【歌】肠风脏毒从何别？肠胃停寒与蓄热。血浊色黯脏毒因，蕴毒于中几 荚。肠风血色清且鲜，外邪随
感而随泄。
【论】人之肠胃不虚，则邪气无由而入。或坐卧风湿，醉饱房劳，生冷停寒，酒面积热，以致荣血失道，
渗入于大肠之经，此肠风、脏毒之所由作也。故挟热下血暴发者，则血色清鲜，腹中有痛；若挟寒而下血兼积
久者，则血色凝浊而色黯，腹内微痛。故暴病则为肠风，盖肠风者，邪从外入，随感而随见是也；积久始发，
浊者为脏毒，盖脏毒者，久积其毒而始发是也。有先血后便者，其血来也近；先便后血者，其血来也远。俗谓
粪前、粪后，非也。若脏毒证积热日久，
忽郁于寒，实非寒也，不可以标寒而用热剂也。
肠风
丹溪云∶肠风独在胃、大肠出。若兼风者，苍术、秦艽、香附之类。便血久远伤血致虚，并麻风、癣疮见
于面者，椿皮丸。又方肠风下血，香附一两、枳壳七钱、芎、归各五钱、槐角、甘草各二钱，姜、枣煎服。
椿皮丸
治肠风致虚。
龟板（二两，酥炙） 升麻（五钱） 香附（五钱） 白芍药（两半） 侧柏叶（一两） 椿根白皮（七钱半）
末之，粥丸桐子大，每服六十丸，以四物汤加白术、黄连、甘草、陈皮作末调汤送下。
脏毒
寒食积毒于肠，日久始发，曰脏毒。积热者，三黄丸。协湿，地榆丸。协寒，败毒散。次以芎归汤随其寒
热而调之。热加茯苓、槐花；寒加木香、茯苓。（方见头痛。）收功，四物汤加参、 、槐角。
三黄丸
治积热便血。
苍术（一两半） 陈皮（一两半） 黄连（七钱半） 连翘（半两）
末之，生地捣烂糊丸，桐子大，白汤下。
地榆丸
治脏毒挟湿者。
白术（半两） 黄柏（炒，二钱） 生地黄（二钱） 白芍药（二钱） 地榆（二钱） 黄芩（炒，二钱）
香附（二钱）
共末，蒸饼为丸。
败毒散
治协寒便血。
羌活（一钱，去芦） 独活（一钱，去芦） 柴胡（一钱，去毛） 前胡（一钱，去芦） 枳壳（炒，八
分） 茯苓（八分，去皮） 川芎（七分） 甘草（五分，炙） 桔梗（八分，去芦）
姜三片，水二钟，煎一钟服。
[Song] How to differentiate between Intestinal Wind (Changfeng) and Visceral Toxin (Zangdu)? It lies in whether there is retained cold or accumulated heat in the intestines and stomach. Turbid blood with a dark color indicates Visceral Toxin, caused by toxin accumulation within; clear and bright blood indicates Intestinal Wind, where external pathogens are expelled immediately upon contraction.
[Discussion] If a person's intestines and stomach are not deficient, pathogenic factors have no way to enter. Whether due to sitting or lying in wind-dampness, excessive drinking and full meals, sexual exhaustion, retention of raw/cold foods leading to cold stagnation, or accumulation of alcohol and food leading to heat, causing the nutritive blood to lose its proper course and seep into the meridians of the large intestine, this is how Intestinal Wind and Visceral Toxin arise. Therefore, when bleeding from the anus occurs suddenly accompanied by heat, the blood is clear and bright, and there is abdominal pain; if bleeding occurs over a long duration accompanied by cold, the blood is coagulated, turbid, and dark, with slight internal abdominal pain. Thus, sudden illness is called Intestinal Wind, meaning the pathogen enters from outside and manifests immediately upon contraction; onset after a long duration with turbid blood is called Visceral Toxin, meaning the toxin accumulates for a long time before manifesting. Those who bleed before defecating have bleeding close to the anus; those who bleed after defecating have bleeding far from the anus. The common saying of "before stool" or "after stool" is incorrect. If Visceral Toxin involves long-standing accumulated heat that suddenly presents with cold symptoms, it is actually not true cold, and one should not use hot-pungent medicines based on superficial cold signs.
Intestinal Wind
Zhu Danxi stated: Intestinal Wind originates solely in the Stomach and Large Intestine. If accompanied by Wind, herbs such as Cangzhu (Atractylodis Rhizoma), Qinjiao (Gentianae Macrophyllae Radix), and Xiangfu (Cyperi Rhizoma) may be used. For chronic hematochezia damaging blood and causing deficiency, or for Leprosy (Mafeng) and Tinea (Xuanchuang) appearing on the face, Chunpi Wan (Toona Sinensis Bark Pill) is indicated. Another prescription for Intestinal Wind with hematochezia uses Xiangfu (Cyperi Rhizoma) 1 liang, Zhike (Aurantii Fructus Immaturus) 7 qian, Chuanxiong (Ligustici Chuanxiong Rhizoma) and Danggui (Angelicae Sinensis Radix) each 5 qian, Huaijiao (Sophorae Tonkinensis Fructus) and Gancao (Glycyrrhizae Radix et Rhizoma) each 2 qian, decocted with Shengjiang (Zingiberis Rhizoma Recens) and Dazao (Jujubae Fructus).
Chunpi Wan
Treats deficiency caused by Intestinal Wind.
Guiban (Testudinis Carapax et Plastrum, 2 liang, roasted with su) Shengma (Cimicifugae Rhizoma, 5 qian) Xiangfu (Cyperi Rhizoma, 5 qian) Baishao (Paeoniae Radix Alba, 1.5 liang) Cebaiye (Platycladi Cacumen, 1 liang) Chunpigenbaipi (Toonae Radicis Cortex, 7.5 qian). Grind into powder, mix with congee to form pills the size of Sophora seeds. Take 60 pills per dose, delivered with a decoction made from Sini Tang (Four Substances Decoction) added with Baizhu (Atractylodis Macrocephalae Rhizoma), Huanglian (Coptidis Rhizoma), Gancao (Glycyrrhizae Radix et Rhizoma), and Chenpi (Citri Reticulatae Pericarpium) ground into powder.
Visceral Toxin
Cold and food toxins accumulate in the intestines and manifest only after a long time, called Visceral Toxin. For accumulated heat, Sanhuang Wan (Three Yellows Pill) is used. For dampness, Diyue Wan (Sanguisorbae Pill) is used. For cold, Baidu San (Detoxifying Powder) is used. Subsequently, Xionggui Tang (Chuanxiong and Danggui Decoction) is used to regulate according to cold or heat patterns. Add Fuling (Poria) and Huaihua (Sophorae Flos) for heat; add Muxiang (Aucklandiae Radix) and Fuling (Poria) for cold. (Formula see Headache section). For recovery, Sini Tang (Four Substances Decoction) is used with added Renshen (Ginseng Radix et Rhizoma), Huangqi (Astragali Radix), and Huaijiao (Sophorae Tonkinensis Fructus).
Sanhuang Wan
Treats hematochezia due to accumulated heat.
Cangzhu (Atractylodis Rhizoma, 1.5 liang) Chenpi (Citri Reticulatae Pericarpium, 1.5 liang) Huanglian (Coptidis Rhizoma, 7.5 qian) Lianqiao (Forsythiae Fructus, half liang). Grind into powder, mix with fresh Shengdi Huang (Rehmanniae Radix) pounded into paste to form pills the size of Sophora seeds. Take with plain warm water.
Diyue Wan
Treats Visceral Toxin complicated by dampness.
Baizhu (Atractylodis Macrocephalae Rhizoma, half liang) Huangbai (Phellodendri Cortex, stir-fried, 2 qian) Shengdi Huang (Rehmanniae Radix, 2 qian) Baishao (Paeoniae Radix Alba, 2 qian) Diyue (Sanguisorbae Radix, 2 qian) Huangqin (Scutellariae Radix, stir-fried, 2 qian) Xiangfu (Cyperi Rhizoma, 2 qian). Grind into powder, use steamed wheat cake as binder to form pills.
Baidu San
Treats hematochezia complicated by cold.
Qianghuo (Notopterygii Rhizoma et Radix, 1 qian, remove lu) Duhuo (Angelicae Pubescentis Radix, 1 qian, remove lu) Chaihu (Bupleuri Radix, 1 qian, remove mao) Qianhu (Peucedani Radix, 1 qian, remove lu) Zhike (Aurantii Fructus Immaturus, stir-fried, 8 fen) Fuling (Poria, 8 fen, remove skin) Chuanxiong (Ligustici Chuanxiong Rhizoma, 7 fen) Gancao (Glycyrrhizae Radix et Rhizoma, 5 fen, honey-roasted) Jiegeng (Platycodonis Radix, 8 fen, remove lu). Add 3 slices of Shengjiang (Zingiberis Rhizoma Recens), 2 zhong of water, decoct to 1 zhong and take.