中有燥屎的，可以攻下。病人五六天不大便，绕脐疼痛，烦躁，定时发作的，这是有燥屎。
又说：出汗并说胡话的，是因为胃中有燥屎，这是风邪所致，必须攻下，宜用大承气汤。
又说：阳明病，发热汗多的，是热在里，需紧急攻下，宜用大承气汤。
又说：阳明病，发汗后病不解，腹部胀满疼痛的，是邪气在里，需紧急攻下，宜用大承气汤。
又说：腹部胀满不减，即使减轻也不足挂齿的，应当用泻下法，宜用大承气汤。
又说：伤寒六七天，出现结胸热实证，脉象沉而紧，心下疼痛，按压像石头一样硬的，或者从心下至少腹硬满且疼痛拒按的，以大陷胸汤为主治方。
又说：阳明病与少阳合病，脉象滑而数的，是有宿食，应当用泻下法，宜用大承气汤。按语：这一条必须结合脉象和证候综合考察，因为伤寒脉象滑数的情况很多，如果没有胀痛等证候，未必就是宿食，所以不能仅凭滑数之脉就认定为可攻之证。
又说：如果表证已解而体内积滞不消，如果不是大满大实，仍然产生寒热，那么病就不会痊愈。按语：这一条说的是如果不是大满大实，而仍然有寒热的，说明表病仍未解除，尚不可用泻下法。
又说：如果表证已解而体内积滞不消，出现大满、大实、坚结，有燥屎，可以慢慢攻下，即使过了四五天也不会造成祸害。如果不适合攻下却强行攻下，会导致正气虚弱、热邪内陷，导致协热下利，烦躁等各种变证，数不胜数，轻者病情加重，重者必死。按语：这一条说的是外无表证，内有坚满，然后才可以攻下，正是为了说明泻下不宜轻易使用。轻率攻下，灾祸不小。
又说：太阳病，热结膀胱，病人神志如狂，瘀血自行下行，下后病愈。如果表证未解，不可攻下，应当先解表。表证已解，只有少腹急迫结聚的，才可以攻下，宜用桃仁承气汤。
一、凡是伤寒应当用泻下法的，不宜使用丸药，因为丸药不能涤荡热邪，反而会损伤正气。另外，凡是治疗伤寒热邪传里的，服用下药后，仍应用盐炒麸皮约一升，用绢布包好放在患者腹部上，缓缓熨烫，使药气受热则运行，大便必然容易通畅。
一、脉象有忌用泻下的，如《伤寒论》说：伤寒脉微而恶寒的，这是阴阳俱虚，不可再发汗、催吐或泻下。寸口脉浮大，医生反而用泻下法，这是大逆。关脉弱，胃气虚而有热，不可猛烈攻下，热去则寒起。尺脉涩弱无力的，不可泻下。大便硬的当下之，但如果脉迟缓的不可下，因为里气不实。脉虚细的不可下。脉浮的不可下。脉濡而弱，弱脉反见于关部，濡脉反见于巅顶（寸部），弦脉反见于上部，微脉反见于下部。弦为阳气运行，微为阴寒，上实下虚，意念想要温补。微弦为虚，虚者不宜下。脉浮而大，浮为气实，大为血虚，血虚即为无阴，孤阳独陷于阴部的，医生误认为是热，又用毒药攻伐胃气，这是双重虚损，客阳离去有期，必然下如污泥而死。脉濡而紧，濡则阳气微弱，紧则营中有寒，阳微卫中风，发热而恶寒，营紧胃气冷，微呕心中烦闷。医生认为有大热，用解肌发汗法，导致亡阳虚烦躁，心下苦于痞塞坚硬，表里俱虚竭，突然起身则头晕，客热在皮肤，胀闷不得眠。不知胃气冷，紧寒在关元，本当温补反而泻下，怎么可以再追回？脉久数的，不是外邪，不可下。脉细数的，不是实邪，不可下。结胸证，脉浮大的，邪气未入腑，不可下，下之则死。大抵伤寒最宜谨慎使用泻下法，如果脉息无力，及表证未罢的，不可乱投汤剂，用泻下法是逆治。
一、证候有忌用泻下的，如太阳病外证未解，不可下，下之为逆。太阳与阳明合病，喘而胸满的，邪在表，不可下。阳明病，如果有轻微发热恶寒的，表未解，不可下。阳明病，潮热，大便初硬后溏的，不可攻。阳明病，腹部轻微胀满，开头硬，后来必定溏的，不是实热，不可攻。阳明病，其热不潮的，不可给予承气汤。阳明病，虽然有潮热，但大便不硬的，不可给予承气汤。不转矢气的，其内不坚，慎不可攻。阳明病，心下硬满的，不可攻，攻之腹泻不止者死。硬在心下的，邪在胸膈，尚未入腑，故不可攻。脏结无阳证，不往来寒热，病人反而安静，舌苔滑的，不可攻。想呕吐的，不可下。呕吐多，虽有阳明证，不可攻。此呕吐多者，病在上焦，病在上而攻其下，是取败之道。阳明病，如果汗多，微发热恶寒的，外未解，其热不潮，不可给予承气汤。湿家误下，额上汗出，微喘，小便不利的死，下痢不止也死。阳明病，不能进食，攻其热必呃逆，之所以这样，是因为胃中虚冷。因为病人本虚，所以攻其热必呃逆。阴强无阳的，虽然大便坚硬，也不可下，下之则完谷不化腹满。阴阳俱虚，恶水的。如果下之，则里冷，不嗜食，大便完谷出。阳微者不可下，下之则心下痞硬。恶寒者，不可下。小便清利的，火不盛，不可下。各种四肢厥逆者，不可下。咽中闭塞者不可下。发汗多，亡阳谵语的不可下。各种虚证不可下，下之则阳虚而生寒。仲景说：极寒反而汗出，身体必冷如冰，眼睛不灵活，语言不休，口虽欲言，舌头不能伸前的皆死。阴虚水亏，虚烦虚躁的不可下，重伤其阴，万无生理了。
The *Huangdi Neijing* states: When the three Yin meridians are all affected by pathogenic factors, and the pathogen has entered the Fu organs, purgation (Xia Fa) may be used. The detailed meaning of this is explained in the preceding section on Six Meridian syndromes.
It also states: If the pulse is floating and large, the epigastrium is rigid, and heat belongs to the Zang organs, attack with purgation; do not induce sweating. Commentary: This refers to rigidity in the epigastrium with heat residing in the Zang organs. Even if the pulse is floating and large, the disease belongs to the interior; therefore, inducing sweating is inappropriate, and internal purgation should be employed.
It further states: In cold damage (Shanghan), if there is no bowel movement for six or seven days accompanied by headache and fever, administer Chengqi Tang. Commentary: This is due to Yangming internal heat causing headache, so purgation is applicable.
It states: In Yangming disease, if the exterior syndrome has resolved and tidal fever (Chao Re) occurs, the interior can be attacked. If the hands and feet sweat continuously (Ji Ran Han Chu), this indicates that the stool has become hard; Da Chengqi Tang is the primary formula. However, if although sweating is profuse, there is still slight fever and aversion to cold, the exterior has not yet resolved, and the fever is not tidal; Chengqi Tang should not be given.
It states: In Yangming disease, if there is dry fecal matter (Zao Shi) in the stomach, it can be attacked. If a patient has not had a bowel movement for five or six days, experiences periumbilical pain, irritability, and symptoms that occur at specific times, this indicates the presence of dry fecal matter.
It states: If there is sweating and delirium (Chan Yu), it is because there is dry fecal matter in the stomach; this is caused by wind pathogen. Purging is required, and Da Chengqi Tang is appropriate.
It states: In Yangming disease, if there is fever and profuse sweating, the heat is in the interior. Urgent purgation is needed, and Da Chengqi Tang is appropriate.
It states: In Yangming disease, if sweating fails to resolve the condition and abdominal fullness and pain occur, the pathogen is in the interior. Urgent purgation is needed, and Da Chengqi Tang is appropriate.
It states: If there is abdominal fullness and pain, this is an excess syndrome, and purgation should be used.
It states: If abdominal fullness does not decrease, or decreases insignificantly, purgation should be used, and Da Chengqi Tang is appropriate.
It states: In cold damage, after six or seven days, if there is a Jie Xiong (Chest Binding) heat-excess syndrome, with a deep and tight pulse, pain in the epigastrium, and hardness upon palpation like stone, or hardness and fullness from the epigastrium down to the lower abdomen with pain that cannot be touched, Da Xianxiong Tang is the primary formula.
It states: In combined Yangming and Shaoyang disease, if the pulse is slippery and rapid, there is retained food (Su Shi). Purgation should be used, and Da Chengqi Tang is appropriate. Commentary: This clause must be examined by combining pulse and syndrome findings. Many cases of cold damage present with slippery and rapid pulses. Without symptoms such as distension and pain, it is not necessarily retained food. Therefore, one cannot rely solely on a slippery and rapid pulse to identify a purgable syndrome.
It states: If the exterior has resolved but internal stagnation remains, and if it is not a case of great fullness and solid accumulation, but chills and fever persist, the disease will not be cured. Commentary: This clause explains that if it is not a case of great fullness and solid accumulation, but chills and fever persist, the exterior pathogen has not yet been eliminated, and purgation should not be used.
It states: If the exterior has resolved but internal stagnation remains, presenting with great fullness, great solidity, and hardness, with dry fecal matter, slow purgation can be used. Even if four or five days have passed, it will not cause harm. However, if purgation is used when it is not indicated, internal deficiency will allow heat to enter, leading to diarrhea with accompanying heat (Xie Re Sui Li) and various forms of irritability, which are countless. Mild cases will worsen, and severe cases will result in death. Commentary: This clause explains that only when there is no exterior syndrome and internal hardness and fullness exist can purgation be used. This emphasizes that purgation should not be used lightly. Light or careless purgation causes significant harm.
It states: In Taiyang disease, if heat binds in the Bladder (Pang Guang), the patient may appear manic. If blood discharges spontaneously, the patient recovers. If the exterior has not resolved, do not attack; first resolve the exterior. Once the exterior is resolved, if there is only urgency and binding in the lower abdomen, then attack is permissible, and Tao Ren Chengqi Tang is appropriate.
First, in cases of cold damage requiring purgation, pill medicines should not be used, as pills cannot cleanse heat pathogens and instead damage healthy Qi. Furthermore, in treating cold damage where heat has transmitted to the interior, after administering purgative decoctions, approximately one sheng of bran fried with salt should be wrapped in silk cloth and applied to the patient's abdomen. Gently ironing/warming this area helps the medicinal qi move with heat, ensuring easier bowel movement.
Second, there are pulse conditions where purgation is contraindicated. As stated in the *Shanghan Lun*: In cold damage, if the pulse is faint (Wei) and there is aversion to cold, this indicates deficiency of both Yin and Yang. Do not induce sweating, vomiting, or purgation. If the Cun (inch) position pulse is floating and large, and the physician incorrectly uses purgation, this is a major error. If the Guan (middle) position pulse is weak, indicating deficient Stomach Qi with heat, strong purgation should not be used; removing the heat will lead to the onset of cold. If the Chi (cubit) position pulse is choppy, weak, and powerless, purgation is contraindicated. Although hard stool requires purgation, if the pulse is slow and delayed, purgation is contraindicated because the interior Qi is not solid. A deficient and fine pulse contraindicates purgation. A floating pulse contraindicates purgation. A soggy (Ru) and weak pulse, where weakness is found at the Guan position, sogginess at the Cun position, wiry (Xian) at the upper part, and faint (Wei) at the lower part: Wiry indicates Yang movement, faint indicates Yin cold. Upper excess and lower deficiency suggest a desire for warmth. Faint and wiry indicate deficiency; the deficient should not be purged. A floating and large pulse: Floating indicates Qi excess, large indicates Blood deficiency. Blood deficiency means lack of Yin. If solitary Yang descends into the Yin regions, and the physician mistakes this for heat, using toxic drugs to attack the Stomach, this results in double deficiency. The guest Yang will depart soon, leading to death with stools resembling sludge. A soggy and tight pulse: Soggy indicates微弱 Yang, tight indicates cold in the Ying level. Weak Yang allows Wind to invade the Wei level, causing fever and aversion to cold. Tight Ying and cold Stomach Qi cause slight vomiting and internal irritability. If the physician assumes great heat and uses diaphoresis to release the muscle layer, it leads to loss of Yang, deficiency-induced irritability, epigastric oppression and hardness, exhaustion of both exterior and interior, dizziness upon sudden rising, guest heat on the skin, bloating, and insomnia. Ignoring the cold Stomach Qi and tight cold at the Guanyuan acupoint, and using purgation instead of warming, makes recovery impossible. A prolonged rapid pulse indicates non-external pathogen; purgation is contraindicated. A fine and rapid pulse indicates non-excess pathogen; purgation is contraindicated. In Jie Xiong syndrome, if the pulse is floating and large, the pathogen has not entered the Fu organs; purgation is contraindicated, and purging leads to death. Generally, in cold damage, purgation must be used with extreme caution. If the pulse is powerless and the exterior syndrome has not ceased, do not recklessly administer decoctions; purgation in such cases is contrary to treatment principles.
Third, there are syndrome conditions where purgation is contraindicated. For example, in Taiyang disease, if the exterior syndrome has not resolved, purgation is contraindicated and constitutes a contrary treatment. In combined Taiyang and Yangming disease, if there is wheezing and chest fullness, the pathogen is in the exterior; purgation is contraindicated. In Yangming disease, if there is slight fever and aversion to cold, the exterior has not resolved; purgation is contraindicated. In Yangming disease, with tidal fever but initial hard stool followed by loose stool, purgation is contraindicated. In Yangming disease, with slight abdominal fullness, initial hardness followed by eventual looseness, this is not excess heat; purgation is contraindicated. In Yangming disease, if the fever is not tidal, Chengqi Tang should not be given. In Yangming disease, even with tidal fever, if the stool is not hard, Chengqi Tang should not be given. If there is no passage of flatus (Zhuan Shi Qi), the interior is not solid; purgation must be avoided with caution. In Yangming disease, if the epigastrium is rigid and full, do not attack; if purgation causes unceasing diarrhea, death ensues. Rigidity in the epigastrium indicates the pathogen is in the chest and diaphragm, not yet in the Fu organs; thus, purgation is contraindicated. In Zang Jie (Zang Binding) without Yang signs, without alternating chills and fever, with the patient appearing calm and a slippery coating on the tongue, purgation is contraindicated. If the patient desires to vomit, purgation is contraindicated. If vomiting is frequent, even with Yangming signs, purgation is contraindicated. Frequent vomiting indicates the disease is in the Upper Jiao; attacking the lower when the disease is in the upper is a path to defeat. In Yangming disease, if sweating is profuse with slight fever and aversion to cold, the exterior has not resolved, and the fever is not tidal; Chengqi Tang should not be given. In patients with dampness (Shi Jia), if purgation is used leading to sweating on the forehead, slight wheezing, and urinary difficulty, death ensues; persistent dysentery also leads to death. In Yangming disease, if the patient cannot eat, attacking the heat will cause hiccups (Yue); this is because of deficiency-cold in the Stomach. Due to the patient's inherent deficiency, attacking the heat inevitably causes hiccups. In cases of "Yin Strong, No Yang," even if the stool is hard, purgation is contraindicated; purging leads to undigested food in the stool and abdominal fullness. In cases of deficiency of both Yin and Yang with aversion to water, purgation leads to interior cold, loss of appetite, and undigested food in the stool. In cases of微弱 Yang, purgation is contraindicated; purging leads to epigastric oppression and hardness. In cases of aversion to cold, purgation is contraindicated. In cases of clear and profuse urination, Fire is not excessive; purgation is contraindicated. In all cases of Si Ni Jue (Four Extremities Cold/Reversal), purgation is contraindicated. In cases of throat obstruction, purgation is contraindicated. In cases of profuse sweating leading to loss of Yang and delirium, purgation is contraindicated. In all deficiency syndromes, purgation is contraindicated; purging leads to Yang deficiency and generation of cold. Zhang Zhongjing stated: In extreme cold with spontaneous sweating, the body becomes cold as ice. If the eyes are dull, speech is incessant, the mouth wants to speak but the tongue cannot extend forward, these are signs of death. In cases of Yin deficiency with water depletion, presenting with deficiency irritability and restlessness, purgation is contraindicated; severely depleting Yin leaves no hope for survival.