2 Inquiry of sweating
Sweating is transformed from body fluid by yangqi and excretes from the sweat pores. Normally sweat functions to regulate yingqi and weiqi and moisten the skin.
Under pathological conditions, sweating becomes abnormal due to the invasion of pathogenic factors and imbalance between yin and yang inside the body. Inquiry Of
sweating can enable one to understand the nature of the pathogenic factors and the conditions of yin and yang inside the body. Inquiry of sweating includes hidrosis and anhidrosis as well as time, region and quantity of sweating.
1.3.3.2.1 Anhidrosis
Anhidrosis when there should be sweating is usually caused by exogenous cold or insufficiency of yin blood and body fluid or asthenia of yangqi.
Anhidrosis in external syndrome: This condition is often seen in external sthenia syndrome due to exogenous cold. Since cold tends to stagnate and contract, the muscular interstices become tense and the sweat pores are closed up, preventing sweating from excreting. The usual symptoms are serious aversion to cold, mild fever and floating and tense pulse, etc.
Anhidrosis in internal syndrome: This condition is usually seen in blood asthenia syndrome and yang asthenia syndrome due to insufficiency of body fluid. If it is accompanied by such symptoms like dry skin, dry mouth, dry feces, it is usually caused by depletion of body fluid due to exhaustion of the sweat source; if it is accompanied by pale complexion and lips, whitish pale tongue, it is usually caused by insufficiency of yin blood and exhaustion of sweat source; if it is accompanied by aversion to cold and cold limbs, it is usually caused by insufficiency of yangqi and hypofunction to transform qi.
1.3.3.2.2 Hidrosis
Sweating can be caused by exogenous cold attack, or wind-heat invading the superficies, or exuberance of endogenous heat, or endogenous heat due to yin asthenia, or weakness of weiqi due to qi asthenia, or excretion of body fluid due to sudden loss of yangqi.
Hidrosis in external syndrome: This condition is usually seen in external asthenia syndrome due to exogenous wind attack, or external heat syndrome due to exogenous wind-heat and diseases due to weakness of weiqi complicated by exogenous wind attack. Wind tends to open and leak, while heat tends to rise and disperse.
Attacked by wind and heat, the muscular interstices become loose and sweat excretes. Sweat tends to excrete if weiqi is weak and the muscular interstices are loose. If accompanied by fever, aversion to wind and floating and slow pulse, it is external asthenia syndrome; if accompanied by high fever, light aversion to cold, sore-throat and floating and rapid pulse, it is external heat syndrome.
Hidrosis in internal syndrome: This condition is usually seen in exuberance of endogenous heat syndrome, endogenous heat syndrome due to yin asthenia, weakness of weiqi due to qi asthenia and sudden loss of yangqi.
Spontaneous sweating: Spontaneous sweating refers to constant sweating, especially after physical movement, often seen in qi asthenia syndrome and yang asthenia syndrome. Since asthenia of yangqi fails to protect the superficies, the sweat pores will become loose and body fluid will excrete. That is why sweat is constant. Since physical movement further consumes yangqi, sweating becomes
more serious.
Night sweating: Night sweating refers to sweating occurring when the patient falls asleep but stopping after the patient wakes up. It is usually seen in endogenous heat syndrome due to yin asthenia, or asthenia syndrome of both qi and yin. It is caused by endogenous heat due to yin asthenia. When people fall asleep, yangqi enters into the body, the muscular interstices become loose and asthenic heat steams the body fluid to excrete. That is why sweating occurs during sleep. After people wake up, yangqi returns to the superficies, the muscular interstices become tense. Under this condition, endogenous heat with Yin asthenia cannot steam the body fluid to excrete. That is why sweating stops after people wake up. Asthenia of both qi and yin usually lead to both spontaneous sweating and night sweating.
Profuse sweating: Profuse sweating is either asthenic or sthenic. Profuse sweating with high fever, flushed complexion, thirst, preference for cold drinks and full large pulse is seen in sthenic heat syndrome due to exuberance of endogenous heat which drives body fluid to excrete, If profuse sweat occurs in patients with prolonged illness accompanied by symptoms like pale complexion, cold limbs and indistinct pulse, it is yang exhaustion syndrome due to sudden loss of yang which leads body fluid to excrete.
Sweating following shivering: Sweating following shivering is usually seen during the course of exogenous febrile disease, marking the turning point of conflict between healthy qi and pathogenic factors and the development of pathological conditions. If fever abates, pulse calms down and the body turns cool after sweating, it is a sign that pathogenic factors are being expelled; if there are restlessness and rapid pulse after sweating, it is a critical sign of domination of pathogenic factors and decline of healthy qi.
Head sweating: Head sweating means that sweat only appears over the head. The causes of head sweating are various, including exuberant heat in the upper energizer which drives body fluid to excrete in the upper, often accompanied by reddish complexion and thirst; accumulation of damp heat in the middle energizer, in which the stagnation of dampness and steaming of heat drive the body fluid to excrete in the upper, often accompanied by abdominal fullness, heaviness of the head and body; prolonged and serious disease with primordial qi on the verge to exhaust in which asthenic yang floats upward and the body fluid excretes in the upper together with yang, often accompanied by pale complexion and cold limbs. Besides, exuberance of yangqi due to extravagant intake of pungent food or hot soup and drinking of wine may drive heat to steam in the upper and lead to head sweating. But head sweating in this case is not pathological.
Hemihidrosis: Hemihidrosis means sweating appears over half of the body, either the upper or the lower, the left side or the right side. The location of disease is on the part of the body without sweat. This problem is usually seen in apoplexy, flaccidity and hemiplegia, often caused by wind phlegm or stagnant phlegm and obstruction of the meridians by wind dampness which prevent weiqi and yingqi from flowing as well as qi from normal circulation.
Sweating over palms and soles: If it is accompanied by dry mouth and throat, restless feverish sensation over the palms, soles and chest as well as thin and rapid pulse, it is usually caused by steaming of stagnant heat in the yin meridians; if it is accompanied by restless thirst, preference for cold drinks, brownish urine, constipation and full and rapid pulse, it is usually caused by exuberant heat in the yangming meridian; if it is accompanied by heaviness of the head and body, dull fever and yellowish greasy fur, it is usually caused by steaming of damp heat in the middle energizer.
Chest sweating: Chest sweating is usually of asthenia syndrome. If it is accompanied by lassitude, anorexia, palpitation and insomnia, it is usually caused by simultaneous asthenia of the heart and spleen; if it is accompanied by palpitation, dysphoria, insomnia, dreaminess and aching waist and knees, it is usually due to imbalance between the heart and the kidney.
Besides, it is also necessary to know the temperature and colour of sweating. Generally speaking, cold sweating is due to decline of yangqi, while feverish sweating is due to exogenous wind heat or steaming of endogenous heat. Yellowish sweating is often due to interaction of wind, dampness and heat.
