1 Yin syndrome and yang syndrome
Syndrome differentiation of yin and yang, based on the application of the conception that all things can be divided into two aspects known as yin and yang, generalizes diseases into two categories, i.e. yin syndrome and yang syndrome. External, heat and sthenia syndromes are of yang category; while internal, cold and asthenia syndromes are of yin category. Therefore, yin and yang are the leading ones in the eight principles and include the other six ones.
2.1.4.1.1 Yin syndrome
Syndromes that correspond to the nature of “yin” are called yin syndromes. Internal syndrome, cold syndrome and asthenia syndrome are of yin category. However, yin syndrome usually refers to asthenia cold syndrome.
Clinical manifestations: Yin syndrome varies with different diseases. The usual symptoms are dull complexion, dispiritedness, fatigue, cold limbs, low voice, shortness of breath, bland taste in the mouth without thirst, clear and profuse urine, loose stool, pale and tender tongue, sunken and thin pulse, or sunken, slow and weak pulse, etc.
Analysis of symptoms: Yin signifies quietness and cold. Dispiritedness, fatigue, low voice and shortness of breath are signs of hypofunction of viscera; dull complexion, cold limbs, bland taste in the mouth without thirst, clear and profuse urine and loose stool are signs of insufficiency of yangqi and internal exuberance of yin cold; pale and tender tongue, sunken and thin pulse or sunken, slow and weak pulse are signs of asthenic cold syndrome.
2.1.4.1.2 Yang syndrome
The syndromes that correspond to the nature of “yang” are of yang category. External syndrome, heat syndrome and sthenia syndrome are of yang category.However, usually yang syndrome refers to sthenic heat syndrome.
Clinical manifestations:Yang syndromes in diseases vary in manifestations. The usual symptoms are flushed complexion, fever with preference for cold, restlessness, high voice, hoarse breath, dyspnea with sputum rale, dry mouth with thirst and desire to drink, scanty brownish urine, retention of dry feces, deep reddish tongue with yellow and dry fur, powerful or full or slippery pulse, etc.
Analysis of symptoms: Yang governs movement and heat. Flushed complexion, fever with preference for cold, restlessness and high voice are signs of hyperfunction of the viscera; hoarse breath, dyspnea with sputum rale are the signs of retention of phlegm in the lung and failure of the lung to disperse and descend; dry mouth with thirst and desire to drink, scanty and brownish urine and retention of dry feces are signs of exuberant heat impairing body fluid; deep reddish tongue with yellow and dry fur and powerful or full or slippery pulse are signs of sthenic heat syndrome.
