Tongue diagnosis is an important method for diagnosing diseases in traditional Chinese medicine. The tongue is connected to the five internal organs through meridians. Therefore, the deficiency and excess of the human body's internal organs, qi, blood, and body fluids, as well as the changes in the severity of the disease, may be objectively reflected in the tongue. Through tongue diagnosis, we can understand the deficiency and excess of the internal organs and the nature, severity, and relationship of the disease pathogens. change. Among them, changes in tongue quality mainly reflect the deficiency and excess of the internal organs and the rise and fall of Qi and blood; while changes in tongue coating are mainly used to judge the depth and severity of external evils, as well as the rise and fall of stomach Qi.

Traditional Chinese medicine divides the tongue into the tip, middle, base and sides of the tongue. It is believed that the tip of the tongue belongs to the heart and lungs, the middle of the tongue belongs to the spleen and stomach, the base of the tongue belongs to the kidneys, and both sides of the tongue belong to the liver and gallbladder (see Figure 3-1). The different parts of the tongue reflecting different organ lesions have certain clinical reference value, but they cannot be viewed mechanically and need to be considered comprehensively with other symptoms and signs.

1. Tongue quality: refers to the body of the tongue, mainly observing its color, shape and state.

The normal tongue is light red in color, reserved and moist, moderately fat, thin, old and tender, and can move freely and freely, indicating sufficient qi and blood. It can be seen in healthy people, but can also be seen in those who are experiencing the first onset of external infection or mild internal injuries.

(1) Tongue color

① Pale tongue: The tongue color is lighter than normal, mainly due to deficiency syndrome and cold syndrome. It is more common in blood deficiency, which is caused by weak Yang Qi and insufficient Qi and blood. elephant. If it is light in color but fat and tender, it is a sign of deficiency and cold; if it is fat and tender but has tooth marks on the edge, it is a sign of qi and yang deficiency.

②Red tongue: The tongue color is darker than normal and bright red, mainly due to heat syndrome, mostly internal heat syndrome. A red tip of the tongue indicates inflammation of the heart-fire; a red edge of the tongue indicates heat in the liver and gallbladder; red and dry tongue indicates heat damaging body fluids or yin deficiency and excessive fire.

③Red tongue: The tongue is dark red in color and indicates excess heat, mostly caused by evil heat that penetrates deep into the nutrients, blood or yin deficiency and excess fire.

The darker the red and crimson tongue, the more serious the heat evil.

④Ecchymotic tongue: There are blue-purple petechiae or spots on the tongue, mostly due to the accumulation of blood stasis.

⑤Bluish tongue: The whole tongue is blue and purple, either due to extreme heat or cold syndrome. If the tongue is deep purple and dry, it is extreme heat. In patients with warm heat, the disease is due to the introduction of nutrients and blood; if the tongue is light yellow-purple or blue-purple and smooth, it is a yin-cold syndrome.

(2) Tongue shape: Observe the tenderness, fatness, thorns, cracks, etc. of the tongue.

① Lao Nen: "Lao" refers to the texture of the tongue is rough, the shape and color are firm, mostly due to syndrome and heat syndrome: "Ten" refers to the texture of the tongue is fine, the texture is floating and tender, mostly due to deficiency syndrome syndrome or deficiency-cold syndrome.

② Fat and thin: "Fat" refers to the tongue being fat and swollen, which is mostly related to the retention of water and moisture. A pale and fat tongue with tooth marks on the edges of the tongue is mostly due to spleen deficiency or kidney yang deficiency and water-dampness retention; a red and swollen tongue is mostly due to internal dampness and heat or excessive heat and toxins. "Skinny" refers to a small and thin tongue, which is mostly due to deficiency syndrome. A person with a pale tongue and a thin tongue shape is mostly due to insufficient Qi and blood; a red tongue with a thin tongue shape is mostly due to yin deficiency and internal heat.

③ Thorny thorns: The tongue papilla is hyperplasia, hypertrophy, protrusions like thorns, mostly caused by excessive heat evil. The more severe the heat evil, the larger and more numerous the thorns will be. Clinically, thorns are more common on the tip and sides of the tongue. The thorns on the tip of the tongue are mostly caused by liver and gallbladder heat.

④Cracks: There are various longitudinal or transverse cracks or wrinkles on the tongue, which are mostly formed due to mucosal atrophy. Cracked tongue can be seen in a small number of normal people. Those with red tongues and cracks are mostly due to excessive heat; those with pale tongues and cracks are mostly due to deficiency of Qi and Yin.

(3) Tongue status: Observe whether the tongue body is trembling, crooked, soft, stiff, etc.

① Tremor: The tongue trembles involuntarily, mostly due to deficiency of qi and blood or internal movement of liver wind.

② Deviation: The tongue body is tilted to one side, which is mostly a sign of hemiplegia or stroke precursor.

③Atrophy: The tongue is unable to extend and curl, mostly caused by deficiency of Qi and blood and lack of nourishment of muscles and arteries.

④Toughness: The tongue is not soft, has difficulty in flexion and extension, or even cannot rotate. It is usually due to high fever and body fluid damage, excessive evil heat, or a sign of stroke.

2. Tongue coating: Tongue coating is the manifestation of stomach anger. Zhang Xugu said: "Tongue coating appears from the anger in the stomach, and stomach qi originates from the heart and spleen. Therefore, people who are not sick often have thin coating. This is the qi in the stomach, which is like a micro grass on the ground, like a barren land. , then the soil will be lifeless.” Wu Kun'an said: "The tongue is coated, just like the earth is coated.

The coating on the ground grows when moisture rises; the coating on the tongue grows when the stomach steams and the spleen becomes damp, so it is called coating. "Modern doctors believe that the formation of tongue coating is mainly due to the differentiation of filiform papillae. The ends of filiform papillae differentiate into keratinized trees. The gaps in the branches of keratinized trees are often filled with shed keratinized epithelium, saliva, bacteria, Food debris and exuded white blood cells form a normal tongue coating. The normal tongue coating is a thin layer of white, which is tender but not thick, moderately dry and moist, not slippery and not dry. Observe the color, thickness and content of the tongue coating. Moisturizing and drying.

(1) Coating color: white coating, yellow coating, gray coating, black coating, etc.

① White coating is the most common clinically, and others are the most common. Colored coating can be considered to be caused by the transformation of white coating. White coating generally belongs to the lung, mainly superficial syndrome and cold syndrome, but clinically, white coating can also be seen with internal syndrome and heat syndrome, such as thin, white and moist coating, which is caused by wind and cold. ; Thin, white and dry is wind-heat; white and thick greasy coating can be seen in cases of cold and dampness.

② Yellow coating can be different from light yellow, tender yellow, dark yellow, burnt yellow, etc. Generally speaking, yellow coating is different. The darker the color, the more serious the heat evil. Light yellow means mild heat; light yellow means more severe heat; dark yellow means heat knot; yellow and dry means heat damages the body; yellow and greasy means damp heat.

③ Gray and black coating are mostly caused by heat syndrome, and there are also symptoms of cold-dampness or deficiency and cold. The tongue coating is gray and black and dry, which is caused by excessive heat and dampness. The gray and black coating is mostly caused by Yang deficiency and cold syndrome. The more serious stage of the disease

(2) Thickness: thin coating, thick coating, little coating, no coating