人之所以滋养其身者，唯气与血。呼吸定息，卫气之常，失常则为咳嗽；津液流润，荣
血之常，失常则为痰涎。咳嗽吐痰，气血已乱矣。顾世治嗽之药极多，而卒不能遍效者，盖
其致病之因不一。世谓五嗽，且以五脏而言之，要之内因七情，外合六淫，饮食起居，房劳
叫呼，皆能单复倚互而为病。故《经》云∶五脏六腑，感寒热风湿，皆令人咳。又微寒微
咳，厉风所吹，声嘶发咳；热在上焦，咳为肺痿；秋伤湿，冬咳嗽，皆外所因。喜则气散，
怒则气激，忧则气聚，思则气结，悲则气紧，恐则气却，惊则气乱，皆能发咳，即内所因。
其如饮食生冷，房劳作役，致嗽尤多，皆不内外因。其可一法而治之?治之，当推其三因，
随脉证治疗，散之，下之，温之，吐之，以平为期。
伤风咳者，憎寒壮热，自汗恶风，口干烦躁；伤寒咳者，憎寒发热，无汗恶寒，烦躁不
渴；伤暑咳者，烦热引饮，口燥，或吐涎沫，声嘶咯血；伤湿咳者，骨节烦疼，四肢重着，
洒洒淅淅，并属外所因。诊其脉，浮为风，紧为寒，数为热，细为湿。随其部位，与人迎相
应；推其脏腑，则见病源也。
喜伤心者，咳而喉仲介介如肿状，甚则咽肿喉痹，名为心咳；不已，则小肠受之，小肠
咳状，与气俱失。怒伤肝者，咳而两胁下痛，甚则不可以转，转则两 下满，名为肝咳
；不已，则胆受之，胆咳之状，咳呕胆汁。思伤脾者，咳而右胁下痛，阴阴引肩背，甚则不
可以动，名为脾咳；不已，则胃受之，胃咳之状，咳而呕，呕则长虫出。忧伤肺者，咳而喘
息有声，甚则唾血，名为肺咳；不已，则大肠受之，大肠咳状，咳而遗失。恐伤肾者，咳而
腰背相引痛，甚则咳涎，名为肾咳；不已，则膀胱受之，膀胱咳状，咳而遗溺，久咳不已，
则三焦受之。三焦咳状，咳而腹满不欲食。此等皆聚于胃，关于肺。肺取 俞最近，故内因
多先有所感，世人并名肺咳嗽也，并属内所因。诊其脉，随其部位，与气口相应，浮紧则虚
寒，沉数则实热，弦涩则少血，洪滑则多痰。以此类推，无施不可。
人之所以能够滋养身体，依靠的唯有气与血。呼吸均匀平稳，是卫气（运行于体表、具有防御和温煦作用的气）的正常状态，若失常则导致咳嗽；津液流动滋润，是营血（行于脉中、具有营养作用的血）的正常状态，若失常则产生痰涎。出现咳嗽并吐出痰涎，说明气血已经紊乱。
然而世间治疗咳嗽的药物极多，却最终不能普遍奏效，大概是因为致病的病因各不相同。世人所说的“五嗽”，虽然是从五脏的角度来论述，但本质上，内因七情（喜、怒、忧、思、悲、恐、惊），外合六淫（风、寒、暑、湿、燥、火），以及饮食起居不当、房劳过度或大声呼喊，都能单独或复合地引发疾病。所以《黄帝内经》说：五脏六腑，感受寒热风湿等邪气，都会使人咳嗽。又有轻微受寒引起轻微咳嗽，被厉风所吹导致声音嘶哑并发咳；热邪在上焦，咳嗽发展为肺痿（肺部组织萎弱不用的病证）；秋季受伤于湿邪，冬季发生咳嗽，这些都属于外因。喜悦使气机涣散，愤怒使气机激逆，忧愁使气机郁结，思虑使气机阻滞，悲伤使气机收敛紧绷，恐惧使气机下陷，惊骇使气机紊乱，这些都能引发咳嗽，即属于内因。至于饮食生冷、房劳作役导致的咳嗽尤为多见，这些都不属于内因或外因，称为不内外因。难道可以用一种方法去治疗吗？治疗时，应当推究其三种病因，根据脉象和证候进行治疗，采用发散、攻下、温补、催吐等方法，以恢复平衡为准则。
伤风引起的咳嗽，表现为憎恶寒冷且高热，自汗出且怕风，口干烦躁；伤寒引起的咳嗽，表现为憎恶寒冷且发热，无汗且怕冷，烦躁但不口渴；伤暑引起的咳嗽，表现为烦热想喝水，口干燥，或者呕吐涎沫，声音嘶哑甚至咯血；伤湿引起的咳嗽，表现为骨节烦痛，四肢沉重，感觉洒淅恶寒，这些都属于外因。诊察其脉象，浮脉主风，紧脉主寒，数脉主热，细脉主湿。根据病变部位，与人迎穴（颈部动脉，用于判断阳经病变）的脉动相应；推究涉及的脏腑，就能发现疾病的根源。
喜悦过度损伤心脏，咳嗽且喉咙中间感觉像肿胀一样不适，严重时咽喉肿痛闭塞，名为心咳；若不止，则病传至小肠，小肠咳的症状是咳嗽时伴有失气（放屁）。愤怒过度损伤肝脏，咳嗽且两侧胁下疼痛，严重时身体不能转动，转动则两侧胁下胀满，名为肝咳；若不止，则病传至胆，胆咳的症状是咳嗽并呕吐胆汁。思虑过度损伤脾脏，咳嗽且右胁下疼痛，隐隐牵引肩背，严重时不能活动，名为脾咳；若不止，则病传至胃，胃咳的症状是咳嗽并呕吐，呕吐时可能有蛔虫排出。忧愁过度损伤肺脏，咳嗽且喘息有声，严重时唾血，名为肺咳；若不止，则病传至大肠，大肠咳的症状是咳嗽时大小便失禁。恐惧过度损伤肾脏，咳嗽且腰背相互牵引疼痛，严重时咳嗽吐涎沫，名为肾咳；若不止，则病传至膀胱，膀胱咳的症状是咳嗽时遗尿。久咳不愈，则病传至三焦（人体上、中、下三个部位的总称）。三焦咳的症状是咳嗽且腹部胀满不想进食。这些病症都聚集在胃，关联于肺。因为肺的俞穴（背部足太阳膀胱经上的穴位，用于治疗肺系疾病）距离最近，所以内因致病大多先有所感触，世人统称为肺咳嗽，这些都属于内因。诊察其脉象，根据病变部位，与气口（手腕桡动脉处，用于判断阴经及内脏病变）的脉动相应，浮紧脉表示虚寒，沉数脉表示实热，弦涩脉表示血少，洪滑脉表示痰多。以此类推，没有不可施治的情况。
What nourishes the human body is solely Qi and Blood. Regular respiration, with a steady interval between breaths, is the normal state of Wei Qi (Defensive Qi); when this state is disrupted, it leads to cough; the flowing and moistening of body fluids is the normal state of Ying Blood (Nutritive Blood); when disrupted, it produces phlegm and saliva. Coughing accompanied by expectoration indicates that Qi and Blood have already become disordered.
Although there are numerous medicines in the world for treating cough, they ultimately cannot be universally effective, largely because the causes of disease vary. The so-called "Five Coughs" discussed by people are described from the perspective of the Five Zang Organs. However, essentially, internal factors such as the Seven Emotions (Joy, Anger, Worry, Pensiveness, Sorrow, Fear, Fright), external factors such as the Six Excesses (Wind, Cold, Summer-heat, Dampness, Dryness, Fire), improper diet and daily life, excessive sexual activity, or loud shouting, can all cause disease either singly or in combination. Therefore, the *Classic* states: "The Five Zang and Six Fu organs, upon contracting cold, heat, wind, or dampness, all cause cough." Additionally, slight cold induces slight cough; being blown by fierce wind causes hoarseness and cough; heat in the Upper Jiao (Upper Burner) leads to Lung Wei (Lung Atrophy/Withering); injury by dampness in autumn and cough in winter are all external causes. Joy scatters Qi, anger agitates Qi, worry gathers Qi, pensiveness knots Qi, sorrow tightens Qi, fear sinks Qi, and fright disorders Qi; all these can induce cough, constituting internal causes. As for cough caused by consuming raw/cold foods or overexertion due to sexual activity or labor, these are particularly common and belong to neither internal nor external causes, termed "neither internal nor external causes." Can one single method treat them? Treatment must deduce the Three Causes, and based on pulse and syndrome differentiation, employ methods such as dispersing, purging, warming, or inducing vomiting, aiming to restore balance.
Cough due to Wind Injury presents with aversion to cold and high fever, spontaneous sweating, aversion to wind, dry mouth, and irritability; Cough due to Cold Injury presents with aversion to cold and fever, absence of sweating, aversion to cold, irritability, but no thirst; Cough due to Summer-heat Injury presents with vexatious heat and desire for drinking, dry mouth, possibly vomiting saliva, hoarseness, or hemoptysis; Cough due to Dampness Injury presents with painful joints, heavy limbs, and a sensation of chilliness (shivering). These all belong to external causes. Upon examining the pulse, floating indicates Wind, tight indicates Cold, rapid indicates Heat, and fine indicates Dampness. Corresponding to the Renying acupoint (Renying, ST9, used to assess Yang meridians) based on the location of the pathology; and by deducing the involved Zang-Fu organs, the source of the disease can be identified.
Excessive Joy damages the Heart, causing cough with a sensation of swelling in the throat, and severely, sore throat and throat obstruction; this is named Heart Cough. If unresolved, it transmits to the Small Intestine; Small Intestine Cough presents with cough accompanied by flatus. Excessive Anger damages the Liver, causing cough with pain under both hypochondria, and severely, inability to turn the body, turning causes fullness under both hypochondria; this is named Liver Cough. If unresolved, it transmits to the Gallbladder; Gallbladder Cough presents with cough and vomiting of bile. Excessive Pensiveness damages the Spleen, causing cough with pain under the right hypochondrium, radiating faintly to the shoulder and back, and severely, inability to move; this is named Spleen Cough. If unresolved, it transmits to the Stomach; Stomach Cough presents with cough and vomiting, where roundworms may be expelled. Excessive Worry damages the Lungs, causing cough with wheezing and audible breathing sounds, and severely, spitting blood; this is named Lung Cough. If unresolved, it transmits to the Large Intestine; Large Intestine Cough presents with cough accompanied by loss of stool and urine. Excessive Fear damages the Kidneys, causing cough with pulling pain between the waist and back, and severely, coughing up saliva; this is named Kidney Cough. If unresolved, it transmits to the Bladder; Bladder Cough presents with cough accompanied by urinary incontinence. Chronic cough that does not resolve transmits to the Sanjiao (Triple Burner). Sanjiao Cough presents with cough, abdominal fullness, and lack of appetite. All these conditions gather in the Stomach and relate to the Lungs. Since the Shu points of the Lungs (Back-Shu points of the Lung) are closest, internal causes often involve prior sensory/emotional impact, which people generally name as Lung Cough; these all belong to internal causes. Upon examining the pulse, corresponding to the Qikou acupoint (Radial artery at the wrist, used to assess Yin meridians and Zang organs) based on location, floating and tight indicates deficiency-cold, deep and rapid indicates excess-heat, wiry and choppy indicates blood deficiency, and surging and slippery indicates excess phlegm. By analogy, no treatment is impossible.