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TCM Book Club Issue 2906
Daily updates to accompany the growth of TCM practitioners
IIntroduction: It is generally believed that tongue coating can objectively reflect the condition of a disease. However, during the course of disease progression, due to individual differences in constitution, tongue coating may present illusions that do not align with the underlying condition. Some patients experience changes in tongue coating after receiving various treatments, which can affect the diagnostic observations in TCM. Therefore, in clinical practice, tongue diagnosis should adhere to the principle of knowing the constants while recognizing the changes, and diagnosis must integrate the four examinations for a comprehensive analysis, avoiding being misled by illusions. (Editor/Tang Yichao)
Tongue Diagnosis Must Adhere to Constants While Recognizing Changes Author/Mou Zhonglin It is generally believed that tongue coating can objectively reflect the condition of a disease. However, during the course of disease progression, due to individual differences in constitution, tongue coating may present illusions that do not align with the underlying condition. Some patients experience changes in tongue coating after receiving various treatments, which can affect the diagnostic observations in TCM. Therefore, in clinical practice, tongue diagnosis should adhere to the principle of knowing the constants while recognizing the changes, and diagnosis must integrate the four examinations for a comprehensive analysis, avoiding being misled by illusions. Here are three clinical cases for illustration.1. Case of Red Tongue with Glossy Coating Indicating Yang Deficiency Wang, female, 62 years old. Dizziness and lightheadedness, varying in intensity for 5 years. Western diagnosis: hypertension, arteriosclerosis. In the past half month, dizziness has worsened, unsteady gait, insomnia, blurred vision, red tongue with glossy coating like a mirror, pulse wiry and large. Initially treated with nourishing yin and lowering fire, calming the liver and subduing yang, using modified Zhen Gan Xi Feng Decoction, but dizziness persisted, appetite decreased significantly, and switching to Western medicine caused nausea and vomiting. Upon careful examination, the pulse was large and without root, dizziness worsened with exertion, thirst with preference for warm drinks, a long-standing preference for ginger soup, lower back soreness, cold feet, and clear urination. The diagnosis indicated insufficient life fire and spleen deficiency. A modified formula was prescribed: Yi Yi Ren (Coix Seed), Dan Pi (Moutan Cortex), Rou Gui (Cinnamon), Huai Shan (Chinese Yam), Dang Shen (Codonopsis), Gan Jiang (Dried Ginger), Ze Xie (Alisma), Long Gu (Dragon Bone), Mu Li (Oyster Shell), and Zhi Gan Cao (Honey-Fried Licorice). Initially concerned about excessive warmth, a light dose was prescribed, and after taking it, the dizziness decreased while appetite improved. The formula was adjusted by removing Long Gu and Mu Li, adding Fu Zi (Aconite) and Shu Di Huang (Rehmannia), gradually increasing the dosage. After taking over ten doses, all symptoms resolved, and blood pressure returned to normal. The following year, while visiting relatives in another city, fatigue from travel caused dizziness to recur. The local hospital prescribed Chinese medicine, which was not suitable; upon re-examination, the original formula was presented, and the physician believed that with such a tongue appearance, a large dose of warming herbs seemed inappropriate. The patient insisted on the original formula and achieved efficacy. Note: A red tongue indicates heat, and a glossy coating suggests yin deficiency, which is its norm. According to “Tongue Diagnosis and Differentiation”: “A bright red color, without coating or spots, shiny like a mirror… indicates extreme yin deficiency due to water depletion and fire inflammation. In this case, it initially appeared to resemble yin deficiency with yang excess, but was actually due to spleen and kidney yang deficiency. “Shang Han Lun” states: “Tongue coating arises from the qi of the stomach,” if the middle earth lacks the qi to generate, the coating becomes glossy and peeled like a mirror, kidney yang is weak, yin and yang are not mutually supportive, and the rising fire causes the virtual yang to float above, thus the tongue is red with little moisture. Nourishing yin and subduing yang formulas can harm stomach qi and further suppress residual yang. As one ages, yang deficiency is common, hence the use of warming tonics to return fire to its source and strengthen spleen yang proved effective. It is said: “The authenticity of the syndrome is determined by the pulse, and the authenticity of the pulse is determined by the tongue.” However, the tongue also has its authenticity; one must carefully examine the symptoms, learn from past failures, and clarify the root of the disease. A red tongue with a peeled coating can indicate both deficiency and excess syndromes. Deficiency syndromes are often seen in yin deficiency, but yang deficiency can also present. Excess syndromes are mostly heat-related, but cold dampness can also be present. I have treated patients with stomach pain and diarrhea, where the tongue was red with a peeled coating; slightly administering a yin-nourishing flavor caused qi stagnation. Each time, I used formulas to regulate the stomach and tonify the middle, achieving efficacy. In clinical practice, flexibility is crucial; one must think divergently and not rigidly adhere to tongue coating, lest misdiagnosis occurs.2. Case of Pale Tongue with Thick Greasy Coating Indicating Yin Deficiency Cold Shi, female, 65 years old. Poor appetite, afternoon fever for over ten days without resolution. Thirst without desire to drink, constipation, frequent urination with small volume, prefers to sleep with clothes and blankets, has slight sweating, pale tongue with thick greasy white coating mixed with gray-yellow, pulse wiry and rapid. Initially diagnosed as an upper respiratory infection, Western medicine was ineffective. At the height of summer, treated for summer dampness, using Huo Xiang Zheng Qi San and San Ren Tang, which resulted in abdominal distension. Believing the condition had worsened, I prescribed Da Yuan Yin and adjusted the stomach, but to no avail. Due to fatigue and weakness, I attempted to strengthen the middle and move the spleen, but it was also ineffective. In the last three days, left lower back and leg pain appeared, radiating to the left abdomen, making it difficult to turn, and appetite worsened, leaving me at a loss for a good strategy. Her husband, knowledgeable in medicine, mentioned a similar episode in the past that responded well to yin-nourishing herbs. Now, with increasing fatigue, I tried 3 grams of Xi Yang Shen (American Ginseng) for adjustment. The next day, she reported slight improvement in spirit and reduced back pain; from then on, I realized the treatment should focus on nourishing yin. After repeated consideration, I prescribed: Bei Sha Shen (North American Ginseng), Sheng Bai Shao (White Peony), Gou Qi Zi (Goji Berries), Nu Zhen Zi (Ligustrum), Huo Ma Ren (Hemp Seed), Sheng Di Huang (Raw Rehmannia) each 10g, Mai Dong (Ophiopogon) 8g, Di Gu Pi (Lycium Bark) 15g, Yi Yi Ren (Coix Seed) and Huai Niu Xi (Achyranthes) each 6g. After about a week of treatment, bowel movements improved, fever subsided, and appetite increased, with all symptoms resolved. Subsequently, symptoms rarely recurred, and the original formula was effective whenever needed. Note: In this case, the initial observation of the tongue coating suggested a failure of the middle earth to function, with dampness obstructing and stagnating, leading to heat formation. The use of formulas to eliminate dampness and transform turbidity was ineffective, but later nourishing yin proved successful. Without yin, yang cannot function; insufficient yin fluid means no water to navigate the boat; if the stomach fails to descend, the middle yang is constrained, and turbidity cannot descend, leading to a thick greasy tongue coating. The repeated use of warming and drying formulas harmed the nourishing yin, resulting in the meridians being deprived of nourishment, causing back and leg pain. However, with such a tongue appearance, initial use of yin-nourishing methods seemed hesitant. After much contemplation, recalling a similar past episode that responded well to yin-nourishing treatment, I initially tried a diagnostic treatment that gained support. It is said: “New diseases are diagnosed from the coating, while chronic diseases are diagnosed from the pulse.” In this case, treatment based on the coating did not yield results for a long time, and the pulse was wiry and rapid, but weak upon palpation. “Zheng Zhi Hui Bu” states: “A wiry pulse without strength indicates yin deficiency, and if severe, the pulse is rapid.” The mutual reference confirmed the signs of yin deficiency, and I dared not be rigid in treating greasy coating as dampness, boldly nourishing yin, thus achieving complete success.3. Case of Thick Black Coating Indicating Damp-Heat Wang, male, 40 years old. Thick black tongue coating for over ten days. The patient had a right inguinal abscess a week ago, accompanied by fever. After incision and drainage, he was treated with antibiotics, hormones, and Chinese medicine to clear heat and detoxify, resulting in fever resolution, but appetite significantly decreased, and black coating increased, covering the entire tongue. Repeated use of clearing and warming methods resulted in increased black coating. The patient appeared pale and slightly swollen, with a bitter and sticky mouth, coughing up clear, thin phlegm, and loose stools. The tongue was red with thick black coating like thick ink, which did not diminish upon wiping, and the pulse was wiry, small, and slippery. He had a long-standing preference for smoking and drinking, with a history of chronic cholecystitis for 5 years. The diagnosis indicated insufficient middle yang, dampness obstructing, and prolonged stagnation leading to heat formation. Prescribed were Rou Gui (Cinnamon) 4g, Wu Yao (Evodia) 5g, Xiang Lian Wan (Xiang Lian Pill) (swallowed), Long Dan Cao (Gentian) and Huang Bai (Phellodendron) each 3g, Ze Xie (Alisma) and Huo Xiang (Agastache) each 6g, and Fu Ling (Poria) 12g. After three doses, the bitter mouth decreased, and stools became formed, with slight reduction in black coating. Recently, he felt wind-cold and experienced right flank pain. The previous formula was adjusted by removing Wu Yao and Huo Xiang, adding Yin Chen (Yin Chen Hao) 15g, Wu Mei (Mume) and Zhi Jun (Zhi Mu) and Hou Po (Magnolia Bark) each 4.5g. After 8 doses, the flank pain resolved, and the black coating diminished. A week later, due to dietary indiscretion, the black coating reappeared, and the previous formula was readjusted, adding Ban Xia (Pinellia) 6g and Cao Guo (Tsaoko) 3g. After 5 doses, the coating receded, and dietary precautions were advised, followed by a week of treatment to restore health. Three months later, follow-up showed no recurrence. Note: Thick black coating is generally believed to indicate either extreme heat or excessive cold (as seen in textbooks such as “Foundations of TCM”), but this is not always the case; comprehensive judgment must consider other manifestations. Thick black coating is often seen in phlegm-damp conditions. “Tongue Diagnosis Guide” states: “Thick black coating indicates diseases of the Taiyin Spleen Meridian. Phlegm-damp arises from metabolic disorders of water and liquid.” The transformation of water and liquid is governed by the spleen; if the earth fails to control water, it stagnates and becomes problematic. When it rises to the tongue, it appears as gray-black and slippery. It can be due to damp-heat or cold-dampness, both of which can be observed. The patient had a long-standing preference for smoking and drinking, leading to internal damp-heat, resulting in an abscess. Although the pus was drained, the damp-heat remained, and excessive use of cold and cool herbs harmed the middle yang, causing dampness to obstruct and stagnate, preventing clear qi from rising, leading to thick black coating on the tongue. The treatment combined cold and warmth, using pungent to open and bitter to drain. Rou Gui and Wu Yao uplifted the middle yang; Long Dan and Huang Bai cleared heat and dried dampness; supplemented with Huo Xiang, Fu Ling, and Ze Xie to promote the middle and eliminate dampness. After recovery, dietary precautions were advised to prevent recurrence.
Recommended Reading
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Pediatric Diagnosis: The Importance of Tongue and Coating
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Observing the Tongue: Avoiding Pitfalls
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Clearly All Spleen Deficiency with Dampness, Yet Three Tongue Appearances Yield Completely Different Conclusions?
I Copyright Statement
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This article is excerpted from “Liaoning Journal of Traditional Chinese Medicine”, Issue 5, 1983, Author/Mou Zhonglin. Edited by/Tang Yichao, Proofread by/Ma Xinting, Zhu Mingyang.
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