阴阳别论云二阳结谓之消脉要精微论云瘅成为消中夫二阳者阳明也手阳明大肠主津病消
则目
黄口干是津不足也足阳明胃主血热则消谷善饥血中伏火乃血不足也结者津液不足结而不润皆
燥热为病也此因数食甘美而多肥故其气上溢转为消渴治之以兰除陈气也不可服膏粱芳草石
药其气剽悍能助燥热也越人云邪在六腑则阳脉不和阳脉不和则气留之气留之则阳脉盛矣阳脉
大盛则阴气不得荣也故皮肤肌肉消削是也经云
凡治消瘅仆系偏枯痿厥气满发逆肥贵人则膏粱之疾也岐伯曰脉实病久可治脉弦小病久不可治
后
分为三消高消者舌上赤裂大渴引饮逆调论云心移热于肺传于膈消者是也以白虎加人参汤治之
中消者善食而瘦自汗大便硬小便数叔和云口干饮水多食亦肌虚瘅成消中者是也以调胃承气三
黄丸治之下消者烦躁引饮耳叶焦干小便如膏叔和云焦烦水易亏此肾消也以六味地黄丸治之总
录所谓末传能食者必发脑疽背疮不能食者必传中满鼓胀皆谓不治之证洁古老人分而治之能食
而渴者白虎加人参汤不能食而渴者钱氏方白术散倍加葛根治之上中既平不复传下消矣前人用
药厥有旨哉或曰未传疮疽者何也此火邪胜也其疮痛甚而不溃或赤水者是也经云有形而不痛阳
之类也急攻其阳无攻其阴治在下焦元气得强者生失强者死未传中满者何也以寒治热虽方士不
能废其绳墨而更其道也然脏腑有远近心肺位近宜制小其服肾肝位远宜制大其服皆适其至所为
故知过与不及皆诛罚无过之地也如高消中消制之太急速过病所久而成中满之病正谓上热未除
中寒复生者也非药之罪失其缓急之制也处方之制宜加意焉。
《阴阳别论》中说：“二阳结，谓之消。”《脉要精微论》中说：“瘅成为消中。”所谓“二阳”，指的是阳明经。手阳明大肠经主管津液，患消渴病时出现目黄、口干的症状，这是津液不足的表现；足阳明胃经主管血液，热盛则消化食物过快而容易饥饿，血中潜伏火邪导致血不足。“结”意味着津液亏少，凝结而不滋润，这都是燥热致病的原因。这是因为长期食用甘甜美味且多油脂的食物，导致气机上溢，转化为消渴病。治疗应当用兰草（佩兰）来清除陈腐之气。不可服用膏粱厚味、芳草类或石类药物，因为这些药性剽悍猛烈，会助长燥热。
《难经》说：“邪气在六腑，则阳脉不和。”阳脉不和，则气机留滞；气机留滞，则阳脉盛大。阳脉盛大，阴气就无法荣养身体，所以皮肤肌肉消瘦削薄。经文说：“凡是治疗消瘅、仆击、偏枯、痿厥、气满发逆等病症，多见于富贵之人，这是膏粱厚味引起的疾病。”岐伯说：“脉象实大，病程虽久也可治；脉象弦小，病程久则难治。”
后来将消渴分为三消：
上消（高消）：舌面红裂，极度口渴想喝水。《逆调论》说：“心移热于肺，传于膈消。”用白虎加人参汤治疗。
中消：吃得多却身体消瘦，自汗出，大便干硬，小便频数。王叔和说：“口干，饮水多，吃得多但肌肉虚弱，瘅热形成消中。”用调胃承气汤和三黄丸治疗。
下消（肾消）：烦躁引饮，耳廓干枯焦黑，小便像膏脂一样浑浊。王叔和说：“焦烦，水液易枯竭，这是肾消。”用六味地黄丸治疗。
《总录》记载：如果病情发展到末期，能吃东西的必然发生脑疽、背疮；不能吃东西的必然发展为中满鼓胀，这些都是不治之证。洁古老人分别施治：能进食且口渴的，用白虎加人参汤；不能进食且口渴的，用钱乙的方子白术散，加倍加入葛根治疗。上消和中消治愈后，就不会再传变为下消了。前人用药确实很有深意。
有人问：“为什么没有发展成疮疽呢？”这是因为火邪胜盛所致。疮疡疼痛剧烈但不溃破，或者流出赤色脓水的，就是这种情况。经文说：“有形质但不痛的，属于阳证。”应当急攻其阳分，不要攻其阴分。治疗在下焦，元气强健的能生，元气虚弱的则死。
为什么没有发展成中满呢？用寒凉药治疗热证，虽然是医家的常规法则，不可废弃，但脏腑有远近之分：心肺位置近，药量宜小；肝肾位置远，药量宜大，都要使药力恰好到达病所。因此，用药过多或过少，都会惩罚无病的部位。比如上消、中消，如果制方太急，药力超过病所，久而久之就会形成中满的病证。这正是所谓的“上部的热邪未除，中部的寒邪又生”。这不是药的过错，而是失去了缓急适度的法度。处方用药必须仔细斟酌。
The *Treatise on Differences in Yin and Yang* states: "Obstruction of the Two Yangs is called Xiao (Wasting-Thirst)." The *Essential Secrets of the Pulse Essentials* states: "Dan heat transforms into Xiao Zhong (Middle Wasting-Thirst)." The "Two Yangs" refer to the Yangming Meridians. The Hand-Yangming Large Intestine Meridian governs body fluids; when suffering from Xiao, symptoms such as yellow eyes and dry mouth indicate a deficiency of fluids. The Foot-Yangming Stomach Meridian governs blood; excessive heat leads to rapid digestion and hunger, while latent fire in the blood causes blood deficiency. "Obstruction" implies insufficient body fluids that fail to moisten, all resulting from dryness-heat pathologies. This arises from long-term consumption of sweet, delicious, and fatty foods, causing Qi to overflow upward and transform into Xiao (Wasting-Thirst). Treatment should employ Lan Cao (Pei Lan, *Herba Menthae Haplocalycis*) to eliminate stale Qi. One must not consume rich meats or aromatic herbs and mineral drugs, as their fierce nature can aggravate dryness-heat.
The *Nan Jing* (Classic of Difficult Issues) states: "When pathogens reside in the Six Fu Organs, the Yang pulses are discordant." Discordance in Yang pulses leads to Qi stagnation; Qi stagnation causes the Yang pulses to become vigorous. When Yang pulses are excessively vigorous, Yin Qi fails to nourish the body, resulting in emaciation of skin and muscles. The Classics state: "In treating Xiao Dan (Wasting-Thirst), Pu Ji (Sudden Collapse), Pian Gu (Hemiplegia), Wei Jue (Atrophy and Cold Extremities), and Qi Man Fa Ni (Fullness and Rebellious Qi), these conditions often affect wealthy individuals and are diseases caused by rich diets." Qibo stated: "If the pulse is full and the disease has lasted long, it is treatable; if the pulse is wiry and small and the disease has lasted long, it is difficult to treat."
Later, Xiao was categorized into Three Xiaos:
Upper Xiao (Gao Xiao): Red cracks on the tongue, extreme thirst with desire to drink. The *Treatise on Counterflow and Regulation* states: "Heart heat transfers to the Lung, transforming into Ge Xiao (Diaphragm Wasting-Thirst)." It is treated with Bai Hu Jia Ren Shen Tang (White Tiger Decoction plus Ginseng).
Middle Xiao: Polyphagia with emaciation, spontaneous sweating, hard stools, and frequent urination. Wang Shuhe stated: "Dry mouth, excessive drinking, polyphagia but weak muscles, where Dan heat forms Xiao Zhong." It is treated with Tiao Wei Cheng Qi Tang (Regulate the Stomach Order the Qi Decoction) and San Huang Wan (Three Yellows Pill).
Lower Xiao (Shen Xiao): Irritability with thirst, dried and scorched earlobes, urine resembling paste. Wang Shuhe stated: "Scorched irritability, fluid depletion easily occurs; this is Kidney Xiao." It is treated with Liu Wei Di Huang Wan (Six-Ingredient Rehmannia Pill).
The *Zong Lu* records: If the condition progresses to the terminal stage, those who can eat will inevitably develop brain abscesses or back sores; those who cannot eat will inevitably develop abdominal fullness and distension. These are considered incurable. Elder Jiegu treated them separately: for those who can eat and feel thirsty, use Bai Hu Jia Ren Shen Tang; for those who cannot eat and feel thirsty, use Qian Shi's Fang Zi San (Bai Zhu Powder) with added Ge Gen (Kudzu Root). Once Upper and Middle Xiao are resolved, transmission to Lower Xiao ceases. The previous masters' use of medicine was indeed profound.
One might ask: "Why did it not progress to sores?" This is due to victorious Fire pathogens. The sores are painful but do not suppurate, or they discharge red fluid. The Classics state: "Having form but no pain belongs to the Yang category." One should urgently attack the Yang aspect, not the Yin aspect. Treatment focuses on the Lower Jiao; survival depends on strong Yuan Qi, while death follows if Yuan Qi is weak.
Why did it not progress to abdominal fullness? Using cold to treat heat follows standard medical principles, which cannot be discarded. However, Zang-Fu organs have varying distances from the surface: Heart and Lung are proximal, requiring smaller doses; Liver and Kidney are distal, requiring larger doses. The dosage must ensure the medicine reaches the target site. Therefore, both excess and deficiency in dosage punish healthy tissues. For instance, in Upper and Middle Xiao, if the prescription is too rapid or potent, exceeding the pathological site, it may eventually cause abdominal fullness. This is precisely what is meant by "upper heat not yet removed, middle cold newly generated." This is not the fault of the medicine, but a failure in balancing speed and moderation. Prescribing requires careful consideration.