香港脚皆由湿热所致。经曰∶伤于湿者，下先受之。湿郁成热，湿热相搏，其病生矣。然湿有因外
而得者，有自内而生者，其致病不同，见症则一。发热恶寒，或亦头痛，状若伤寒，但起于脚胫红肿，筋
挛掣痛，举步艰难为异耳。轻者，止于足痛，重者，由足痛入阴器，抵少腹，历胁肋上头。又重者，则
香港脚冲心，神昏谵语，喘急不止，呕吐不休，每多致毙。治宜清热除湿利水为主。盖香港脚之疾壅疾也。喜
通而恶塞，故孙真人云∶香港脚病皆由气实而死，终无一人以服药
致虚而死。仲淳论治香港脚，忌用补气温燥升提等药，然又不可大泻，及纯用破气之剂。按《金匮》治香港脚
上入，少腹不仁，责之寒湿上逆，痹着少腹，用八味丸以壮真阳，逐寒湿。然香港脚之属寒湿者绝少，
误投温热，必立致祸，审之慎之。昔人论香港脚之原本于湿，若因外而得者，如涉水骤雨，居处卑湿，足
先受之，湿郁为热，故发动为痛；自内而生者，如饮食之湿，酒水瓜果乳酪，有湿有热，先入于胃，
上输于脾，脾主四肢，水性就下，故脾流湿热，直入于足。总之香港脚病以肿为湿，痛为热，乃不易之论也。
防己饮〔重订。〕治湿热在足，脚胫红肿，〔亦有不红者。〕筋挛掣痛，发热恶寒，主此加减。
汉防己〔通下焦湿热，壅遏香港脚，非此不除。钱许。〕黄柏〔治下焦湿热肿痛。二
钱。〕忍冬花〔疗香港脚筋骨引痛。鲜藤数两，煎汤代水更效。〕川萆 〔祛浊厘清。各五
钱。〕木瓜〔祛湿舒筋，〕白茯苓〔各三钱。〕泽泻 木通〔利水除湿，各钱许。〕石
斛米仁〔益脾除湿。各五钱。〕如红肿加犀角，冲心烦闷，亦用。再加槟榔〔降气下
行。〕羚羊角〔下逆气治热闷。〕如喘呕，加麦冬 枇杷叶。如头痛加甘菊。
此清热除湿利水之剂，香港脚皆由湿热，通宜以此方为主，随兼症而扩充以加减之则善。
《金匮》矾石汤 治香港脚冲心。〔湿热之气，上冲于心，即地气加天之谓也。〕
白矾〔收湿澄浊，清热解毒。四两。〕煎汤浸脚。〔使
湿热不上冲。〕可加苦参〔四钱。〕
香港脚（一种以足胫红肿疼痛为主要特征的疾病）皆由湿热邪气所致。《内经》说：受湿邪侵袭，病邪往往先从下部受到侵害。湿气郁结而化热，湿热相互搏结，疾病便产生了。然而，湿邪有因外感而得的，也有因内生而起的，它们致病的原因不同，但表现出的症状却是一致的。（患者出现）发热、怕冷，有时也伴有头痛，症状看起来像伤寒，但区别在于起病于足胫部的红肿，筋脉拘挛牵引作痛，抬腿行走困难。轻症的，仅限于足部疼痛；重症的，由足部疼痛蔓延至阴器，直达少腹，经过胁肋向上至头部。更重的，则发展为香港脚冲心（湿热之邪上攻于心），出现神志昏迷、胡言乱语，气喘急促不止，呕吐不停，常常导致死亡。治疗应当以清热、除湿、利水为主。因为香港脚这种病属于壅滞急迫之疾，喜好通畅而厌恶闭塞，所以孙思邈说：香港脚病多因气实（邪气盛实）而死，从来没有一个人因为服药导致正气虚损而死的。陈实功（字仲淳）论述治疗香港脚时，忌讳使用补气温燥、升提类药物，然而也不可以过度泻下，以及单纯使用破气耗气的方剂。按照《金匮要略》记载，治疗香港脚邪气上逆，少腹部感觉麻木不仁，责之于寒湿上逆，痹阻于少腹，使用八味丸（即肾气丸）来壮真阳，驱逐寒湿。然而，属于寒湿类型的香港脚极少见，误投温热药物，必定立即招致祸患，务必审慎辨别。前人论述香港脚的根源在于湿，如果是外感所得的，如涉水、骤雨、居住在低洼潮湿之处，足部先受湿邪，湿气郁结化为热，所以发作时产生疼痛；如果是内生湿邪，如饮食中的湿气，酒水、瓜果、乳酪等，既有湿又有热，先进入胃中，向上输布给脾，脾主四肢，水性向下，所以脾流转化的湿热，直接流入足部。总之，香港脚病以肿胀为湿，以疼痛为热，这是不可更改的定论。防己饮（重订版）治疗湿热在足部，足胫红肿，（也有不红的情况），筋脉拘挛牵引作痛，发热恶寒，主治此证并随症加减。汉防己（能通利下焦湿热，壅遏的香港脚非此药不能清除，钱乙推崇），黄柏（治疗下焦湿热肿痛，二钱），忍冬花（治疗香港脚筋骨牵引疼痛，鲜藤数两，煎汤代替水煎煮效果更佳），川萆薢（祛浊厘清，各五钱），木瓜（祛湿舒筋），白茯苓（各三钱），泽泻、木通（利水除湿，各一钱左右），石斛、薏苡仁（益脾除湿，各五钱）。如果红肿，加犀角，冲心烦闷时也使用。再加槟榔（降气下行），羚羊角（降逆气治疗热闷）。如果出现气喘呕吐，加麦冬、枇杷叶。如果头痛，加甘菊。这是一个清热、除湿、利水的方剂，香港脚皆由湿热引起，通常适宜以此方为主，根据兼夹症状进行扩充和加减，这样疗效才好。《金匮要略》矾石汤治疗香港脚冲心。（湿热之气上冲于心，即地气加天气的意思。）白矾（收敛湿气、澄清浊邪、清热解毒，四两），煎汤浸泡双脚。（使湿热不上冲。）可以加苦参（四钱）。
Hong Kong foot (a disease characterized mainly by redness, swelling, and pain in the lower legs) is caused entirely by damp-heat pathogenic factors. The *Classic of Internal Medicine* states: "When injured by dampness, the lower part of the body is affected first." Dampness stagnates and transforms into heat; when dampness and heat contend with each other, the disease arises. However, dampness can be acquired externally or generated internally. Although their causes differ, the manifested symptoms are consistent. The patient presents with fever and aversion to cold, sometimes accompanied by headache, resembling Taiyang syndrome (Cold Damage), but differs in that it originates with redness and swelling of the shins, tendon spasms and pulling pain, and difficulty in walking. In mild cases, the pain is confined to the feet; in severe cases, the pain spreads from the feet to the genitalia, reaches the lower abdomen, passes through the hypochondrium, and ascends to the head. In even more severe cases, it develops into Hong Kong foot rushing to the heart (damp-heat pathogenic factors attacking the Heart upwards), presenting with coma, delirium, incessant panting, and continuous vomiting, often leading to death. Treatment should primarily focus on clearing heat, removing dampness, and promoting urination. This is because Hong Kong foot is a condition of obstruction and urgency; it favors free flow and abhors blockage. Therefore, Sun Simiao stated: "Hong Kong foot patients die due to excess Qi (pathogenic excess), never due to deficiency caused by medication." Chen Shigong (courtesy name Zhongchun) discussed the treatment of Hong Kong foot, warning against the use of tonifying, warming, drying, and ascending drugs. However, one must also avoid excessive purging or the exclusive use of Qi-breaking formulas. According to the *Jin Gui Yao Lue*, for Hong Kong foot with upward invasion causing numbness in the lower abdomen, the cause is attributed to cold-dampness reversing upward and obstructing the lower abdomen. Eight-Ingredient Pill (Ba Wei Wan, i.e., Shen Qi Wan) is used to strengthen True Yang and expel cold-dampness. However, Hong Kong foot caused by cold-dampness is extremely rare; misusing warm-hot medicines will inevitably lead to disaster, so careful differentiation is essential. Ancients discussed that the root of Hong Kong foot lies in dampness. If acquired externally, such as wading in water, sudden rain, or dwelling in low, damp places, the feet are affected first; dampness stagnates and transforms into heat, causing pain upon onset. If generated internally, such as dampness from diet, including alcohol, fruits, melons, milk, and cheese, which contain both dampness and heat, it enters the Stomach first, then transports upward to the Spleen. The Spleen governs the four limbs, and water nature flows downward; thus, damp-heat transformed by the Spleen flows directly into the feet. In summary, in Hong Kong foot, swelling indicates dampness, and pain indicates heat; this is an unchangeable principle. Fang Ji Yin (Revised Edition) treats damp-heat in the feet, with redness and swelling of the shins (sometimes without redness), tendon spasms and pulling pain, fever, and aversion to cold. It is indicated for this pattern with modifications. Han Fang Ji (Tetrandrae Radix, unblocks damp-heat in the Lower Jiao, essential for resolving obstructed Hong Kong foot, praised by Qian Yi), Huang Bo (Phellodendri Cortex, treats damp-heat swelling and pain in the Lower Jiao, 2 qian), Ren Dong Hua (Lonicerae Flos, treats Hong Kong foot tendon and bone pulling pain; fresh vines, several liang, decocted in water instead of boiling yields better results), Chuan Bi Xie (Dioscoreae Hypoglaucae Rhizoma, removes turbidity and clarifies purity, 5 qian each), Mu Gua (Chaenomelis Fructus, removes dampness and relaxes tendons), Bai Fu Ling (Poria, 3 qian each), Ze Xie (Alismatis Rhizoma), Mu Tong (Akebiae Caulis, promotes urination and removes dampness, approx. 1 qian each), Shi Hu (Dendrobii Caulis), Yi Yi Ren (Coicis Semen, benefits the Spleen and removes dampness, 5 qian each). If there is redness and swelling, add Xi Jiao (Rhinocerotis Cornu); also used for chest oppression and irritability. Add further Bing Lang (Arecae Semen, directs Qi downward), Ling Yang Jiao (Saigae Tataricae Cornu, directs rebellious Qi downward and treats heat oppression). If panting and vomiting occur, add Mai Dong (Ophiopogonis Radix) and Pi Pa Ye (Eriobotryae Folium). If headache occurs, add Gan Ju (Chrysanthemi Flos). This is a formula for clearing heat, removing dampness, and promoting urination. Since Hong Kong foot is caused by damp-heat, this formula is generally suitable as the main prescription, expanded and modified according to accompanying symptoms for optimal efficacy. Jin Gui Yao Lue Fan Shi Tang treats Hong Kong foot rushing to the heart. (Damp-heat Qi rushing upward to the Heart, meaning earthy qi adding to heavenly qi.) Fan Shi (Alumina, astringes dampness, clears turbidity, and detoxifies, 4 liang). Decoct in water to soak the feet. (Prevents damp-heat from rushing upward.) Can add Ku Shen (Sophorae Flavescentis Radix, 4 qian).