bubble_chart Concept

The tongue has no coating, is smooth and clean, and in severe cases, resembles a mirror surface, which is called "mirror tongue". It is also referred to as "smooth tongue", "glossy tongue", "peeled tongue", "red and tender tongue"

. A tongue without coating indicates a critical condition, and the diagnosis must be meticulous and accurate.

bubble_chart Pattern Analysis

1. Stomach Yin Deficiency︰The tongue is red (or deep red) and glossy, lacking moisture on the surface, especially in the center, accompanied by restlessness, thirst, and loss of appetite, or hunger without desire to eat, retching and hiccups, or epigastric pain, burning heat in the skin, low-grade fever, severe constipation, and even dysphagia or regurgitation, with a thready, rapid, and weak pulse. The tongue appears bright and dry, particularly in the center; it is often accompanied by dry mouth and lips, burning heat in the skin, and a thready, rapid, and weak pulse. The treatment should focus on nourishing stomach yin, and Stomach-Tonifying Decoction may be used, or Prepared Liquorice Decoction with ginger and cinnamon removed and fresh Dendrobium, sugarcane juice, and Ophiopogon Tuber added.
2. Exhaustion of Kidney Yin︰The tongue is deep red (or red) and glossy, with a dry and dull color, lacking moisture when touched, and the tongue body is thin and small. The throat is dry, the complexion is haggard, the body is emaciated, and there is dizziness and blurred vision. There may be a cicada-like buzzing in the ears, hearing impairment or deafness. The teeth appear as dry as withered bones, with loose teeth and hair loss. There is soreness and weakness in the lower back and knees, and weakness in both legs. There is vexing heat in the chest, palms, and soles, tidal fever with night sweats, and a deep, thin, and rapid pulse. The tongue color is dry and lacks luster. It is often accompanied by dry mouth, sore throat, low-grade fever with flushed cheeks, vexing heat in the chest, palms, and soles, tidal fever with night sweats, and a deep, thin, and rapid pulse. The stomach governs reception and prefers moisture over dryness, with descending as its harmonious function. Therefore, insufficiency or depletion of stomach yin inevitably affects its functions of reception and descending, manifesting as hunger without appetite, aversion to food, retching or hiccups, epigastric pain, or regurgitation. In cases of kidney yin deficiency, there is a failure of water to nourish fire, leading to frenetic stirring of ministerial fire. This is accompanied by dizziness and blurred vision, tinnitus or deafness, insomnia, seminal emission, a haggard complexion, weakness in both legs, loose teeth, and hair loss. The treatment should focus on nourishing kidney yin. Suitable formulas include the Ten-Ingredient Sweet and Cold Rescue and Tonify Decoction or Left-Restoring Decoction.
3. Deficiency of Both Qi and Yin︰The tongue is pale red, glossy, dry, and lacking moisture, or entirely devoid of body fluids, accompanied by listlessness, fatigue, lack of strength, shortage of qi, reluctance to speak, faint low voice, no hunger or appetite, restless sleep, thirst, dry throat, parched lips, sunken eyes, dry skin, or even withered appearance, with a weak or thin and rapid, feeble pulse. This is commonly seen in the late stage (third stage) of acute Rebing, or during certain chronic, consumptive diseases, where damage to yin and depletion of qi cause the tongue texture to lose the warmth and moisture of qi, resulting in a pale red and glossy appearance. Treatment should focus on tonifying qi and nourishing yin, often using Pulse-Reinforcing Powder.
4. Deficiency of Both Qi and Blood︰The tongue is pale white and smooth, often seen with a pallid or shallow yellow complexion, pale lips and nails, dizziness, palpitations, insomnia, fatigue, lack of strength, shortage of qi, reluctance to speak, faint low voice, numbness in hands and feet, poor appetite, loose stools, clear and copious urine, and a deep, thin, weak pulse. This condition is mostly caused by spleen and stomach injury, poor appetite, and the inability to generate qi and blood, leading to prolonged illness and deficiency of both qi and blood. The tongue texture is not nourished, the tongue coating gradually sheds, and new coating cannot regenerate, resulting in a pale white and smooth tongue. It is commonly seen in cases of excessive blood loss, spleen-stomach weakness, insufficient generation and transformation, or postpartum women. Although both syndromes exhibit clinical manifestations of qi deficiency, such as fatigue, lack of strength, shortage of qi, reluctance to speak, faint low voice, and a weak pulse, deficiency of both qi and yin also shows signs of body fluid depletion, including thirst, dry throat, parched lips, sunken eyes, dry skin, even withered appearance, scanty urine, and rapid pulse. Deficiency of both qi and blood, on the other hand, shows signs of blood deficiency, such as a shallow yellow or pallid complexion, palpitations, dizziness, pale lips and nails, and a thin pulse. Although body fluids and blood share the same origin, their deficiency symptoms are distinctly different and should be carefully distinguished in clinical practice. Treatment focuses on strengthening the spleen, nourishing the stomach, tonifying qi, and generating blood, using the Shiquan Ganwen Jiubu Decoction.

Whether it is internal damage or external contraction, if this tongue is observed, it often indicates the exhaustion of stomach and kidney yin fluids, with the tongue color mostly red or deep red; for those with yin deficiency and qi deficiency, the tongue is pale red and glossy; for those with both qi and blood deficiency, the tongue is pale white and glossy. The above are all critical conditions, and it is imperative to carefully examine the symptoms and differentiate the treatment, taking all necessary rescue measures to prepare for any eventuality.

bubble_chart Documentation

1. "Guide to Tongue Diagnosis: Differentiation of Tongue Examination and Syndrome Identification": "If there is suddenly a mirror-like patch in the middle of the tongue, without coating and deep red, this indicates a severe deficiency of body fluids in the spleen, stomach, and pericardium, leading to a lack of nourishment. There may also be static blood in the stomach, and this coating may appear in the absence of illness or after recovery. In such cases, it is appropriate to disperse and resolve stasis and accumulation, rather than hastily nourishing body fluids. ... If there is congealed phlegm in the pericardium or hidden cold in the life gate, a smooth, mirror-like patch may suddenly appear on the surface of the tongue."
2. Wenre Jingwei · Xue Sheng-bai's "Treatise on Dampness-Heat Diseases": "In the pattern of dampness and heat, after four or five days, there may be extreme thirst, chest tightness to the point of suffocation, incessant retching, a fine and rapid pulse, and a mirror-like tongue. This indicates that stomach fluids have been damaged and gallbladder fire is surging upward. It is advisable to use watermelon juice, gold juice, fresh unprocessed Rehmannia root juice, and sugarcane juice, and to grind and take Curcuma root, Aucklandia root, Cyperus, and Lindera, among other ingredients."