阴乘阳热血妄行，血犯气分不归经，血病及腑渗浊道，伤于脏者溢出清，热犯阳络上吐衄，
热侵阴络下失红，又有努劳成血病，血止仍嗽势多凶。
【注】凡失血之证，阳盛乘阴，则血为热迫，不能安于脉中，犯于气分，妄行不能归
入经脉也。若血病伤及于腑者，则血渗入肠胃之浊道，上行于咽，出而为吐为衄；下从
二便而出，为便为尿也。若血病伤及于脏者，则溢出于胸中之清道，上从喉出，而兼咳嗽；
下从精窍而出，为尿血也。夫血藏于脏内，行于脉中，流于躯壳之内，不可得而见也。非
损伤不能为病，而损之之因有三∶一曰热伤阳络，腑病也；热伤阴络，脏病也，宜以清
热为主。一曰努伤，宜以破逐为主。一曰劳伤，宜以理损为主。若日久血止，而咳嗽不
休者，主必死之证，故势多凶也。
衄血之候鼻干燥，身热不渴苦头疼，失表分汗麻桂治，内热犀角泻心清。
【注】衄血者，鼻中出血也。其候鼻中干
燥，身热不渴，苦头痛，是热伤阳络也。有因伤寒失汗衄血者，乃热郁于营。其身无汗，
宜以麻黄汤汗之；身有汗者，宜以桂枝汤解之，设无表病，因内热而衄者，宜以犀角地
黄汤清之。热盛者，四物三黄泻心汤泻之。外俱用发灰散，或黑栀子未吹鼻，其衄自止。
麻黄汤
麻黄 杏仁（炒去皮尖） 桂枝 甘草（生）
引用生姜，水煎服。
【方歌】伤寒失表营郁热，身热无汗血妄行，须用麻黄汤调治，桂枝麻黄杏草同。
桂枝汤
桂枝 芍药 甘草（炙） 生姜 大枣
水煎服。
犀角地黄汤
牡丹皮 白芍药 犀角 生地黄
水煎服，便硬者加川大黄。
【方歌】犀角地黄汤，治衄效非常，丹皮芍犀地，便秘加大黄。
四物三黄泻心汤
川芎 当归（酒洗） 生地黄 赤芍药 黄芩 黄连 川大黄（酒洗）
水煎服。
【方歌】四物三黄泻心汤，热盛吐衄功最良，芎归生地赤芍药，黄芩黄连川大黄。
阴气乘袭阳气，导致血热妄行，血液侵犯气分，不能回归经脉。若血病波及六腑，则渗入排泄浊液的通道；若损伤五脏，则从清窍溢出。热邪侵犯阳络，引起上部吐血、鼻衄；热邪侵袭阴络，引起下部便血、尿血。另有因过度用力或劳累导致的血证，若出血停止后仍持续咳嗽，病情多属凶险。
【注】凡是失血的病症，若是阳气亢盛乘袭阴分，血液就会受热逼迫，无法安守于脉管之中，侵犯气分，妄行而不能归入经脉。如果血病伤及六腑，血液就会渗入肠胃等排泄浊液的通道，向上经咽喉吐出，表现为吐血或鼻衄；向下从大小便排出，表现为便血或尿血。如果血病伤及五脏，血液就会溢出于胸中清肃的通道，向上经喉咙咳出，并伴有咳嗽；向下从尿道排出，表现为尿血。血液藏于脏腑之内，运行于脉管之中，流动在躯体内部，通常不可见。若非外伤损伤就不会致病，而致损的原因有三种：一是热邪损伤阳络，属于腑病，治疗应以清热为主；二是热邪损伤阴络，属于脏病，治疗也应以清热为主。二是努劳（过度用力）损伤，治疗应以破瘀逐血为主。三是劳倦损伤，治疗应以调理虚损为主。如果病程日久，虽然出血停止，但咳嗽不止，这是主死之证，所以病情大多凶险。
鼻衄的症状表现为鼻腔干燥，身体发热但不口渴，且痛苦于头痛。若因表证未解需发汗者，可用麻黄汤或桂枝汤治疗；若为内热所致，则用犀角地黄汤清热泻火。
【注】鼻衄是指鼻子出血。其症状表现为鼻腔干燥，身体发热但不口渴，且痛苦于头痛，这是热邪损伤阳络的表现。有因伤寒失于发汗而导致鼻衄的，这是因为热邪郁结在营分。如果患者身上无汗，宜用麻黄汤发汗解表；如果身上有汗，宜用桂枝汤解肌发表。如果没有表证，而是因内热导致鼻衄的，宜用犀角地黄汤清热凉血。若热势炽盛，可用四物三黄泻心汤泻火。外部均可使用发灰散，或将黑栀子研末吹入鼻腔，鼻衄自然停止。
麻黄汤
药材：麻黄、杏仁（炒制去皮尖）、桂枝、甘草（生用）。
用法：加入生姜为引，用水煎服。
【方歌】伤寒失于发汗导致营分郁热，身体发热无汗导致血液妄行，必须用麻黄汤来调治，由桂枝、麻黄、杏仁、甘草组成。
桂枝汤
药材：桂枝、芍药、甘草（炙用）、生姜、大枣。
用法：用水煎服。
犀角地黄汤
药材：牡丹皮、白芍药、犀角、生地黄。
用法：用水煎服，若大便干硬者，加川大黄。
【方歌】犀角地黄汤，治疗鼻衄效果非凡，由丹皮、芍药、犀角、地黄组成，便秘加大黄。
四物三黄泻心汤
药材：川芎、当归（酒洗）、生地黄、赤芍药、黄芩、黄连、川大黄（酒洗）。
用法：用水煎服。
【方歌】四物三黄泻心汤，治疗热盛导致的吐血鼻衄功效最佳，由川芎、当归、生地黄、赤芍药、黄芩、黄连、川大黄组成。
Yin invading Yang causes blood heat and reckless movement; blood invades the Qi level and fails to return to the meridians. If blood disease affects the Fu organs, it seeps into the turbid pathways of excretion; if it injures the Zang organs, it overflows from the clear orifices. Heat attacking the Yang collaterals leads to upper hematemesis and epistaxis; heat invading the Yin collaterals leads to lower hematochezia and hematuria. There are also blood diseases caused by strain and labor; if coughing persists after bleeding stops, the prognosis is often ominous.
[Note] In all cases of hemorrhage, if Yang excess invades Yin, blood is forced by heat and cannot remain within the vessels, invading the Qi level and moving recklessly without returning to the meridians. If blood disease injures the Fu organs, blood seeps into the turbid pathways of the intestines and stomach, ascending through the pharynx to be vomited as hematemesis or epistaxis; descending through the bowels and bladder to appear as hematochezia or hematuria. If blood disease injures the Zang organs, blood overflows from the clear pathways of the chest, ascending through the larynx accompanied by coughing; descending through the urethra to appear as hematuria. Blood is stored within the Zang organs, circulates within the vessels, and flows within the body shell, normally invisible. Disease does not occur without injury, and there are three causes of injury: first, heat injuring the Yang collaterals (Fu organ disease) and heat injuring the Yin collaterals (Zang organ disease), both should be treated primarily with clearing heat; second, injury from strain, which should be treated primarily with breaking stasis and expelling blood; third, injury from fatigue/labor, which should be treated primarily with regulating deficiency. If, after a long duration, bleeding stops but coughing continues, it indicates a fatal condition, hence the prognosis is often ominous.
The signs of epistaxis include dry nasal passages, fever without thirst, and distressing headache. If due to unresolved exterior syndrome requiring sweating, treat with Mahuang Tang (Ephedra Decoction) or Guizhi Tang (Cinnamon Twig Decoction); if due to internal heat, clear with Xijiao Dihuang Tang (Rhinoceros Horn and Rehmannia Decoction).
[Note] Epistaxis refers to bleeding from the nose. Its signs include dry nasal passages, fever without thirst, and distressing headache, indicating heat injuring the Yang collaterals. Some cases of epistaxis arise from failure to sweat in Shanghan (Cold Damage), where heat is constrained in the Ying (Nutritive) level. If the body has no sweat, use Mahuang Tang (Ephedra Decoction) to induce sweating; if the body has sweat, use Guizhi Tang (Cinnamon Twig Decoction) to resolve the exterior. If there is no exterior syndrome but epistaxis occurs due to internal heat, use Xijiao Dihuang Tang (Rhinoceros Horn and Rehmannia Decoction) to clear heat. If heat is excessive, use Siwu Sanhuang Xiexin Tang (Four Substances and Three Yellows Xiexin Decoction) to purge fire. Externally, apply Fahuisan (Hair Ash Powder) or black Zhizi powder insufflated into the nose, and the bleeding will stop naturally.
Mahuang Tang (Ephedra Decoction)
Ingredients: Ephedrae Herba (Mahuang, 麻黄), Armeniacae Semen Amarum (Xingren, 杏仁 - stir-fried, skin and tip removed), Cinnamomi Ramulus (Guizhi, 桂枝), Glycyrrhizae Radix et Rhizoma (Gancao, 甘草 - raw).
Usage: Add Zingiberis Rhizoma Recens (Shengjiang, 生姜) as a guide, decoct in water and take orally.
[Formula Song] Cold damage with failed sweating leads to Ying-level constraint and heat; fever and anhidrosis cause blood to move recklessly. One must use Mahuang Tang for treatment, composed of Cinnamon Twig, Ephedra, Apricot Seed, and Licorice.
Guizhi Tang (Cinnamon Twig Decoction)
Ingredients: Cinnamomi Ramulus (Guizhi, 桂枝), Paeoniae Radix (Shaoyao, 芍药), Glycyrrhizae Radix et Rhizoma (Gancao, 甘草 - honey-fried), Zingiberis Rhizoma Recens (Shengjiang, 生姜), Jujubae Fructus (Dazao, 大枣).
Usage: Decoct in water and take orally.
Xijiao Dihuang Tang (Rhinoceros Horn and Rehmannia Decoction)
Ingredients: Moutan Cortex (Mudanpi, 牡丹皮), Paeoniae Radix Alba (Baishaoyao, 白芍药), Rhinocerotis Cornu (Xijiao, 犀角), Rehmanniae Radix Preparata (Shengdihuang, 生地黄).
Usage: Decoct in water and take orally. If stool is hard, add Rhei Radix et Rhizoma (Chuan Dahuang, 川大黄).
[Formula Song] Xijiao Dihuang Tang is extremely effective for treating epistaxis, composed of Moutan Bark, Paeonia, Rhinoceros Horn, and Rehmannia; add Rheum for constipation.
Siwu Sanhuang Xiexin Tang (Four Substances and Three Yellows Xiexin Decoction)
Ingredients: Chuanxiong Rhizoma (Chuanxiong, 川芎), Angelicae Sinensis Radix (Danggui, 当归 - wine-washed), Rehmanniae Radix Preparata (Shengdihuang, 生地黄), Paeoniae Radix Rubra (Chishaoyao, 赤芍药), Scutellariae Radix (Huangqin, 黄芩), Coptidis Rhizoma (Huanglian, 黄连), Rhei Radix et Rhizoma (Chuan Dahuang, 川大黄 - wine-washed).
Usage: Decoct in water and take orally.
[Formula Song] Siwu Sanhuang Xiexin Tang is most excellent for treating hematemesis and epistaxis due to excessive heat, composed of Chuanxiong, Angelica, Rehmannia, Red Peony, Scutellaria, Coptis, and Rheum.