诸阳经络循于头，三阴则至项而还。头汗者，邪搏诸阳，则汗见于头也。若遍身汗者，为之热
越。今热不得越而阳气上腾，津液上凑，故但头汗耳。夫里虚则不可下，内涸则不宜汗。头汗之证，
更不可再汗也。其或瘀血在里，与夫热入血室，虚烦水结，皆令头汗。此为热郁于内而上达，或吐
或下，以祛其邪。设或小便不利，内外关格而头汗，则为阳脱。误下湿家，额上汗出而喘，小便难，
小便利，亦为阳脱。二者皆不疗矣。《百问》∶表实里虚。故头汗不可下。
发黄，头汗及项而止，小便难，引水浆，此湿也，茵陈蒿、茵陈五苓散。
心结胸，心忪满，无大热，头汗出，半夏茯苓汤。
谵语头汗，是为血热，属阳明，用承气汤。若心中懊 而头汗者，栀子豉汤。
半表半里，有柴胡证，并小柴胡汤。热寒往来，微恶寒，为表。胁下满，大便坚，为里。
四肢者，诸阳之本，热聚于胃，则津液旁达于手足也。蕴热，则躁烦谵语，挟寒，则水谷不分。
是又承气、理中之不同。
阳明病，手足 汗出，谵语，大便难，与承气汤。阳明中寒，不能食，小便不利，手足汗出，
大便初硬后溏，水谷不分，与理中汤。一法用猪苓汤。
盗汗者，睡着则汗出，觉则便不出矣。杂病责于阳虚，伤寒责在半表半里，故知
胆有热也。
阳明病，脉浮紧，潮热盗汗，柴胡桂枝汤。脉浮大，欲眠，目合则汗，小柴胡汤，又柴胡桂枝
汤。
诸阳经的经络循行于头部，而三阴经则到达颈部后返回。头汗症，是由于邪气搏结于诸阳经，导致汗液出现在头部。如果全身出汗，称为热邪向外发散。如今热邪不能向外发散，反而阳气上腾，津液向上汇聚，所以只有头部出汗。体内虚弱则不可使用攻下法，内部枯竭则不宜使用发汗法。头汗证，更不可再次发汗。那些瘀血在体内，以及热邪陷入血室，虚烦水结等情况，都会导致头汗。这是因为热邪郁结在内部而上达头部，或者通过催吐或攻下，来祛除病邪。假如小便不利，内外格拒而导致头汗，则是阳气外脱的表现。误用攻下法治疗湿病患者，出现额头出汗且气喘，小便困难，即使小便利，也属于阳气外脱。这两种情况都难以治愈。《百问》说：表实里虚。所以头汗不可使用攻下法。
身体发黄，头汗仅到颈部为止，小便困难，想喝水浆，这是湿邪所致，可用茵陈蒿汤、茵陈五苓散。
心部结胸，心中悸动胀满，没有大热，头部出汗，可用半夏茯苓汤。
说胡话且头部出汗，这是血热，属于阳明病，用承气汤。如果心中懊恼且头部出汗，用栀子豉汤。
病在半表半里，有柴胡证，并用小柴胡汤。发热恶寒交替往来，轻微怕冷，属于表证。胁下胀满，大便坚硬，属于里证。
四肢是诸阳经的根本，热邪聚集在胃中，则津液旁达于手足。蕴积热邪，则烦躁说胡话；夹杂寒邪，则水谷不分。这又是承气汤与理中汤的不同之处。
阳明病，手足出汗，说胡话，大便困难，给予承气汤。阳明中寒，不能进食，小便不利，手足出汗，大便初硬后稀，水谷不分，给予理中汤。另一种方法是用猪苓汤。
盗汗，是指睡着时出汗，醒来后汗就停止了。杂病责之于阳虚，伤寒责之于半表半里，因此知道胆有热邪。
阳明病，脉浮紧，潮热盗汗，用柴胡桂枝汤。脉浮大，想睡觉，闭上眼睛就出汗，用小柴胡汤，或者柴胡桂枝汤。
The meridians of all Yang channels circulate on the head, while the three Yin channels reach the nape and return. Head sweating (Tou Han) occurs when pathogens contend with the Yang channels, causing sweat to appear on the head. If sweat covers the entire body, it is called "heat venting" (Re Yue). Now, since heat cannot vent outward but Yang Qi ascends, and body fluids gather upward, only the head sweats. When the interior is deficient, purgation is contraindicated; when internal fluids are depleted, diaphoresis is inadvisable. In cases of head sweating, further diaphoresis must not be applied. Conditions such as blood stasis in the interior, heat entering the Blood Chamber (Xue Shi), deficiency vexation with water accumulation, all cause head sweating. This results from heat constrained internally reaching upward; treatment involves emesis or purgation to expel the pathogen. If urination is difficult, and there is internal-external blockage leading to head sweating, it indicates collapse of Yang Qi (Yang Tuo). Misusing purgation on patients with dampness, resulting in forehead sweating with wheezing and difficulty urinating, or even if urination becomes free, also signifies collapse of Yang Qi. Both conditions are considered untreatable. *Bai Wen* states: Exterior excess with interior deficiency. Therefore, head sweating should not be treated with purgation.
Jaundice with head sweating stopping at the neck, difficulty urinating, and craving fluids indicate dampness; use Yinchen Hao Tang (Artemisiae Scopariae Decoction) or Yinchen Wuling San (Artemisiae Scopariae and Five-Ingredient Poria Powder).
Chest binding (Jie Xiong) in the heart region, palpitations and fullness without significant fever, and head sweating can be treated with Banxia Fuling Tang (Pinellia and Poria Decoction).
Delirium with head sweating indicates blood heat belonging to the Yangming channel; use Chengqi Tang (Chengqi Decoction). If there is profound stifling sensation in the chest with head sweating, use Zhizi Chi Tang (Gardenia and Fermented Soybean Decoction).
For half-exterior half-interior patterns with Chaihu syndrome, use Xiao Chaihu Tang (Minor Bupleurum Decoction). Alternating fever and chills with slight aversion to cold indicate an exterior pattern. Fullness under the costal margin and hard stool indicate an interior pattern.
The four limbs are the root of all Yang channels. Heat accumulating in the Stomach causes body fluids to distribute laterally to the hands and feet. Accumulated heat leads to restlessness and delirium; combined with cold, it leads to indistinguishability of food and water. This distinguishes the applications of Chengqi Tang from Lizhong Tang.
In Yangming disease, with sweating of the hands and feet, delirium, and difficulty defecating, administer Chengqi Tang. In Yangming cold-dampness, with inability to eat, difficulty urinating, sweating of the hands and feet, initially hard then loose stools, and indistinguishability of food and water, administer Lizhong Tang (Regulate the Middle Decoction). Alternatively, use Zhuling Tang (Polyporus Decoction).
Night sweating (Dao Han) refers to sweating during sleep that stops upon waking. For miscellaneous diseases, this is attributed to Yang deficiency; for Shanghan (Cold Damage), it is attributed to the half-exterior half-interior level, indicating heat in the Gallbladder.
In Yangming disease, with a floating-tight pulse, tidal fever, and night sweating, use Chaihu Guizhi Tang (Bupleurum and Cinnamon Twig Decoction). With a floating-large pulse, drowsiness, and sweating upon closing the eyes, use Xiao Chaihu Tang or Chaihu Guizhi Tang.