昌黎谓软脚病。江南之人。常常见之。则西北希有。盖东方滨海傍水。鱼盐
之地。其民食鱼嗜咸。令人热中。南方地下。水土弱。雾露所聚。其民嗜酸食
。病则挛痹。此则湿与热合而成病也。然湿者类水。喜就下。而热往从之。
注于足胫。则赤肿而疼。乃妨步履。甚则逆而上攻。呕恶不食。作寒热而似
外感。俗谓之香港脚伤寒。大可嗤也。夫寒伤经络。从足走头。故头疼恶寒而
名伤寒。湿从下受。害皮肉筋骨。故红肿疼重而成香港脚。一天一渊。如风马
牛之不相及也。然有从内而感。则酒湿乳酪之所致。从外而入。则风雨雾
露之所侵。不从内不从外而得。则肥壮人气之所及。或湿痰下注。或阴火
下流。种种不一。而要以祛湿热为主。养血凉血次之。舒筋除燥次之。使不
辨其方宜。不别其居处。不观其勇怯。不调其气血。而概以二妙投之。恐不
克副其名也。将若何。
苍术除湿汤
茅山苍术（一钱泔制） 黄柏（七分酒炒） 生地（一钱） 宣木瓜（一钱） 米仁（二钱） 牛膝（一钱） 当
归（一钱） 独活（七分） 广皮（八分） 茯苓（一钱）
灯芯一握。生姜一片。水煎。饮酒人。加葛根泽泻各一钱。或加汉防己。
白术汤 治气血亏损。足胫疼痛。
白术（一钱土炒） 人参（一钱） 茯苓（一钱） 牛膝（一钱）
黄柏（一钱） 苍术（七分泔制） 当归（一钱） 白芍药（一钱酒炒） 木瓜（一钱） 柴胡（五分） 广皮（一钱）
枣二枚。姜一片。水煎。
丹溪妇人足胫痛。用
红花 牛膝（俱酒洗） 生地 黄柏 苍术 南星 龙胆草 川芎
水煎服。
又治脚软筋痛。用
牛膝（二两） 白芍药（一两半） 龟板（酒炙） 柏板（酒炒各一两） 知母（炒） 甘草（各五钱）
为末。酒糊丸。
二妙丸
苍术（二两米泔浸炒） 黄柏（二两酒炒）
为末。神曲糊丸。
换腿丸 治足三阴经为风寒暑湿之气所乘。发为挛痹缓纵。或上攻胸
背。下注脚膝。疼痛发热。行步艰辛。
薏苡仁 南星 石楠叶 石斛 槟榔 萆 （酒拌） 牛膝（酒浸） 羌活 防风 木瓜（各四两）
黄（蜜炙） 当归（酒拌） 明天麻 续断（酒炒各一两）
右为末。酒糊丸。如桐子大。每服五十丸。盐汤下。
昌黎先生曾说“软脚病”。在江南地区，人们经常见到这种病症，而在西北地区则很少见。这是因为东方靠近海边和水域，是盛产鱼盐的地方，当地百姓多吃鱼且口味偏咸，容易导致体内积热；南方地势低洼，水土之气薄弱，雾气露水聚集，当地百姓喜好酸味食物，患病后容易出现肢体拘挛和痹痛。这主要是由于湿邪与热邪结合而形成的疾病。然而，湿性类水，喜欢向下流动，而热邪会随之向下走注于足胫部，导致局部红肿疼痛，进而妨碍行走。严重时，病气会逆向上攻，出现呕吐、恶心、不能进食，并伴有寒热交替的症状，看起来像外感风寒。世俗称之为“香港脚伤寒”，这是非常荒谬的。
寒邪损伤经络，是从足部向头部传变的，所以会出现头痛、恶寒等症状，因此称为“伤寒”；湿邪从下部受侵，伤害皮肉筋骨，所以出现红肿、疼痛、沉重等症状，从而形成“香港脚”。两者截然不同，就像风马牛不相及一样。但是，也有从内部感受病因的，这是由于饮酒过多以及食用乳酪等所致；从外部侵入的，则是风雨雾露等外邪所侵袭；既不从内也不从外获得的，则是由于身体肥胖壮实之人气血壅滞所致。或者是湿痰下注，或者是阴火下流，情况多种多样，但治疗总要以祛除湿热为主，养血凉血次之，舒筋除燥再次之。如果不辨别治疗的适宜方法，不区分居住环境，不观察患者的体质强弱，不调理其气血，而一概使用二妙散投治，恐怕难以符合该方的名实相符。那么应该怎么办呢？
苍术除湿汤：
茅山苍术（一钱，用淘米水炮制） 黄柏（七分，用酒炒） 生地（一钱） 宣木瓜（一钱） 薏苡仁（二钱） 牛膝（一钱） 当归（一钱） 独活（七分） 广陈皮（八分） 茯苓（一钱）
灯芯草一握，生姜一片，加水煎煮。饮酒者，加葛根、泽泻各一钱，或者加汉防己。
白术汤：治疗气血亏损引起的足胫疼痛。
白术（一钱，用土炒） 人参（一钱） 茯苓（一钱） 牛膝（一钱）
黄柏（一钱） 苍术（七分，用淘米水炮制） 当归（一钱） 白芍药（一钱，用酒炒） 木瓜（一钱） 柴胡（五分） 广陈皮（一钱）
大枣两枚，生姜一片，加水煎煮。
丹溪治疗妇人足胫疼痛，使用：
红花 牛膝（均用酒洗） 生地 黄柏 苍术 南星 龙胆草 川芎
加水煎煮服用。
又治疗脚软筋痛，使用：
牛膝（二两） 白芍药（一两半） 龟板（酒炙） 柏子仁板（酒炒，各一两） 知母（炒） 甘草（各五钱）
研为细末，用酒糊制作成丸剂。
二妙丸：
苍术（二两，用米泔水浸泡后炒） 黄柏（二两，用酒炒）
研为细末，用神曲糊制作成丸剂。
换腿丸：治疗足三阴经受到风寒暑湿邪气侵袭，引发肢体拘挛、痹痛、弛缓无力，或者病气上攻胸背，下注脚膝，出现疼痛发热，行走艰难。
薏苡仁 南星 石楠叶 石斛 槟榔 萆薢（酒拌） 牛膝（酒浸） 羌活 防风 木瓜（各四两）
黄芪（蜜炙） 当归（酒拌） 明天麻 续断（酒炒，各一两）
以上药物研为细末，用酒糊制作成丸剂，大小如梧桐子。每次服用五十丸，用盐汤送服。
Changli stated that "soft foot disease" is commonly seen in the Jiangnan region but rarely found in the northwest. This is because the eastern regions are near the sea and water bodies, areas rich in fish and salt. The local people consume a lot of fish and prefer salty food, which can cause heat to accumulate internally. In the south, the terrain is low-lying, the soil and water qi are weak, and fog and dew gather there. The locals favor sour foods, and when ill, they often suffer from limb contracture and bi-syndrome (painful obstruction). This condition arises from the combination of dampness and heat. Dampness, resembling water, tends to flow downward, and heat follows it, pouring into the shins and feet, causing redness, swelling, and pain, thereby hindering walking. In severe cases, the pathogenic factor may counter-flow upward, causing vomiting, nausea, loss of appetite, and alternating chills and fever, resembling an external contraction. It is vulgarly called "Hong Kong Foot Cold Damage," which is absurd.
Cold damage affects the meridians, traveling from the feet to the head; thus, it presents with headache and aversion to cold, hence named "Cold Damage." Dampness is contracted from below, damaging the skin, flesh, sinews, and bones, resulting in redness, swelling, pain, and heaviness, forming "Hong Kong Foot." The two are distinct, like wind and horses meeting cattle—they have nothing in common. However, some cases arise from internal factors, caused by excessive alcohol consumption and ingestion of dairy products like milk and cheese. Others result from external invasion by wind, rain, fog, and dew. Some occur neither from within nor without but are due to the qi stagnation of obese and robust individuals. These may involve downward pouring of damp-phlegm or downward flowing of yin-fire. The situations are varied, but treatment should primarily focus on dispelling dampness and clearing heat, followed by nourishing blood and cooling blood, and then relaxing sinews and removing dryness. If one does not distinguish appropriate treatments, differentiate living environments, observe the patient's strength or weakness, and regulate their qi and blood, but instead indiscriminately administer Er Miao San (Two Marvels Powder), it is unlikely to fulfill the expectations of the formula. So, what should be done?
Cangzhu Chushi Tang (Atractylodes Decoction for Dispelling Dampness):
Shancao Cangzhu (Mao Mountain Atractylodis Rhizoma, 1 qian, processed with rice wash water) Huangbai (Phellodendri Cortex, 0.7 qian, stir-fried with wine) Shengdi (Rehmanniae Radix, 1 qian) Xuan Mugua (Chaenomelis Fructus, 1 qian) Yiyiren (Coicis Semen, 2 qian) Niuxi (Achyranthis Bidentatae Radix, 1 qian) Danggui (Angelicae Sinensis Radix, 1 qian) Du Huo (Angelicae Pubescentis Radix, 0.7 qian) Guangpi (Citri Reticulatae Pericarpium, 0.8 qian) Fuling (Poria, 1 qian)
Add a handful of Jiaxin (Thomson's Rush Pith) and one slice of Shengjiang (Zingiberis Rhizoma Recens). Decoct in water. For those who drink alcohol, add Gegen (Puerariae Lobatae Radix) and Zexie (Alismatis Rhizoma), each 1 qian, or add Han Fangji (Stephaniae Tetrandrae Radix).
Baizhu Tang (Atractylopsis Macrocephala Decoction): Treats pain in the shins and feet caused by deficiency of qi and blood.
Baizhu (Atractylodis Macrocephalae Rhizoma, 1 qian, stir-fried with soil) Renshen (Ginseng Radix et Rhizoma, 1 qian) Fuling (Poria, 1 qian) Niuxi (Achyranthis Bidentatae Radix, 1 qian)
Huangbai (Phellodendri Cortex, 1 qian) Cangzhu (Atractylodis Rhizoma, 0.7 qian, processed with rice wash water) Danggui (Angelicae Sinensis Radix, 1 qian) Baishao Yao (Paeoniae Radix Alba, 1 qian, stir-fried with wine) Mugua (Chaenomelis Fructus, 1 qian) Chaihu (Bupleuri Radix, 0.5 qian) Guangpi (Citri Reticulatae Pericarpium, 1 qian)
Add two dates and one slice of ginger. Decoct in water.
Danxi treated women's shin and foot pain using:
Honghua (Carthami Flos) Niuxi (Achyranthis Bidentatae Radix) (both washed with wine) Shengdi (Rehmanniae Radix) Huangbai (Phellodendri Cortex) Cangzhu (Atractylodis Rhizoma) Nanxing (Arisaematis Rhizoma) Longdan Cao (Gentianae Radix) Chuanxiong (Ligustici Chuanxiong Rhizoma)
Decoct in water and take orally.
To treat soft feet and painful sinews, he used:
Niuxi (Achyranthis Bidentatae Radix, 2 liang) Baishao Yao (Paeoniae Radix Alba, 1.5 liang) Guiban (Testudinis Carapax et Plastrum, roasted with wine) Banban (Platycladi Cacumen, stir-fried with wine, each 1 liang) Zhimu (Anemarrhenae Rhizoma, stir-fried) Gancao (Glycyrrhizae Radix et Rhizoma, each 5 qian)
Grind into powder, make pills with wine paste.
Er Miao Wan (Two Marvels Pill):
Cangzhu (Atractylodis Rhizoma, 2 liang, soaked in rice wash water and stir-fried) Huangbai (Phellodendri Cortex, 2 liang, stir-fried with wine)
Grind into powder, make pills with Shenqu paste.
Huantui Wan (Leg-Swapping Pill): Treats conditions where the three yin meridians of the foot are attacked by wind, cold, summer-heat, and dampness, leading to contracture, bi-syndrome, flaccidity, or upward attack on the chest and back, downward pouring to the feet and knees, causing pain, fever, and difficulty walking.
Yiyiren (Coicis Semen) Nanxing (Arisaematis Rhizoma) Shi Nanye (Foliage of Euryale Salacii) Shihu (Dendrobii Caulis) Binglang (Arecae Semen) Bixie (Dioscoreae Hypoglaucae Rhizoma) (mixed with wine) Niuxi (Achyranthis Bidentatae Radix) (soaked in wine) Qiang Huo (Notopterygii Rhizoma et Radix) Fangfeng (Saposhnikoviae Radix) Mugua (Chaenomelis Fructus) (each 4 liang)
Huangqi (Astragali Radix) (honey-roasted) Danggui (Angelicae Sinensis Radix) (mixed with wine) Ming Tianma (Gastrodiae Rhizoma) Xuduan (Dipsaci Radix) (stir-fried with wine, each 1 liang)
Grind all above into powder, make pills with wine paste, size of tung seeds. Take 50 pills per dose, swallowed with salt water.