《金匮》曰∶妇人伤寒发热，经水适来，昼日明了，暮则谵语，如见鬼状，此为热入血室，治之无犯胃气及上二
焦必自愈也。此言发热病之初也。经水适来，邪盛而经气亦盛，寒邪伤荣，故邪与血搏，血属阴主夜，故昼则虽热
而明了，暮则入阴分，邪挟阴气而为谵语，如见鬼状者，谵之甚也。此为热入血室。然血室虽在内，而表邪实未尝犯
胃及上二焦，故治法亦惟和表邪，兼清血室之热足矣。误以为客邪入内攻之，则伐及无辜，导邪入内矣。故曰无犯胃气，
及上二焦，必自愈也。然冲为血海，即是血室，冲脉得热则逼血下行，男子亦有之，不独妇人也。
《金匮》曰∶病有血分、水分，何也？经水前断，后病水，名曰血分，此病为难治。先病水，后断经，名曰水分，
此病易治。盖去水，后断经，名曰水分，此病易治。盖去水，其经自下也。《圣济》曰∶血分者，经水通之际，因寒热
伤其冲任，气壅不行，播在皮肤，邪气相搏，经血分而为水，发为浮肿，故曰血分，久不治积成水肿，即难治。水
分者，以水气上溢皮肤，散于四肢，发为浮肿，盖肾者，胃之关，关门不利，故聚水而从其类，病水而经乃断矣。《证治》
又曰∶经事不通，血入四肢，化为水，遂成肿满，非独产后为然，名曰血分，误作水治，其害不小，宜调经散，盖气者，
水之母，血者，气所化，非气无法以生血，非血无以养气。若经水不通，则血病气亦病，岂有水不通而能化血乎？
血不通而化水者，乃是气壅不能化血而成水也，观桃仁丸可见矣。
《金匮要略》说：妇女患伤寒发热，月经正好来潮，白天神志清醒，到了晚上却胡言乱语，好像看见了鬼怪一样，这是热邪陷入血室（子宫及冲脉），治疗时不要损伤胃气以及上焦、中焦，病一定会自行痊愈。这里说的是发热病的初期阶段。月经正当来潮时，邪气盛而经气也盛，寒邪损伤营血，所以邪气与血液搏结。血属阴主夜间，所以白天虽然发热但神志清楚，到了晚上邪气进入阴分，邪气挟带阴气导致胡言乱语，像看见鬼怪一样，这是谵语严重的表现。这就是热入血室。然而血室虽然在体内，但表邪实际上并没有侵犯胃和上、中二焦，所以治疗方法也只是调和表邪，兼清血室之热就够了。如果错误地认为客邪进入体内而进行攻伐，就会伤害无辜的正气，反而引导邪气深入体内。所以说不要损伤胃气及上、中二焦，病一定会自行痊愈。然而冲脉是血海，也就是血室，冲脉受热则逼迫血液下行，男子也有这种情况，并不只限于妇女。
《金匮要略》说：疾病有血分和水分之分，这是什么意思呢？月经先停止，后来发生水肿，叫做血分，这种病难治。先发生水肿，后来月经停止，叫做水分，这种病容易治疗。因为去除水湿后，月经自然会通畅。《圣济总录》说：血分证，是在月经通调之际，因寒热邪气损伤冲任二脉，气机壅滞不通，流注于皮肤，邪气相互搏结，经血分离而化为水，发为浮肿，所以叫血分，如果久治不愈积聚起来成为水肿，就难以治疗。水分证，是因为水气上溢至皮肤，散布于四肢，发为浮肿。肾是胃的关口，如果关门不利，就会导致水液聚集并同类相从，先患水病而后月经断绝。《证治准绳》又说：月经不通，血液流入四肢，化为水，遂成肿胀满闷，这不仅仅发生在产后，称为血分，如果错误地当作水病治疗，危害不小，适宜使用调经散。因为气是水之母，血是由气化生的，没有气就无法生成血，没有血就无法滋养气。如果月经不通，那么血病气也会病，哪里有水不通却能化生血的道理呢？血不通而化为水，乃是气机壅滞不能化血而成水所致，观察桃仁丸的方义就可以明白了。
The *Jingui Yaolue* states: When a woman suffers from Shanghan (Cold Damage) with fever, and her menses happen to arrive, she is lucid during the day but becomes delirious at night, seeing visions as if of ghosts. This is termed "Heat Entering the Blood Chamber" (Re Ru Xue Shi). Treatment should not injure the Stomach Qi or the Upper and Middle Jiao; the condition will heal itself. This refers to the initial stage of the febrile disease. When menses are arriving, both the pathogenic factor and the meridian Qi are abundant. Cold pathogen damages Ying (Nutritive) blood, so the pathogen contends with the blood. Since blood belongs to Yin and governs the night, although there is fever during the day, consciousness remains clear. At night, the pathogen enters the Yin aspect; contending with Yin Qi, it causes severe delirium, manifesting as seeing ghosts. This constitutes Heat Entering the Blood Chamber. Although the Blood Chamber is located internally, the exterior pathogen has not actually invaded the Stomach or the Upper and Middle Jiao. Therefore, the treatment method only requires harmonizing the exterior pathogen and clearing the heat in the Blood Chamber. Mistakenly treating it as an internal invader and using purgative methods would harm healthy tissue and guide the pathogen inward. Hence, it is said that by not injuring the Stomach Qi and the Upper and Middle Jiao, the disease will resolve spontaneously. However, the Chong Mai (Penetrating Vessel) is the Sea of Blood, which is also the Blood Chamber. When the Chong Mai receives heat, it forces blood downward; this can occur in men as well, not just women.
The *Jingui Yaolue* asks: What distinguishes Blood Division (Xue Fen) and Water Division (Shui Fen)? If menstruation stops first, followed by edema, it is called Blood Division, which is difficult to treat. If edema occurs first, followed by the cessation of menstruation, it is called Water Division, which is easy to treat. This is because once the water retention is resolved, menstruation will naturally resume. The *Shengji Zonglu* states: In Blood Division, at the time when menstruation is regular, cold or heat pathogens damage the Chong and Ren vessels. Qi becomes stagnant and fails to circulate, spreading into the skin. Pathogenic factors contend with each other, causing menstrual blood to separate and transform into water, resulting in edema. Thus, it is named Blood Division. If left untreated for a long time, it accumulates into generalized edema, becoming difficult to treat. In Water Division, water qi overflows onto the skin and disperses into the four limbs, causing edema. The Kidney is the gate of the Stomach; if the gate is dysfunctional, water gathers according to its nature. One contracts water disease first, and then menstruation ceases. The *Zhengzhi Zhunsheng* further states: When menstruation is obstructed, blood enters the four limbs and transforms into water, leading to swelling and fullness. This is not exclusive to postpartum conditions and is named Blood Division. Mistaking it for water disease and treating it accordingly causes significant harm; Tiaojing San (Regulate Menses Powder) is appropriate. Qi is the mother of water, and blood is transformed from Qi. Without Qi, blood cannot be generated; without blood, Qi cannot be nourished. If menstruation is blocked, blood pathology leads to Qi pathology. How can water obstruction exist while blood transformation continues? Blood failing to flow and transforming into water is due to Qi stagnation preventing the transformation of blood into water. This can be understood by observing the formula Tao Ren Wan (Peach Kernel Pill).