治皮水四肢肿。水气在皮肤中。四肢聂聂动者。此汤主之。
防己 黄 桂枝（各三两。） 茯苓（六两。） 甘草（二两。）
上五味。以水六升。煮取二升。分温三服。
歌曰 四肢聂聂动无休。皮水情形以此求。己桂 三草二两。茯苓六两砥中流。
徐忠可云。药亦同防己黄 汤。但去术加桂苓者。风水之湿在经络。近内。皮水之湿在
皮肤。近
之营卫。
（见上。） 里水病。此汤主之。甘草麻黄汤亦主之。
男元犀按。风水皮水之外。有正水而兼色黄。名里水。里水虽无发汗之法。而邪盛正不
衰者
如
甘草（二两。） 麻黄（四两。）
上二味。水五升。先煮麻黄。去上沫。内甘草。煮取三升。温服一升。重覆汗出。不汗
再服
歌曰 里水原来自内生。一身面目肿黄呈。甘须二两麻黄四。气到（二药上宣肺气。中
助土
蔚按。麻黄发汗最捷。徐灵胎谓其无气无味。不专一经。而实无经不到。盖以出入于空
虚之
（即麻黄附子甘草汤。歌见长沙方歌括。）
麻黄 附子 甘草
杏子汤（阙。徐、尤云。疑是麻杏甘石汤。） 水之为病。其脉沉小。属少阴。浮者为
风。无水虚胀者为气水。发其汗即已。脉沉者。宜麻黄附子汤。浮者。宜杏子汤。
客问曰。金匮水气篇。杏子汤方阙。诸家注说。疑为麻杏甘石汤。不知是否。犀答曰。
非也。麻杏甘石汤。伤寒论治发汗后汗出而喘。主阳盛于内也。本节云。水之为病发其汗即
已。未云热之为病自汗出也。盖麻杏甘石汤治内蕴化热自汗出之症。此水之为病发其汗为宜。
则
病
胃
然则此篇师言脉沉小属少阴。用附子温经散寒。主石水之病。即可知脉浮属太阳。用杏子启
太阴之气。主正水之病。为变其脉症言之也。恐石膏之凝寒。大有关于脾肾。故不可用焉。
高明如徐忠可及二张二程。俱疑为麻杏甘石汤。甚矣。读书之难也。而余以为其即麻黄、杏
仁、甘草三味。不知是否。以俟后之学人。客悦而去。
治疗皮水证，表现为四肢浮肿。这是由于水气停留在皮肤之中，导致四肢出现轻微颤动的症状。此方主治此类病症。
以上五味药，用水六升，煎煮至剩余二升药液，分三次温服。
歌诀曰：四肢轻微颤动无休止，皮水的病机以此推求。防己、桂枝各三两，甘草二两，茯苓六两如中流砥柱般稳固中焦。
徐忠可评论说：药物组成与防己黄芪汤相同，只是去掉了白术，加入了桂枝和茯苓。这是因为风水证的湿邪在经络，位置较深；而皮水证的湿邪在皮肤，接近营卫之气。
男元犀按语：在风水、皮水之外，还有正水兼见面色发黄的情况，称为里水。里水虽然通常没有发汗的治疗方法，但对于邪气盛而正气不衰的患者，可以使用发汗法。
以上两味药，用水五升，先煎煮麻黄，去掉浮沫，再加入甘草，煎煮至剩余三升药液，温服一升。服药后覆盖衣被以助出汗，若未出汗，再服用一次。
歌诀曰：里水原本由内生，全身面目肿胀且发黄。甘草需二两，麻黄用四两，宣通上焦肺气，辅助中焦脾土运化。
蔚按语：麻黄发汗作用最为迅速。徐灵胎认为它无气无味，不专入一经，但实际上无处不到。盖因其出入于空虚之处……
（即麻黄附子甘草汤，歌诀见《长沙方歌括》。）
杏子汤（缺方。徐灵胎、尤在泾认为，怀疑是麻杏甘石汤。）水气为病，脉象沉小，属于少阴经；脉象浮的属于风邪所致；无水而虚胀的是气水，发汗即可治愈。脉沉的，适宜用麻黄附子汤；脉浮的，适宜用杏子汤。
客人问道：《金匮要略·水气篇》中，杏子汤的方剂缺失。各家注解都怀疑它是麻杏甘石汤，不知是否正确？我回答：不对。麻杏甘石汤出自《伤寒论》，治疗发汗后汗出而喘的症状，主治阳热盛于体内。本节经文说：“水气为病，发其汗即已”，并没有说是热病导致自汗。麻杏甘石汤治疗的是内蕴化热、自汗出的病症；而这里是水气为病，适宜发汗，所以不能用麻杏甘石汤。
既然这样，那么本篇中老师说“脉沉小属少阴”，使用附子温经散寒，主治石水病；就可以推知“脉浮属太阳”，使用杏子汤启太阴之气，主治正水病。这是从脉症变化的角度而言的。恐怕石膏性味凝寒，对脾肾大有影响，所以不可使用。
高明如徐忠可及张景岳、程国彭等医家，都怀疑是麻杏甘石汤，可见读书之难啊。而我认为是由麻黄、杏仁、甘草三味药组成，不知是否准确，留待后世学者考证。客人听后心悦诚服地离去。
Treats Pi Shui (Skin Water Edema), characterized by edema of the four limbs. This is due to water qi stagnating within the skin, causing slight tremors in the four limbs. This decoction is indicated for such conditions.
Fangji (Stephaniae Tetrandrae Radix), Huangqi (Astragali Radix), Guizhi (Cinnamomi Ramulus) (each 3 liang). Fuling (Poria) (6 liang). Gancao (Glycyrrhizae Radix et Rhizoma) (2 liang).
Take the above five herbs. Add 6 sheng of water, boil to obtain 2 sheng of liquid, and divide into three warm doses.
Song says: Slight tremors in the four limbs cease not; the condition of Pi Shui is sought through this formula. Fangji and Guizhi each 3 liang, Gancao 2 liang, Fuling 6 liang acts as a pillar in the middle flow.
Xu Zhongke commented: The ingredients are the same as Fangji Huangqi Tang, but Baizhu (Atractylodis Macrocephalae Rhizoma) is removed and Guizhi (Cinnamon Twig) and Fuling (Poria) are added. This is because the dampness in Feng Shui (Wind Water) resides in the meridians and is closer to the interior, whereas the dampness in Pi Shui (Skin Water) resides in the skin and is closer to Ying Wei (Nutritive and Defensive Qi).
(See above.) For Li Shui (Interior Water disease), this decoction is indicated. Gancao Mahuang Tang (Licorice and Ephedra Decoction) is also indicated.
Nan Yuanxi noted: Besides Feng Shui (Wind Water) and Pi Shui (Skin Water), there is Zheng Shui (True Water) accompanied by yellow complexion, named Li Shui (Interior Water). Although Li Shui generally does not employ sweating methods, for patients with excess pathogen and non-depleted righteous qi, sweating methods can be used.
Gancao (Licorice Root) (2 liang). Mahuang (Ephedrae Herba) (4 liang).
Take the above two herbs. Add 5 sheng of water. First boil Mahuang (Ephedra), remove the foam on the surface, then add Gancao (Licorice Root). Boil to obtain 3 sheng of liquid. Take 1 sheng warm. Cover with blankets to induce sweating. If no sweat occurs, take another dose.
Song says: Li Shui (Interior Water) originates from within; the whole body and face appear swollen and yellow. Gancao (Licorice Root) must be 2 liang, Mahuang (Ephedra) 4 liang. It promotes the dispersing of Lung Qi upwards and assists the transformation of Earth Qi in the middle.
Wei noted: Mahuang (Ephedra) induces sweating most swiftly. Xu Lingtai stated that it has no specific flavor or odor and does not belong exclusively to one meridian, yet in reality, it reaches every meridian. This is because it enters and exits through empty spaces...
(i.e., Mahuang Fuzi Gancao Tang (Ephedra, Aconite, and Licorice Decoction); the song is found in Changsha Fang Ge Kuo.)
Mahuang (Ephedrae Herba), Fuzi (Aconiti Lateralis Radix Praeparata), Gancao (Glycyrrhizae Radix et Rhizoma).
Xingzi Tang (Apricot Kernel Decoction) (Formula missing. Xu [Lingtai] and You [Zaijing] suspected it was Maxing Shigan Tang (Ephedra, Apricot Kernel, Glycyrrhiza, and Gypsum Decoction)). In diseases of water, if the pulse is deep and small, it belongs to Shaoyin (Lesser Yin); if floating, it belongs to Wind. Empty distension without water accumulation is Qi Water (Qi Distension). Inducing sweating will cure it. If the pulse is deep, Mahuang Fuzi Tang (Ephedra and Aconite Decoction) is suitable. If floating, Xingzi Tang (Apricot Kernel Decoction) is suitable.
The guest asked: In the "Water Qi Chapter" of Jin Gui Yao Lue, the formula for Xingzi Tang (Apricot Kernel Decoction) is missing. Various commentators suspect it is Maxing Shigan Tang (Ephedra, Apricot Kernel, Glycyrrhiza, and Gypsum Decoction). Is this correct? I answered: No. Maxing Shigan Tang (Ephedra, Apricot Kernel, Glycyrrhiza, and Gypsum Decoction) appears in Shang Han Lun (Treatise on Cold Damage) to treat panting with sweating after improper sweating therapy, indicating excessive Yang heat internally. The text here states: "In diseases of water, inducing sweating cures it," and does not mention spontaneous sweating due to heat. Maxing Shigan Tang (Ephedra, Apricot Kernel, Glycyrrhiza, and Gypsum Decoction) treats symptoms of internal heat accumulation with spontaneous sweating. Here, the pathology is water disease, where inducing sweating is appropriate. Therefore, Maxing Shigan Tang (Ephedra, Apricot Kernel, Glycyrrhiza, and Gypsum Decoction) should not be used.
Since then, regarding the Master's statement that "deep and small pulse belongs to Shaoyin," using Fuzi (Prepared Aconite Root) to warm the meridians and dispel cold indicates treatment for Shi Shui (Stone Water). From this, we can infer that "floating pulse belongs to Taiyang" (Greater Yang), using Xingzi Tang (Apricot Kernel Decoction) to activate Taiyin (Greater Yin) Qi, indicating treatment for Zheng Shui (True Water). This discusses the variation in pulse and symptoms. One might fear that the cold-coagulating nature of Shigao (Gypsum Fibrosum) would significantly affect the Spleen and Kidney, hence it cannot be used.
Scholars as eminent as Xu Zhongke, Zhang Jingyue, and Cheng Guopeng all suspected it was Maxing Shigan Tang (Ephedra, Apricot Kernel, Glycyrrhiza, and Gypsum Decoction). Indeed, reading classics is difficult. I believe it consists of Mahuang (Ephedrae Herba), Xingren (Armeniacae Semen Amarum), and Gancao (Glycyrrhizae Radix et Rhizoma). Whether this is correct remains to be verified by future scholars. The guest left pleased.