此治小便不利之主方，乃治三焦水道，而非太阳药也。《素问·经脉别论》曰∶“饮入于胃，游溢精气，上输于脾，
脾气散精，上归于肺，通调水道，下输膀胱，水精四布，五经并行。”此方用桂以助命门之火，是釜底加薪，而后胃中之
精气上腾；再用白术健脾，以转输于肺；而后用二苓泽泻，运水道之升已而降。其先升后降之法，与《内经》之旨，滴
滴归源，复与太阳何涉？《伤寒论》治小便不利，“汗出而渴者，五苓散主之，不渴者，茯苓甘草汤主之。”盖渴为阳气
不足，水不上升也，不升则不降，故用肉桂以升之，二苓、泽泻以降之，而用白术一味，以为中枢。乃注者莫不以渴为
热入膀胱，津液被劫所致，如果热入，而复用桂、术，以温液耗津，又二苓、泽泻以渗之，是热之又热，耗之又耗，速
之毙矣。且不渴者，反不用五苓，而用茯苓甘草汤，可知不渴则无需桂、术之蒸腾津液，而桂、术之非治太阳，而治三
焦，更不待言矣。有小便不通而以桂枝易桂者，此必命门之火未衰，而外有太阳表症，因邪伤太阳，传入三焦，故表邪
未解，而三焦之水道不利，即《伤寒论》所谓“中风发热，六七日不解而烦，有表里证，渴欲饮水，水入则吐者，名曰
水逆，五苓散主之”是也。表症为太阳不足，故用桂枝以宣阳气，通津液于周身，即《经》文“水精四布，五经并行”
之旨，非用之以通水道下出也。里症为三焦之气化不宣，故用二苓之泻，以通三焦之闭塞，非开膀胱之溺窍也。夫下焦
之气化不宣，则腹膨而小便不利，水蓄膀胱，此乃水蓄于膀胱之外，不能化入膀胱，故用五苓以化之。亦有用桂枝而效
者，因卫出下焦，助太阳气化以运之，非为太阳腑内之水蓄也。如三焦既将水气运化入于膀胱而不出，此真太阳府内痹
而不宣，即胞痹症也。《素问·痹论》曰∶“胞痹者，少腹膀胱按之内痛，若沃以汤，涩于小便，上为清涕。”水在膀胱之
内，是膀胱胀满而非腹胀，故按之内痛；若沃以汤，其溺孔之道痹而不通，故涩于小便；膀胱痹气随太阳经脉之行以从
巅入脑，故上为清涕。此真太阳本府水结膀胱之内，而非腹中膨胀之小便不利也。总之、水入膀胱之内，方属太阳，若
水在膀胱之外，腹膨满而小水不利者，此脏腑之外，躯壳之内，三焦主之。虞大民曰∶三焦者，指腔子而言也。故治腹
满肿胀之症，设使一味利水，则三焦之气更不能施化，而膀胱津液为之下竭，非仲景五苓之意也。
这是治疗小便不利的代表方剂，它是针对三焦水道进行调理的，而不是治疗太阳经病的药物。《素问·经脉别论》中说：“饮水进入胃中，精气游溢散布，向上输送到脾；脾气散精，向上归于肺；肺通调水道，向下输送到膀胱；水液精华四布全身，五脏经脉并行运行。”此方用桂枝来助长命门之火，如同在锅底下添加柴火，从而使胃中的精气向上蒸腾；再用白术健脾，以转输精气于肺；然后用茯苓、猪苓和泽泻，使水道之气先升后降。这种先升后降的方法，与《内经》的宗旨完全契合，滴水归源，又与太阳经有什么关系呢？《伤寒论》治疗小便不利时说：“出汗且口渴的，用五苓散主治；不口渴的，用茯苓甘草汤主治。”大概口渴是因为阳气不足，水液不能上升；不升则无法下降，所以用肉桂来升提阳气，用茯苓、猪苓和泽泻来引导下行，并用白术一味药作为中枢枢纽。然而注释者没有不把口渴归结为热邪侵入膀胱，导致津液被劫夺所致。如果真是热邪侵入，反而使用桂枝、白术来温煦，这会耗伤津液，再加上茯苓、泽泻的渗利作用，这是热上加热，耗上加耗，会加速病人的死亡。而且不口渴的病人，反而不用五苓散，而用茯苓甘草汤，由此可知，不口渴就不需要桂枝、白术来蒸腾津液，从而更证明了桂枝、白术不是治疗太阳经病，而是治疗三焦病，这就不言自明了。有人用小便不通时，用桂枝代替肉桂，这一定是因为命门之火并未衰弱，而体表有太阳表证，因邪气伤害太阳经，传入三焦，所以表邪未解，同时三焦的水道也不通畅，这就是《伤寒论》所说的“中风发热，六七天未解且心烦，有表里证，想喝水，水喝下去就吐的，名叫水逆，用五苓散主治”的情况。表证是因为太阳阳气不足，所以用桂枝来宣发阳气，使津液通达周身，即《内经》文中“水液精华四布，五脏经脉并行”的宗旨，并不是用它来通导水道从下排出。里证是因为三焦的气化功能不宣通，所以用茯苓、猪苓的渗泄作用，来通利三焦的闭塞，并不是开通膀胱的排尿窍道。如果下焦的气化功能不宣通，就会出现腹部膨隆和小便不利，水蓄积在膀胱之外，这是因为水蓄积在膀胱外面，不能化入膀胱内部，所以用五苓散来化解它。也有使用桂枝而有效的，这是因为卫气出于下焦，辅助太阳气化来运化水湿，并不是为了治疗太阳腑内蓄积的水饮。如果三焦已经将水气运化进入膀胱但排不出来，这才是真正的太阳腑内痹阻而不宣通，也就是胞痹症。《素问·痹论》说：“胞痹，表现为少腹膀胱部位按压时内部疼痛，像浇了热水一样灼热，小便涩滞不畅，上部出现清涕。”水在膀胱内部，是膀胱胀满而不是腹部膨胀，所以按压时内部疼痛；像浇了热水一样，其尿道通道痹阻不通，所以小便涩滞；膀胱的痹阻之气随着太阳经脉的运行从头顶进入脑部，所以上部出现清涕。这才是真正的太阳本腑水结在膀胱内部，而不是腹部膨胀的小便不利。总之，水进入膀胱内部，才属于太阳经病范畴；如果水在膀胱外部，腹部膨满而小便不利，这是脏腑之外、躯壳之内，由三焦主管。虞大民说：三焦，指的是体腔而言。所以治疗腹部胀满肿胀的病证，如果使用一味利水的药物，那么三焦的气机更不能施化，而膀胱的津液也会因此在下枯竭，这就不是仲景五苓散的意旨了。
This is the principal formula for treating difficulty in urination; it regulates the water passages of the Sanjiao (Triple Burner), rather than being a medicine for the Taiyang (Greater Yang) channel. The *Suwen: Jingmai Bie Lun* states: "When drink enters the stomach, its essence floats and overflows, moving upward to be transported by the Spleen; the Spleen scatters the essence, sending it upward to return to the Lung; the Lung regulates and smooths the water passages, transmitting them downward to the Bladder; the water essence distributes throughout the four directions, and the five meridians run in parallel." This formula uses Cinnamon Twig (*Guizhi*) to assist the fire of the Mingmen (Gate of Life), akin to adding fuel to the bottom of a pot, thereby causing the essence and qi of the Stomach to ascend; then using Atractodis Rhizoma (*Baizhu*) to strengthen the Spleen and transport essence to the Lung; subsequently employing Poria (*Fuling*), Polyporus (*Zeling*), and Alisma Rhizome (*Zexie*) to facilitate the ascending and then descending movement of the water passages. This method of first ascending and then descending aligns perfectly with the principles of the *Neijing*, returning every drop to its source, and has no relation to the Taiyang channel. In the *Shanghan Lun*, regarding difficulty in urination: "If there is sweating and thirst, Wuling San (Five-Ingredient Powder with Poria) should govern it; if there is no thirst, Lingcao Ganjiang Tang (Poria, Licorice, and Dried Ginger Decoction) should govern it." Generally, thirst indicates insufficient Yang Qi, preventing water from ascending; without ascending, there can be no descending. Therefore, Cinnamon Twig (*Guizhi*) is used to raise it, while Poria (*Fuling*), Polyporus (*Zeling*), and Alisma Rhizome (*Zexie*) are used to lower it, with Atractodis Rhizoma (*Baizhu*) serving as the central pivot. However, commentators have universally attributed thirst to heat entering the Bladder, causing fluid depletion. If heat had truly entered, using Cinnamon Twig (*Guizhi*) and Atractodis Rhizoma (*Baizhu*) to warm would consume fluids, and combined with the draining action of Poria (*Fuling*) and Alisma Rhizome (*Zexie*), this would be heat upon heat and consumption upon consumption, hastening death. Moreover, those without thirst do not use Wuling San but instead use Lingcao Ganjiang Tang. This shows that without thirst, there is no need for Cinnamon Twig (*Guizhi*) and Atractodis Rhizoma (*Baizhu*) to vaporize fluids, further proving that these herbs treat the Sanjiao rather than the Taiyang, which goes without saying. In cases of urinary obstruction where Cinnamon Twig (*Guizhi*) is substituted for Cinnamon Bark (*Rougui*), it is likely because the fire of the Mingmen (Gate of Life) is not deficient, but there is an exterior Taiyang syndrome. Because pathogenic factors injured the Taiyang channel and transmitted to the Sanjiao, the exterior pathogen remains unresolved while the water passages of the Sanjiao are obstructed. This corresponds to what the *Shanghan Lun* calls: "Wind-strike with fever, unresolved after six or seven days, accompanied by irritability, presenting both exterior and interior syndromes, thirst with desire to drink, but vomiting immediately after drinking, named Shuini (Water Reversal), governed by Wuling San (Five-Ingredient Powder with Poria)." The exterior syndrome stems from Taiyang deficiency, so Cinnamon Twig (*Guizhi*) is used to disseminate Yang Qi and circulate fluids throughout the body, adhering to the principle in the classics: "Water essence distributes throughout the four directions, and the five meridians run in parallel," not to promote urination downward. The interior syndrome results from the failure of Sanjiao Qi transformation to unblock, so the draining actions of Poria (*Fuling*) and Polyporus (*Zeling*) are used to open Sanjiao blockage, not to open the urethral orifice of the Bladder. When Qi transformation in the Lower Jiao fails to unblock, abdominal distension and difficulty in urination occur; water accumulates outside the Bladder because it cannot transform into the Bladder. Thus, Wuling San (Five-Ingredient Powder with Poria) is used to resolve it. There are also cases where Cinnamon Twig (*Guizhi*) is effective because Wei Qi (Defensive Qi) originates from the Lower Jiao, assisting Taiyang Qi transformation to move water, not to treat water accumulation within the Taiyang Fu organ. If the Sanjiao has transported water qi into the Bladder but it cannot exit, this is true Bi (Obstruction) within the Taiyang Fu organ, known as Baobi (Bladder Bi). The *Suwen: Bilun* states: "Baobi presents as internal pain upon pressing the lower abdomen and Bladder area, feeling as if soaked in hot water, with difficult and scanty urination, and clear nasal discharge above." Water inside the Bladder causes Bladder fullness rather than abdominal distension, hence internal pain upon pressing; feeling as if soaked in hot water indicates the urinary passage is blocked and unpatent, leading to difficult urination; the Bi Qi of the Bladder follows the Taiyang meridian pathway from the vertex into the brain, causing clear nasal discharge above. This is true water binding within the Taiyang Fu organ, distinct from urinary difficulty accompanied by abdominal distension. In summary, only when water enters the interior of the Bladder does it belong to the Taiyang category; if water is outside the Bladder, causing abdominal distension and difficult urination, this is governed by the Sanjiao, located outside the Zang-Fu organs and within the body shell. Yu Damin stated: The Sanjiao refers to the body cavity. Therefore, in treating abdominal fullness and swelling, if one uses only diuretic herbs, the Qi of the Sanjiao will fail to transform and distribute, and the fluids of the Bladder will be exhausted below. This contradicts the intent of Zhongjing's Wuling San (Five-Ingredient Powder with Poria).