须、鬓、阴、腋诸毛详前三阳上下气血多少篇，兹不复赘。
肺主身之皮毛。肾合三焦膀胱。三焦膀胱者，腠理毫毛其应。五脏伤败，毛悴色夭者，死于脏气所不胜
之时也。手太阴者，行气而温于皮毛者也。故气绝则不荣皮毛，皮毛焦则津液去，皮节爪枯毛折。手少阴气绝
则脉不通，脉不通则血不流，血不流则髦色不泽。足少阴者，伏行而濡骨髓者也。气绝则骨不濡，肉不能着
也。骨肉不相亲则肉软却，故齿长而垢，发无泽。肾，其华在发，故丈夫八岁肾气实，齿更发长。五八肾气
衰，发堕齿枯。（以上《内经》。）
发者血之余也。心与小肠主血，故小肠绝者，发干直如麻，不得曲伸。小儿病，其头毛皆上逆者死。
其发枯黄者，心肾血气俱不足也。（以上《脉经》。）
足厥阴肝脉与督脉会于巅，故勇士之怒，发立上指。平人肝热，其气上冲，头皮一块肿痛，发根
为之粗硬而逆起。（以下四节添加。）
平人眉忽生一长毫，异于众毛，拔之三、五日复生者，胆
中血热也。在小儿必生急风。《脉经》曰∶胆绝，眉为之倾。
平人鼻中忽生一长毫，粗硬异于众毛者，肺中血热也。拨之三、五日即复生，久不治，即生肺痈发
背。夏子益《奇疾方》有鼻生长毫，硬如铁丝，触之其痛彻心，为肺大热也。
发通五脏，而尤切于心肾。故病温疫热毒，及服毒药，
与饮酒大醉者，以冷水浸其发。又喉蛾急疗等证，察有赤发者，急拔之，是热血上逆也。
胡须、鬓角、阴部及腋下的毛发情况，详见前文“三阳经上下气血多少篇”，此处不再赘述。
肺主管全身的皮毛。肾与三焦、膀胱相表里。三焦和膀胱的功能反映在腠理（皮肤纹理）和毫毛上。如果五脏受损败坏，出现毛发憔悴、面色枯槁无华的症状，患者会在被脏气所克制的时辰死亡。手太阴肺经，负责输送气并使皮毛得到温煦。因此，肺气衰竭就不能滋养皮毛，皮毛干枯则津液流失，导致皮肤、关节、指甲枯萎，毛发折断。手少阴心经气绝，则脉道不通；脉道不通则血液不流通；血液不流通则眉毛头发失去光泽。足少阴肾经，潜行体内以濡养骨髓。肾气衰竭则骨骼得不到濡养，肌肉无法附着于骨。骨肉不相亲附，则肌肉松弛萎缩，所以牙齿显得变长且积垢，头发失去光泽。肾的精气外现于头发，所以男子八岁时肾气充实，牙齿更换，头发生长。四十岁（五八）时肾气开始衰退，头发脱落，牙齿枯槁。（以上引用自《黄帝内经》。）
头发是血液的余气所化。心与小肠主司血液，因此小肠气绝的人，头发干枯笔直如麻草，不能弯曲伸展。小儿患病，如果头部的毛发全部向上逆立，是死证。如果头发枯黄，说明心和肾的气血都不足。（以上引用自《脉经》。）
足厥阴肝经与督脉交会于头顶，所以勇士发怒时，头发竖立指向天空。普通人如果肝热，热气上冲，会导致头皮局部肿痛，发根变得粗硬而逆起。（以下四节为添加内容。）
普通人眉毛中突然长出一根比周围毛发都长的毫毛，拔掉后三到五天又长出来，这是胆中有血热的表现。在小儿身上出现这种情况，必定会患上急风病（惊风）。《脉经》说：胆气绝，眉毛会倾倒歪斜。
普通人鼻孔中突然长出一根比周围毛发粗硬异样的长毫毛，拔掉后三到五天又长出来，如果长期不治疗，就会发展成肺痈或发背（背部痈疽）。夏子益的《奇疾方》记载，鼻中长出像铁丝一样硬的长毫毛，触碰时疼痛彻心，这是由于肺中大热所致。
头发贯通五脏，尤其与心、肾关系密切。因此，患温热疫病热毒，或服用毒药，以及饮酒大醉的人，可以用冷水浸泡头发。另外，对于喉蛾（扁桃体炎）、急疗等病症，如果发现伴有赤色毛发，应立即拔除，这是因为热血上逆所致。
The condition of the hair on the beard, temples, genitals, and axillae is detailed in the previous section "On the Abundance and Scarcity of Qi and Blood in the Three Yang Meridians," so it will not be repeated here.
The Lung governs the skin and body hair (maomao). The Kidney combines with the Sanjiao (Triple Burner) and Bladder. The Sanjiao and Bladder manifest their function through the interstices (coulī) and fine body hair. If the Five Viscera are damaged and deteriorated, presenting with emaciated hair and a sallow, lifeless complexion, death occurs during the time when the controlling organ's qi is at its peak. The Hand-Taiyin Lung Meridian circulates Qi and warms the skin and hair. Therefore, when Lung Qi fails, it cannot nourish the skin and hair; if the skin and hair become dry, body fluids are lost, leading to withered skin, joints, nails, and broken hair. When Heart Qi of the Hand-Shaoyin Meridian fails, the vessels become obstructed; obstruction leads to stagnant blood; stagnant blood results in a lack of luster in the eyebrows and hair. The Foot-Shaoyin Kidney Meridian runs deep within to moisten the bone marrow. When Kidney Qi fails, the bones are not moistened, and muscles cannot adhere to them. When flesh and bone lose their affinity, the muscles become flaccid and recede, causing the teeth to appear elongated and covered with tartar, and the hair to lose its luster. The Kidney manifests its splendor in the hair; thus, at age eight, a man's Kidney Qi becomes substantial, his teeth change, and his hair grows. At age forty (five times eight), his Kidney Qi begins to decline, his hair falls out, and his teeth become withered. (Above from *Neijing*.)
Hair is the surplus of Blood. The Heart and Small Intestine govern Blood; therefore, when Small Intestine Qi fails, the hair becomes dry, straight like hemp, and unable to bend or stretch. In children with illness, if all the hair on the head stands upright, it indicates a fatal condition. If the hair is withered and yellow, it indicates insufficiency of Qi and Blood in both the Heart and Kidney. (Above from *Maijing*.)
The Foot-Jueyin Liver Meridian intersects with the Du Meridian at the vertex; thus, when a brave person is angry, their hair stands erect pointing upward. In ordinary people, Liver Heat causes Qi to rush upward, resulting in localized swelling and pain on the scalp, where the hair roots become coarse, hard, and stand on end. (The following four sections are additions.)
If an ordinary person suddenly grows a single long hair among the eyebrows that differs from the surrounding hairs, which regrows three to five days after plucking, this indicates Heat in the Blood of the Gallbladder. In children, this must lead to Ji Feng (acute wind/convulsions). *Maijing* states: "When Gallbladder Qi fails, the eyebrows collapse."
If an ordinary person suddenly grows a single long hair in the nose that is coarser and harder than the surrounding hairs, which regrows three to five days after plucking, this indicates Heat in the Blood of the Lung. If left untreated for a long time, it may develop into Fei Yong (lung abscess) or Fa Bei (back carbuncle). Xia Zi Yi's *Qiji Fang* records cases of long hairs growing in the nose, hard as iron wire, causing heart-piercing pain upon touch, which is due to severe Heat in the Lung.
Hair connects with the Five Viscera, particularly closely with the Heart and Kidney. Therefore, in cases of warm epidemic heat-toxin, ingestion of toxic drugs, or severe alcohol intoxication, one should soak the hair in cold water. Additionally, in conditions such as Hou E (tonsillitis) and Ji Liao (acute boils), if red hairs are observed, they should be plucked immediately, as this indicates the counterflow of hot blood.