经义
阴络伤，血内溢，血内溢则后血。○结阴者，便血一升，再结二升，三结三升。（《素问》）
哲言
邪在五脏，则阴脉不和，阴脉不和，则血留之。结阴之病，以阴气内结，不得外行，血无所禀，渗入
肠间，故便血也。（骆龙吉）
纯下清血者，风也；色如烟尘者，湿也；色黯者，寒也；鲜红者，热也；糟粕相混者，食积也；遇劳频
发者，内伤元气也；后重便减者，湿毒蕴滞也；后重便增者，脾元下陷也；跌伤便黑者，瘀也；先吐后便者，
顺也。（《见闻录》）
肠风、脏毒、便血、肠 四者，证虽相似而各有辨。肠风，
由邪气外入，随感随见，所下清血而色鲜，必在粪前；脏毒，由蕴积热毒，久而始见，所下浊血而色黯，必在
粪后；便血，由湿热虚风，所下之血或清或浊，亦不论粪前粪后；肠 ，则客气盛而正气衰，所以血与水谷齐
出，不可不详审而治。○无故忽然泻下恶血，名曰心绝，难治。（《仁斋直指》）
人身之血，有阴有阳。阳血者，顺气而行，循流脉中，调和五脏，洒陈六腑，谓之营血；阴血者，居于
络脉，专守脏腑，滋养神气，濡润筋骨。若其脏感内外之邪伤，则或循经之阳血，至其伤处，为邪所阻，漏泄
经外；或居络之阴血，因着留之邪辟裂而出，则皆渗入肠胃而泄矣。俗见下血，率以肠风名之，不知风乃六淫
中之一耳，或风有从肠胃经脉而入客者，或肝经风木之邪内乘于肠胃者，则可谓之肠风。其他不因风邪，而肠
胃感受火、热二淫，与寒、燥、湿怫郁其气，及饮食用力过度，伤其阴络之血者，亦谓之肠风可乎？许学士谓∶
下清血，色鲜者，肠风也；血浊而色黯者，脏毒也；肛门射如血线者，脉痔也。滑伯仁云∶肠风，则足阳明
积热久而为风，风有以动之也；脏毒，则足太阴积热久而生湿，从而下流也。风则阳受之，湿则阴受之。《三因
方》五痔、脏毒、肠风之辨甚详。脏毒、肠风之血，出于肠脏间；五痔之血，出于肛门蚀孔处。治各不同。
（《证治准绳》）
肠风下血者何也？凡人肠皆有脂裹之，脂浓则肠实而安，肠中本无血，缘有风，或有热，以消其脂，则
肠遂薄，而身中之血乃得渗入耳。
便血与肠 ，本非同类。盖便血者，大便多实，而血自下也；肠 者，因泻利而见脓血，即痢疾也。
且便血有夙疾，而肠 惟新邪，尤为易辨。须详察大便之燥、泄如何？庶不致误。然多酒之人，必多溏泄，亦
多便血，又不可因泄而作肠 也。○大便下血，多由肠胃之火。盖大肠、小肠皆属于胃，但血在便前者，其
来近，或在广肠，或在肛门；血在便后者，其来远，或在小肠，
或在于胃。虽血之妄行由火者多，然有脾胃阳虚而不能统血者；有气陷而血亦陷者；有便久滑泄而血因以动者；
有风邪结于阴分而为便血者。大都有火者多因血热，无火者多因虚滑，治者当知虚实之要。（张景岳）
补编
下血，先便后血，此远血也，黄土汤主之。○下血，先血后便，此近血也，赤小豆当归散主之。（《金匮》）
下血因火者，宜清热为主，惟约营煎最佳，次则地榆散、槐花散。若热在脾胃小肠之间，而火之甚者，宜
抽薪饮；若素以阳脏多火，而脏毒下血，久不愈者，宜防风黄芩丸；酒毒淫热结蓄大肠下血者，宜约营煎、槐
角丸。若但以寒湿下血者，宜二术煎，或四君子汤，或葛花解酲汤。脾胃气虚，而大便下血者，其血不甚鲜红，
或紫或黑，此阳败而然，故多无热证。盖脾统血，脾虚则不能收摄；脾化血，脾虚则不能运化。是皆血无所主，
因而脱陷妄行，速宜温补脾胃，以寿脾煎、理中汤、养中煎、归脾汤；气陷不举而血不止者，宜补中益气汤、
举元煎。○血滑不止者，或因病久而滑，或因年衰而滑，或因气虚而滑，或因误用攻击以致气陷而滑。凡动血之
初，多由于火，及火邪既衰，而仍不止者，非虚即滑也。凡此皆当以固涩为主，宜胜金丸、香梅丸。然血滑
不止，多由气虚，宜以人参汤送之，或补中益气汤、归脾汤、举元煎、理中汤加乌梅、文蛤、五味子之类主之。（张景岳）
便血一证，古有肠风、脏毒、脉痔之分，其见不外乎风淫肠胃、湿热伤脾二义，不若《内经》谓阴络伤及
结阴之旨为精切，仲景之先便后血、先血后便之文尤简括也。阴络即脏腑隶下之络，结阴是阴不随阳之征，以
先后分别其血之远近，就远近可决其脏腑之性情，庶不致气失统摄，血无所归，如漏卮不已耳。肺病致燥涩，
宜润宜降，如桑麻丸及天冬、地黄、银花、柿饼之类；心病则火燃血沸，宜清宜化，如竹叶地黄汤及补心丹之
类；脾病必
湿滑，宜燥宜升，如茅术理中汤及益气汤之类；肝病有风阳痛迫，宜柔宜泄，如驻车丸及甘酸和缓之剂；肾
病见形消腰折，宜补宜填，如虎潜丸及理阴煎之剂；胆逆则木火煽营，有桑叶、山栀、柏子、丹皮之清养；大
肠为燥腑，每多湿热风淫，如辛凉苦燥之治；胃为水谷之海，多气多血之乡，脏病腑病无不兼之，宜补宜和，
应寒应热，难以拘执。若努力损伤者，通补为主；膏粱蕴积者，清疏为宜。痔疮则滋燥兼投，中毒须知寒热。
余如黑地黄丸以治脾湿肾燥；天真丸以大补真气真精；平胃、地榆之升降脾胃；归脾之守补心脾；斑龙○以温
煦奇督；建中之救复生阳；枳、术之疏补中土；禹粮、赤脂以堵截阳明；五仁汤复从前之肠液；养荣法善病后
之元虚。此皆祖古方而运以匠心，为后学之津梁也。（《临证指南》）
便血下久，则涣散无统，药中须兼用乌梅为妙。盖乌梅味酸，酸以收之，如今人染红用红花，非此不得颜
色。○肠风下血，用炮姜佐血药者，以血见黑则止，亦水火既济之理。
脉候
尺脉芤涩，关脉微缓，俱为便血。脉小留连者生，数疾浮大者死。右关沉紧，是饮食伤脾，不能摄血而下
走也；右寸浮洪，是积热肺经，下传大肠而便血也。（《证治汇补》）
选案
一人患肠风下血，久服四物、芩、连、槐花，屡发不止，面色萎黄，诊脉浮缓。此土虚风湿交乘也。治用
苍术、茯苓、参、 、升、柴、防风，四剂而血止，改用十全大补汤调理而愈。（李士材）
韩晋度患痛泻下血，或用香连丸，遂饮食艰进，少腹急结，小便癃闭，面色萎黄，昼夜去血五十余度，脉
沉细紧，所下之血
瘀晦如苋汁。与理中汤加肉桂，一剂溺通，少腹即宽，再剂血减食进，四剂泻止三、四次，更与补中益气加炮
姜而康。（张路玉）
附方
治肠风下血方 用猪肠一根洗净，装入炒槐花，两头线扎，瓦罐醋煮，杵丸，每服三十丸，温酒送下，奇验。
又方 用豆腐浆加醋二、三匙，空心服之。腐浆清火，醋敛血故耳。
又方 用臭椿树根皮、党参二味，等分，烘干研末，大枣煮去皮核，取肉杵丸，每早服三钱，开水下，治
便血日久，神效。
[Classical Theory]
When the Yin collaterals (fine collaterals distributed in the internal organs) are injured, blood overflows within the body; when blood overflows within the body, it results in hematochezia. ○ In Jieyin disease (a condition characterized by internal knotting of Yin qi), each episode involves the passage of one sheng of blood in stool; a second episode involves two shengs; a third episode involves three shengs. (*Su Wen*)
[Masters' Discourses]
When pathogenic factors invade the Zang organs, the Yin meridians become disharmonious; when the Yin meridians are disharmonious, blood stagnates therein. In Jieyin disease, internal knotting of Yin qi prevents its outward circulation; blood loses its control and seeps into the intestines, thus causing hematochezia. (Luo Longji)
Purely clear blood discharged indicates Wind pathogen; blood resembling smoke or dust indicates Dampness; dark color indicates Cold; bright red color indicates Heat; blood mixed with fecal matter indicates Food Stagnation; frequent recurrence after exertion indicates Internal Injury to Yuan Qi; tenesmus relieved by defecation indicates accumulation and stagnation of Damp-Toxin; tenesmus aggravated by defecation indicates sinking of Spleen Yuan; black stool after trauma indicates Blood Stasis; hematemesis followed by hematochezia is a favorable progression. (*Jianwen Lu*)
Changfeng (Intestinal Wind), Zangdu (Visceral Toxin), Bianxue (Hematochezia), and Changpi (Dysentery) present similar symptoms but have distinct characteristics. Changfeng arises from external pathogens invading; symptoms appear immediately upon contraction; the discharged blood is clear and bright red, typically appearing before the stool. Zangdu arises from accumulated heat-toxin; symptoms manifest only after a long time; the discharged blood is turbid and dark, typically appearing after the stool. Bianxue arises from Damp-Heat or Deficient Wind; the discharged blood may be clear or turbid, regardless of whether it appears before or after the stool. Changpi occurs when external pathogens are excessive and Zheng Qi (Upright Qi) is deficient, resulting in blood discharging together with food and fluids; this requires careful differentiation and treatment. ○ Sudden discharge of foul-smelling black blood without cause is called Heart Exhaustion (Xin Jue) and is difficult to treat. (*Ren Zhi Zhi Zhi*)
Human blood is divided into Yin blood and Yang blood. Yang blood flows with Qi, circulates within the vessels, harmonizes the Zang organs, and distributes to the Fu organs; it is called Ying Blood (Nutritive Blood). Yin blood resides in the collaterals, guards the Zang organs, nourishes Shen Qi (Spirit Qi), and moistens sinews and bones. If the Zang organs are injured by internal or external pathogens, either the Yang blood following the meridians reaches the injury site, is blocked by pathogens, and leaks outside the vessels; or the Yin blood residing in the collaterals ruptures due to lingering pathogens, both leading to seepage into the intestines and stomach for discharge. Laypeople often attribute lower bleeding to Changfeng, not knowing that "Wind" is merely one of the Six Excesses. It can only be termed Changfeng if Wind pathogen enters via the intestinal meridians or if Liver Wind Wood pathogen invades internally. Other cases not caused by Wind, but by Fire or Heat excesses affecting the intestines and stomach, or by constraint of Cold, Dryness, or Dampness, or by dietary excess and strain injuring the Yin collaterals, should not simply be called Changfeng. Xu Xueshi stated: Clear, bright red blood indicates Changfeng; turbid, dark blood indicates Zangdu; blood shooting like a thread from the anus indicates Mai Zhi (Vascular Hemorrhoids). Hua Borren stated: Changfeng arises from long-standing accumulated heat in the Foot-Yangming Stomach meridian transforming into Wind, which agitates the blood; Zangdu arises from long-standing accumulated heat in the Foot-Taiyin Spleen meridian generating Dampness, which flows downward. Wind affects Yang meridians; Dampness affects Yin meridians. *San Yin Fang* distinguishes Wu Zhi (Five Hemorrhoids), Zangdu, and Changfeng in detail. The blood of Zangdu and Changfeng originates between the intestines and viscera; the blood of Wu Zhi originates at the eroded pores of the anus. Treatments differ. (*Zhengzhi Zhunsheng*)
What is Changfeng hematochezia? Human intestines are wrapped in fat; thick fat ensures intestinal integrity and stability, and normally there is no blood in the intestines. However, Wind or Heat consumes this fat, thinning the intestinal wall, allowing body blood to seep in.
Bianxue and Changpi are not the same category. Generally, patients with Bianxue have dry, solid stools with spontaneous blood discharge; patients with Changpi have pus and blood due to diarrhea/dysentery, i.e., Dysentery. Bianxue often has a chronic history, whereas Changpi involves new pathogenic invasion, making them easy to distinguish. One must carefully examine whether the stool is dry or loose to avoid misdiagnosis. However, habitual drinkers often have loose stools and also suffer from hematochezia; one must not mistake diarrhea for Changpi. ○ Lower bleeding usually stems from Fire in the intestines and stomach. Since Large and Small Intestines belong to the Stomach, blood appearing before stool indicates a proximal source, such as the Rectum or Anus; blood appearing after stool indicates a distal source, such as the Small Intestine or Stomach. Although reckless bleeding is mostly due to Fire, there are cases of Spleen-Stomach Yang deficiency failing to control blood, Qi sinking causing blood to sink, prolonged slippery diarrhea triggering blood movement, and Wind pathogen knotting in the Yin division causing hematochezia. Generally, Fire cases stem from Blood Heat; non-Fire cases stem from Deficiency and Slipperiness. Practitioners must understand the key of Deficiency and Excess. (Zhang Jingyue)
[Supplement]
Lower bleeding where stool precedes blood is Distal Bleeding (Yuan Xue), treated primarily with Huangtu Tang (Yellow Earth Decoction). ○ Lower bleeding where blood precedes stool is Proximal Bleeding (Jin Xue), treated primarily with Chixiaodou Danggui San (Adzuki Bean and Angelica Sinensis Powder). (*Jin Gui Yao Lue*)
For lower bleeding due to Fire, clearing Heat is primary; Yueying Jian is best, followed by Diyü San and Huaihua San. If heat is between the Spleen/Stomach and Small Intestine with severe Fire, Chouxin Yin is indicated. For constitutions with abundant Yang and Fire, suffering from chronic Zangdu hematochezia, Fangfeng Huangqin Wan is indicated. For lower bleeding due to alcohol toxin and excessive heat accumulating in the Large Intestine, Yueying Jian or Huaijiao Wan is indicated. For lower bleeding due solely to Cold-Damp, Erzhu Jian, Sijunzi Tang, or Gehua Jiecheng Tang is indicated. For Spleen-Stomach Qi deficiency causing lower bleeding, the blood is not bright red but purple or black, indicating Yang failure; thus, Heat signs are usually absent. The Spleen controls blood; deficiency leads to inability to contain it. The Spleen transforms blood; deficiency leads to inability to transport. These result in blood losing its master and leaking recklessly; rapid warming and tonification of Spleen-Stomach is needed using Shoupi Jian, Lizhong Tang, Yangzhong Jian, or Guipi Tang. For Qi sinking failing to lift with persistent bleeding, Buzhong Yiqi Tang or Juyuan Jian is indicated. ○ Slippery, unceasing bleeding may result from chronic illness, aging, Qi deficiency, or misuse of attacking drugs causing Qi sinking. Initial bleeding is mostly due to Fire; if it persists after Fire subsides, it is Deficiency or Slipperiness. Such cases require astringency as primary treatment, using Shengjin Wan or Xiangmei Wan. However, slippery bleeding is mostly due to Qi deficiency; it is advisable to administer with Renshen Tang, or use Buzhong Yiqi Tang, Guipi Tang, Juyuan Jian, or Lizhong Tang plus Wumei, Wenhai, or Wuweizi. (Zhang Jingyue)
The syndrome of hematochezia was traditionally divided into Changfeng, Zangdu, and Mai Zhi, manifesting mainly as Wind invading intestines/stomach or Damp-Heat injuring Spleen. This is less precise than the *Neijing*'s concept of Yin collateral injury and Jieyin, and less concise than Zhang Zhongjing's distinction of stool-before-blood vs. blood-before-stool. Yin collaterals refer to collaterals subordinate to Zang organs; Jieyin signifies Yin failing to follow Yang. Differentiating proximity based on sequence helps determine organ nature, preventing loss of Qi control and blood wandering like an unstoppered vessel. Lung disease causing dryness requires moistening and descending, e.g., Sangma Wan, Tian Dong, Di Huang, Yin Hua, Shi Bing. Heart disease causing fire boiling blood requires clearing and resolving, e.g., Zhuye Dihuang Tang or Buxin Dan. Spleen disease involving damp slipperiness requires drying and ascending, e.g., Maozhu Lizhong Tang or Yiqi Tang. Liver disease with Wind-Yang pain requires softening and draining, e.g., Zhuche Wan or sour-sweet mild agents. Kidney disease with emaciation and lumbar weakness requires tonifying and filling, e.g., Hujian Wan or Liyin Jian. Gallbladder rebellion stirring Wood-Fire in Ying blood requires clearing/nourishing with Sang Ye, Shan Zhi, Bai Zi, Dan Pi. Large Intestine is a dry Fu organ, prone to Damp-Heat/Wind, requiring pungent-cool and bitter-dry treatments. Stomach is the sea of water/grain, rich in Qi/blood, accommodating Zang/Fu diseases, requiring tonification/harmonization, cold/heat adjustments, avoiding rigidity. Effort-induced injury requires general tonification; rich diet accumulation requires clearing/dispersing. Hemorrhoids require combining moistening and drying; toxins require distinguishing cold/heat. Others include Hei Dihuang Wan for Spleen damp/Kidney dryness; Tianzhen Wan for tonifying true Qi/essence; Pingwei San/Diyu for regulating Spleen/Stomach Qi; Guipi Tang for guarding/tonifying Heart/Spleen; Banlong Wan for warming extraordinary/Du vessels; Jianzhong Tang for restoring Sheng Yang; Zhishi/Baizhu for dispersing/tonifying middle Jiao; Yuliang/Shizhi for blocking Yangming; Wuren Tang for restoring intestinal fluid; Yangrong method for post-illness Yuan deficiency. These adapt ancient formulas with ingenuity, serving as bridges for learners. (*Linzheng Zhinan*)
For prolonged hematochezia causing dispersion and lack of control, adding Wumei (Mume Fruit) to prescriptions is excellent. Its sour taste astringes, akin to using Honghua (Safflower) for dyeing; without it, color cannot be achieved. ○ For Changfeng hematochezia, using Paojiang (Roasted Ginger) assisting blood herbs works because blood stops when turned black, reflecting the principle of Water-Fire mutual interaction.
[Pulse Diagnosis]
Cun Kou pulse at Chi position is hollow and choppy; Guan position is slightly slow; both indicate hematochezia. A small, lingering pulse indicates survival; a rapid, rapid, floating, and large pulse indicates death. Right Guan deep and tight indicates dietary injury to Spleen failing to control blood, causing downward flow; Right Cun floating and surging indicates accumulated heat in Lung meridian transmitting to Large Intestine causing hematochezia. (*Zhengzhi Huibu*)
[Selected Cases]
A patient suffered from Changfeng hematochezia, taking Siwu Tang, Huang Qin, Huang Lian, and Huaihua repeatedly without cessation. Complexion was sallow; pulse was floating and slow. This indicated Spleen deficiency with Wind-Damp interplay. Treatment used Cang Zhu, Fu Ling, Ren Shen, Huang Qi, Sheng Ma, Chai Hu, and Fang Feng. After four doses, bleeding stopped; switched to Shiquan Dabu Tang for recovery. (Li Shicai)
Han Jin Du suffered from painful diarrhea with hematochezia. Use of Xianglian Wan led to difficulty eating, lower abdominal urgency, urinary retention, sallow complexion, and bleeding over fifty times day and night. Pulse was deep, fine, and tight; discharged blood was dark and turbid like Amaranthus juice. Prescribed Lizhong Tang plus Rou Gui. After one dose, urination resumed and abdomen relaxed; after two doses, bleeding decreased and appetite improved; after four doses, diarrhea stopped 3-4 times daily. Finally, Buzhong Yiqi Tang plus Paojiang restored health. (Zhang Luyu)
[Attached Formulas]
Formula for Changfeng Hematochezia: Clean one pig intestine, fill with fried Huaihua, tie ends with thread, boil in vinegar in a clay pot, pound into pills. Take 30 pills with warm wine. Highly effective.
Another Formula: Drink tofu milk with 2-3 spoons of vinegar on an empty stomach. Tofu milk clears fire; vinegar astringes blood.
Another Formula: Equal parts of Chou Chun Pi (Ailanthus Bark) and Dang Shen, dried and powdered. Boil dates, remove skin/pits, mash pulp, mix with powder to make pills. Take 3 qian every morning with boiled water. Highly effective for chronic hematochezia.