心火移热于小肠，小肠入于膀胱，膀胱热炽于小便，则小便赤涩，血随之。又肺受火邪之克，以致毒瓦斯
无从而泄，盖因失降下之故也。或生烦躁不宁者有之，不必专于利水，宜清金降火气
为要，用导赤散加生山栀、川连、升麻等药治之，火气既出，小便自然清利矣。
导赤散方∶
木通 麦冬 车前 生地 生甘草（一钱） 赤苓 生栀 生黄
苓滑石 泽泻 川柏 知母 加灯芯煎（以上各二钱）
盖溺血总系烈毒内攻也，况出自小肠乎，故五淋病惟浊血尤重，非下极清凉之药，难以缓其流，澄其源也。
淋症从溺窍来，浊症从精孔来，贝母六一散能分水道。
尿血即血淋也，溺血者，心与小肠实热也，可加贝母、前胡、石苇、牛膝各二钱。
血气下行，大便自无阻滞，苟热气燥结于下，毒火流住于大肠，以致津液干枯不得润滑，故大便有秘结
之症。苟不攻其胃则胃实，胃实则生谵语，腹胀目赤者有之。《经》云∶毒瓦斯归胃，胃气闭塞，喘急烦躁不免
矣。急用大黄、栝蒌仁、枳壳润下以去毒，外导亦可，加升麻提之更好，盖清气提上，而浊气自下也。
发热与见点并回后五六日之间作泻者，是泻火毒不泻元气也，切勿止之，《经》云∶毒以泻松，痛以利
减，回后泻至八九日外当用四苓散加升麻、槐花、桔梗、柴胡、栀子、黄连、车前、六一散、杏仁、条芩、
豆根、栝蒌仁，切勿用白术、木香健脾等药。泻出之物如鸡卵臭者，伤食也。宜用山楂、麦芽、槟榔、
川朴等味以消食积。
《经》云∶泄泻者，邪入于大肠，原进原出者，邪热不化谷也。盖因火性沸腾，不暇分消，故其出也。
泄泻大作，一切寒凉清解之药在所禁忌，然非所以概治热毒下痢之 症也。热毒太
甚，其毒不能尽行肌表；势必至于壅滑凝滞，所幸内实不受邪，侵注于大肠，大肠为传送之官，不至毒害迫
于其中，频频下痢，虽与泄泻相似，而实不同。此之泻者滑而不禁，彼则坚而闭塞，此之泻者溏而不实，
彼则凝结如胶漆。有纯下清水，或秽气不甚，或便塞难出，或腹痛烦躁不宁，重用芩连以清其火，稍加大
黄以攻毒而痢自止矣。若以泄泻治之，则左矣。《经》云∶热毒冲肠便自频，喜肠传送毒难侵。频频欲解仍难
塞，误认脾虚终内攻，久泻者饮食内停中气阻，转运失职脾困苦，纵然顺症亦淹迟，
内伤消积止泻吐，热退便塞须加升麻，一提而大小便自顺矣。
心火将热邪转移至小肠，小肠的热邪进而传入膀胱。若膀胱内热势炽盛导致小便赤红涩痛，血液便会随之而出。此外，肺脏受到火邪的克制，致使毒气无法通过正常途径排泄，这是因为肺气失于肃降的缘故。有的患者会出现烦躁不安的症状，此时不必专门使用利尿药物，关键在于清泻肺金之火，应使用导赤散加入生山栀、川连（黄连）、升麻等药物治疗。待火气排出后，小便自然就会清澈通利。
导赤散方剂组成：
木通、麦冬、车前子、生地、生甘草（一钱）、赤茯苓、生栀子、生黄芩、滑石、泽泻、川柏（黄柏）、知母，加灯芯草煎服（以上各二钱）。
尿血总归是烈性毒邪内攻所致，况且血液出自小肠，所以在五淋病中，伴有浊血的情况尤为严重，若非使用极清凉的药物，难以减缓出血之势并澄清源头。淋症是从尿道口排出的，浊症是从精窍排出的，贝母六一散能够分清水道。尿血即属于血淋范畴，溺血是由于心与小肠实热所致，可加入贝母、前胡、石苇、牛膝各二钱。
气血下行通畅，大便自然没有阻滞。如果热气燥结于下部，毒火滞留于大肠，导致津液干枯失去润滑作用，就会出现大便秘结的症状。如果不攻逐胃中的实热，会导致胃气壅实，胃实则会产生谵语，甚至出现腹胀、目赤等症状。《内经》云：“毒气归于胃，胃气闭塞，必然出现喘急和烦躁。”急需使用大黄、栝蒌仁、枳壳润下以祛除毒邪，外用导法也可以，加入升麻提升清气效果更好，因为清气上升，浊气自然下降。
在发热与出疹点并见以及回退后的五六天之间发生腹泻的，这是泻火毒而不伤元气，切勿强行止泻。《内经》云：“毒邪通过泻下而松解，疼痛通过通利而减轻。”回退后腹泻持续至八九日以外时，应当使用四苓散加入升麻、槐花、桔梗、柴胡、栀子、黄连、车前子、六一散、杏仁、条芩、豆根、栝蒌仁，切勿使用白术、木香等健脾药物。泻出的物质像鸡蛋臭味的，是伤食所致。宜用山楂、麦芽、槟榔、川朴（厚朴）等药物来消除食积。
《内经》云：“泄泻是因为邪气进入大肠，原样进原样出，这是邪热不能消化谷物的缘故。”这是因为火性沸腾，无暇分别消导，所以直接排出。当泄泻发作严重时，一切寒凉清解的药物都在禁忌之列，但这并不是用来概括治疗热毒下痢的方法。如果热毒过于严重，毒邪不能完全透发于肌表；势必造成壅滞滑腻凝滞，所幸体内正气尚实不受邪气侵扰，毒邪侵入注于大肠。大肠是传导之官，不至于让毒害逼迫其中，从而频频下痢。虽然这与泄泻相似，但实际上不同。这种痢疾的特点是滑脱不禁，而泄泻则是坚硬闭塞；这种痢疾是大便稀溏不成形，而泄泻则是凝结如胶漆。有的纯下清水，或秽气不重，或大便堵塞难出，或腹痛烦躁不安，应重用黄芩、黄连以清其火，稍加大黄以攻毒，痢疾自然停止。如果用治泄泻的方法来治疗，那就错了。《内经》云：“热毒冲犯肠道则排便频繁，喜恶在于肠道传导毒邪难以侵犯。频频想解却仍难塞住，误认为脾虚最终导致毒邪内攻。”久泻者饮食停滞于中焦阻碍中气，转运失职使脾脏困苦，即使是顺症也会拖延迟缓，内伤需消积止泻吐，热退后大便闭塞须加升麻，一提气则大小便自然顺畅。
The Heart Fire transfers heat to the Small Intestine (Xiaochang), and the heat from the Small Intestine enters the Bladder (Pangguang). If the Bladder is afflicted with intense heat causing redness and dysuria (red, painful, difficult urination), blood will follow. Furthermore, if the Lung (Fei) is constrained by Fire Evil, toxic vapors cannot be excreted normally due to the failure of Lung Qi to descend. Some patients may experience irritability and restlessness; in such cases, there is no need to focus solely on promoting diuresis. The key is to clear the Metal element and reduce Fire Qi. One should use Dao Chi San (Guide Out the Red Powder Decoction) added with Sheng Shan Zhi (Raw Gardenia Fruit), Chuan Lian (Coptis Rhizome), and Sheng Ma (Cimicifugae Rhizoma), among other herbs. Once the Fire Qi is expelled, urination will naturally become clear and smooth.
Dao Chi San Formula:
Tong Cao (Akebia Caulis), Mai Dong (Ophiopogonis Radix), Che Qian Zi (Plantaginis Semen), Sheng Di Huang (Rehmanniae Radix), Sheng Gan Cao (Glycyrrhizae Radix et Rhizoma - 1 qian), Chi Fu Ling (Poria Cocos with Red Core), Sheng Zhi Zi (Gardeniae Fructus), Sheng Huang Qin (Scutellariae Radix), Hua Shi (Talcum), Ze Xie (Alismatis Rhizoma), Chuan Bai (Phellodendri Cortex), Zhi Mu (Anemarrhenae Rhizoma), decocted with Deng Xin Cao (Junci Medullia) (all others at 2 qian each).
Hematuria is generally caused by fierce toxins attacking internally, especially since the blood originates from the Small Intestine. Therefore, among the Five Types of Strangury (Wu Lin), those accompanied by turbid blood are particularly severe. Only extremely cooling medicines can alleviate the flow and clarify the source. Strangury (Lin Zheng) discharges from the urinary orifice, while turbidity (Zhuo Zheng) discharges from the essence orifice; Bei Mu Liu Yi San (Fritillaria Six-to-One Powder) can separate the water pathways. Hematuria is equivalent to Blood Strangury (Xue Lin); strangury involving blood is due to Excess Heat in the Heart and Small Intestine. In such cases, one may add Bei Mu (Fritillariae Bulbus), Qian Hu (Peucedani Radix), Shi Wei (Pyrrosiae Folium), and Niu Xi (Achyranthis Bidentatae Radix), each at 2 qian.
When Qi and Blood descend smoothly, stool faces no obstruction. However, if hot qi causes dryness and accumulation in the lower jiao, and toxic fire stagnates in the Large Intestine (Dachang), body fluids become dry and lose lubrication, leading to constipation. If the Stomach (Wei) excess is not purged, Stomach excess will arise, potentially causing delirium, abdominal distension, and red eyes. The Classic states: "When toxins return to the Stomach and Stomach Qi becomes blocked, panting, urgency, and irritability are inevitable." Urgently use Da Huang (Rhei Radix et Rhizoma), Gua Lou Ren (Trichosanthis Semen), and Zhi Ke (Aurantii Fructus Immaturus) to moisten and purge to remove toxins. External suppository methods are also acceptable; adding Sheng Ma to lift Qi is even better, as lifting Clear Qi allows Turbid Qi to descend naturally.
Diarrhea occurring between the fifth and sixth day after fever, rash appearance, and resolution indicates the purging of Fire Toxin without damaging Yuan Qi; do not attempt to stop it abruptly. The Classic states: "Toxins are loosened through purgation, and pain is relieved through unblocking." If diarrhea persists for more than eight or nine days after resolution, Si Ling San (Four-Poria Powder) should be used with additions of Sheng Ma, Huai Hua (Sophorae Flos), Jie Geng (Platycodonis Radix), Chai Hu (Bupleuri Radix), Zhi Zi, Huang Lian, Che Qian Zi, Liu Yi San (Six-to-One Powder), Xing Ren (Armeniacae Semen Amarum), Tiao Qin (Scutellariae Radix), Dou Gen (Phaseoli Caulis), and Gua Lou Ren. Do not use Bai Zhu (Atractylodis Macrocephalae Rhizoma) or Mu Xiang (Vladimiriae Radix) to strengthen the Spleen. If the discharged material smells like rotten eggs, it indicates food stagnation. Use Shan Zha (Crataegi Fructus), Mai Ya (Hordei Fructus Germinatus), Bing Lang (Arecae Semen), and Chuan Po (Magnoliae Officinalis Cortex) to resolve food accumulation.
The Classic states: "In diarrhea, pathogens enter the Large Intestine and exit as they entered because pathogenic heat fails to transform grain." This occurs because the nature of Fire is boiling and turbulent, leaving no time for separation and digestion, resulting in direct expulsion. When diarrhea is severe, all cold and cooling resolving medicines are contraindicated. However, this does not apply generally to treating dysentery caused by Heat Toxin. If Heat Toxin is too severe, it cannot fully vent onto the skin surface; instead, it tends to cause congestion, slippage, and stagnation. Fortunately, if the interior is solid and resists pathogens, the toxin invades and pours into the Large Intestine. The Large Intestine is the official of transmission; unless the toxin forces its way through causing frequent dysentery, which resembles diarrhea but is fundamentally different. Dysentery presents with slippery incontinence, whereas diarrhea presents with hardness and blockage; dysentery involves loose, unformed stools, while diarrhea involves coagulation like glue or lacquer. Some cases involve pure watery discharge, some have little foul odor, some involve fecal impaction difficult to pass, and some feature abdominal pain and irritability. In these cases, heavily use Qin (Scutellariae Radix) and Lian (Coptidis Rhizoma) to clear Fire, and slightly add Da Huang to attack the toxin, so dysentery will cease. Treating this as simple diarrhea would be a grave error. The Classic states: "Heat Toxin rushing to the intestines causes frequent bowel movements; the intestines transmit toxins making invasion difficult. Frequent urges remain hard to control; mistaking it for Spleen Deficiency leads to internal attack." In chronic diarrhea, food stagnates in the middle, obstructing Middle Qi, failing in transportation duties, and exhausting the Spleen. Even in favorable cases, recovery is delayed. For internal injury, resolve accumulation and stop diarrhea/vomiting; after heat subsides and stool becomes blocked, add Sheng Ma to lift Qi, ensuring both upper and lower passages become smooth.