Eight Principles Diagnosis
The Eight Principles, namely Yin, Yang, Exterior, Interior, Cold, Heat, Deficiency, and Excess, form one of the theoretical foundations of TCM diagnosis and treatment. The Eight Principles diagnosis integrates data obtained from the four examinations based on the state of the body’s Zheng Qi (Vital Energy), the nature of the pathogenic factors, and the depth of the disease location, categorizing them into eight types of syndromes: Yin, Yang, Exterior, Interior, Cold, Heat, Deficiency, and Excess.
The content of the Eight Principles has been established in the “Huangdi Neijing” (Yellow Emperor’s Inner Canon). Zhang Zhongjing applied it more specifically in the treatment of febrile diseases and miscellaneous disorders. The “Jingyue Quanshu” contains sections such as “Yin and Yang” and “Six Transformations” that further elaborate on the Eight Principles.
The clinical manifestations of diseases are diverse and complex. From the perspective of Eight Principles diagnosis, any symptom can be categorized using Yin and Yang, the nature can be explained through Cold and Heat, the depth of the disease can be reflected through Exterior and Interior, and the strength of the pathogenic and righteous Qi can be described through Deficiency and Excess. The Eight Principles serve as a method for analyzing the common characteristics of diseases, acting as a general guideline for various diagnostic methods. In the process of diagnosing diseases, it simplifies complexity and highlights key points, applicable to the diagnosis across all clinical specialties. Specifically, the diagnosis in each specialty is deepened based on the Eight Principles diagnosis.
In the Eight Principles diagnosis, the relationships among the eight categories of syndromes—Yin and Yang, Cold and Heat, Exterior and Interior, Deficiency and Excess—are not parallel. Generally, Exterior syndromes, Heat syndromes, and Excess syndromes fall under the category of Yang syndromes, while Interior syndromes, Cold syndromes, and Deficiency syndromes belong to the Yin syndromes. Therefore, in the Eight Principles diagnosis, the Yin and Yang syndromes encompass the other six syndromes. Furthermore, the eight categories of syndromes are not mutually independent; they are intermingled and intersect, reflecting the complex clinical manifestations.
Under certain conditions, the location of the disease and the nature of Deficiency and Excess, Cold and Heat can undergo varying degrees of transformation, such as Exterior pathogens entering Interior, Interior pathogens emerging to Exterior, Cold syndromes transforming into Heat, Heat syndromes turning into Cold, transitioning from Excess to Deficiency, and Deficiency leading to Excess. When the disease progresses to a certain stage, some phenomena may appear that are contrary to the nature of the pathological changes, such as true Cold presenting as false Heat, true Heat presenting as false Cold, true Deficiency presenting as false Excess, and true Excess presenting as false Deficiency. Therefore, when conducting Eight Principles diagnosis, it is essential to be familiar with the characteristics of each syndrome while also paying attention to their interconnections.
Yin and Yang
Yin and Yang can summarize the entire condition of the disease and can also be used for the analysis of a single symptom. In the “Suwen: Discussion on Yin and Yang Correspondences,” it is stated: “Observe color and pulse, first distinguish Yin and Yang.” It also mentions, “Yang diseases are treated with Yin, and Yin diseases are treated with Yang.” Zhang Zhongjing classified febrile diseases into Yin and Yang syndromes, with three Yin and three Yang as the general principles. Ming dynasty physician Zhang Jingyue emphasized, “In diagnosing pulse and treatment, one must first examine Yin and Yang, which is the guiding principle of medicine.” This Yin and Yang is the overarching principle of Eight Principles diagnosis, which can govern the three pairs of principles: Exterior and Interior, Cold and Heat, Deficiency and Excess. Hence, the Eight Principles are sometimes referred to as “Two Principles and Six Essentials.” This highlights the significant position of Yin and Yang diagnosis in disease differentiation.
Yin Syndrome and Yang Syndrome
Any disease located in the Interior, in the blood, belonging to Cold, with insufficient Zheng Qi, and where the body’s response often shows signs of decline, falls under the category of Yin syndrome. Symptoms include mental fatigue, pale complexion, aversion to cold, cold limbs, shortness of breath, low voice, no thirst, loose stools, clear urine, pale tongue with white coating, and a deep, slow, weak pulse. The etiology and pathogenesis are due to aging, weakness, prolonged illness, or external pathogens invading the internal organs, leading to weakened Zheng Qi, Yang deficiency, and Yin excess.
Any disease located in the Exterior, in the Qi, belonging to Excess, and Heat, with intact Zheng Qi, and where the body’s response often shows signs of excess, falls under the category of Yang syndrome. Symptoms include irritability, red face, body heat, strong voice, thirst with a preference for cold drinks, coarse breathing, abdominal pain with a refusal to press, constipation, short red urine, red tongue with yellow coating, and a floating, rapid, or slippery pulse. The etiology and pathogenesis are due to the invasion of pathogenic Qi, where the pathogenic factor is strong and Zheng Qi is also strong, resulting from the struggle between Zheng and Xie.
Yin Deficiency and Yang Deficiency
Yin Deficiency and Yang Deficiency are syndromes arising from the deficiency of Yin and Yang in the body’s organs. Under normal physiological conditions, the Yin and Yang of the body must maintain a relative balance, as stated in the “Suwen: Discussion on the Vital Qi”—”When Yin is balanced, Yang is secreted, and the spirit is treated.” Once Yin and Yang lose this relative balance, changes in their excess and deficiency will occur, leading to disease.
Symptoms of Yin Deficiency include tidal fever, night sweats, heat in the palms and soles, weight loss, dry mouth and throat, short red urine, red tongue with little coating, and a thin, rapid, weak pulse. The etiology and pathogenesis are due to prolonged illness, or excessive sexual activity leading to deficiency of essence, blood, and body fluids, resulting in Yin not restraining Yang.
Symptoms of Yang Deficiency include fatigue, pale complexion, shortness of breath, aversion to cold, spontaneous sweating, pale tongue with white coating, and a weak pulse. The etiology and pathogenesis are due to prolonged illness, overexertion, or excessive sweating, vomiting, or diarrhea leading to severe Yang Qi deficiency, where Yang cannot restrain Yin.
Loss of Yin and Loss of Yang
Loss of Yin and Loss of Yang are often critical syndromes in the progression of diseases. Loss of Yin often occurs in cases of high fever, profuse sweating, severe vomiting and diarrhea, or excessive blood loss, leading to rapid loss of Yin fluids, commonly presenting with sticky sweat, shortness of breath, warm hands and feet, restlessness, thirst with a preference for cold drinks, flushed complexion, red and dry tongue, and a rapid, weak pulse. Loss of Yang often results from severe pathogenic heat or significant internal organ damage that depletes Yang Qi, and can also occur due to excessive sweating, vomiting, diarrhea, or blood loss, commonly presenting with cold sweat, pale complexion, weak breathing, aversion to cold, mental fatigue, pale and moist tongue, and a faint, weak pulse.
Exterior and Interior
Exterior and Interior are the two principles for distinguishing the depth and severity of disease. The concept of Exterior and Interior originally pertains to the structural organization of the body. In the “Huangdi Neijing,” the exterior refers to the skin, hair, and muscles; the interior refers to the internal organs. The “Suwen: Discussion on Cough” states: “The skin and hair are the exterior of the lungs; the exterior first receives the pathogenic Qi, and the pathogenic Qi enters through this connection.” This type of disease caused by the exterior receiving pathogens falls under the category of Exterior syndrome. The “Suwen: Discussion on the True Essentials” also proposes the treatment principle: “If it is in the skin, it should be treated with sweating.” This is the origin of the diagnosis and treatment of Exterior syndromes.
Generally, diseases affecting the skin, muscles, and meridians belong to Exterior syndromes and are relatively mild; diseases affecting the five internal organs, blood vessels, and bone marrow belong to Interior syndromes and are more severe.
Exterior Syndrome
Exterior syndrome refers to a type of syndrome caused by the invasion of the six excesses through the skin and mouth/nose, affecting the skin and meridian areas, characterized by rapid onset, short duration, and superficial location.
Clinical symptoms: include fever, aversion to wind and cold, body aches, headaches, thin white coating, and floating pulse, and may also include cough and nasal congestion.
Etiology and pathogenesis: The six excesses invade the skin and muscles, obstructing the Wei Qi’s dissemination, leading to heat; Yang cannot warm the skin, hence aversion to cold; the lungs govern the skin and open to the nose; when the skin and nose are affected by pathogens, lung Qi’s dissemination and descent are hindered, resulting in nasal congestion and cough; when the pathogenic Qi obstructs the meridians, Qi and blood flow is disrupted, leading to headaches and body aches; the struggle between Zheng and Xie at the exterior results in a floating pulse and thin white tongue coating.
Exterior syndrome can be classified into:
Exterior Cold: Wind-cold invasion, Zheng and Xie contending at the skin surface. Symptoms include significant aversion to cold, obvious headache and body aches, thin white coating, and floating tight pulse.
Exterior Heat: Wind-heat invading the lung Wei. Symptoms include mild aversion to cold, fever, red and painful throat, thin white-yellow coating, thirst, red tongue, and floating rapid pulse.
Exterior Deficiency: Wind invasion affecting the skin, with Wei Qi not solidified. Symptoms include significant aversion to wind, sweating, and floating weak pulse.
Exterior Excess: Wind-cold invasion, Zheng and Xie contending, with Wei Yang tightly securing the pores. Symptoms include significant aversion to cold, no sweating, headache, and floating tight pulse.
Interior Syndrome
Interior syndrome refers to a type of syndrome caused by external pathogens entering the interior, or directly affecting the interior, as well as internal injuries from emotions, diet, and overexertion, affecting the internal organs, Qi, blood, and bone marrow. Clinical manifestations are diverse, characterized by a longer duration and deeper location.
Clinical symptoms: include no aversion to wind and cold, pulse not floating, and often changes in tongue quality and coating.
Etiology and pathogenesis: Generally influenced by three factors: first, the development from Exterior syndrome, where the exterior pathogen enters the interior; second, the direct invasion of the exterior pathogen into the internal organs; third, internal injuries from emotions, diet, and overexertion leading to dysfunction of the internal organs.
Interior syndrome can be classified into:
Interior Cold: External cold entering the interior, or insufficient Yang Qi. Symptoms include aversion to cold, preference for warmth, cold limbs, no thirst, nausea, vomiting, abdominal pain with diarrhea, clear long urine, white slippery coating, and deep slow pulse.
Interior Heat: External pathogens entering the interior transforming into heat, or heat directly affecting the internal organs, or emotional disturbances transforming into fire. Symptoms include no aversion to cold, but aversion to heat, high fever, thirst, irritability, sweating, constipation, short red urine, yellow dry coating, and rapid pulse.
Interior Deficiency: Insufficient Yin and Yang Qi in the internal organs, leading to reduced function. Symptoms include fatigue, low voice, aversion to cold, spontaneous sweating, pale tongue, white coating, and weak pulse.
Interior Excess: External pathogens entering the interior, accumulating in the stomach and intestines, or caused by dysfunction of the internal organs. Symptoms include abdominal distension and pain, refusal to press, constipation, yellow red urine, and thick dry black coating, with a deep strong pulse.
Relationship Between Exterior and Interior Syndromes
Interior syndrome emerging from the exterior: This occurs when the body’s resistance increases, or when treatment and care are appropriate, allowing the pathogenic factor to emerge from the interior to the exterior, i.e., from interior to exterior. For example, when there is internal heat and irritability, cough, and chest tightness, followed by fever and sweating, irritability decreases, or rashes appear, this indicates the pathogenic factor has emerged from the interior to the exterior.
Exterior syndrome entering the interior: This occurs when the body’s resistance is low, or the pathogenic Qi is too strong, or treatment and care are inappropriate, leading to exterior syndrome entering the interior. For example, if there is fever and aversion to cold, but then there is no aversion to cold and aversion to heat, along with thirst, frequent drinking, red tongue, yellow coating, and red urine, this indicates the disease has transitioned from exterior to interior heat syndrome.
Simultaneous Exterior and Interior disease: This refers to the simultaneous appearance of exterior and interior syndromes at a certain period of the disease. Apart from the initial stage of the disease, where exterior and interior syndromes can coexist, this often occurs when the exterior syndrome has not resolved, and the interior is also involved; or when the exterior disease has not resolved, and another disease is involved, such as first an exterior pathogen, then dietary injury; or first an internal injury, then an exterior pathogen.
Half Exterior Half Interior syndrome: This refers to the process of disease development where the Zheng and Xie are contending, and the pathogenic factor cannot enter the interior, while the Zheng Qi cannot expel the pathogenic factor from the exterior, resulting in the pathogenic factor being between the exterior and interior. Clinical manifestations include alternating chills and fever, bitter taste in the mouth, dry throat, dizziness, fullness in the chest and hypochondria, irritability, nausea, and a wiry pulse.
Cold and Heat
Cold and Heat are the two principles for distinguishing the nature of diseases. Generally, Cold syndrome indicates insufficient Yang Qi or the reception of Cold pathogens, while Heat syndrome indicates excessive Yang Qi or the reception of Heat pathogens. The discussions on Cold and Heat in the “Huangdi Neijing” are extensive and clear, such as in the “Suwen: Discussion on Yin and Yang Correspondences,” which clearly states: “When Yang is excessive, it is Heat; when Yin is excessive, it is Cold.” In the “Suwen: Discussion on the True Essentials,” it is also proposed that “Cold transforms into Heat, and Heat transforms into Cold” as a treatment principle.
Cold Syndrome
Cold syndrome is characterized by the reception of Cold pathogens or the deficiency of Yang, leading to a decline in the body’s functional activities. Clinical symptoms include aversion to cold, preference for warmth, pale complexion, clear long urine, loose stools, pale tongue, white slippery coating, and a slow pulse. The etiology and pathogenesis are due to the reception of Cold pathogens or insufficient Yang Qi, leading to inadequate warming of the body, hence the aversion to cold, pale complexion, and preference for warmth; when Yin is excessive internally, the body fluids are not harmed, leading to no thirst; when Yang is insufficient, it cannot warm the body fluids, resulting in clear long urine and loose stools; when Yang Qi is insufficient, Cold and Dampness arise, leading to a pale tongue with white coating and a slow pulse.
Heat Syndrome
Heat syndrome is characterized by the reception of Heat pathogens or excessive Yang, leading to hyperactivity of the body’s functional activities. Clinical symptoms include fever, preference for coolness, thirst for cold drinks, red face, dry stools, red tongue with yellow coating, and a rapid pulse. The etiology and pathogenesis can arise from external reception of Fire and Heat pathogens, or from emotional disturbances, dietary excess, or overexertion, leading to Yin deficiency and Yang excess.
Relationship Between Cold and Heat Syndromes
Cold and Heat mixed: This refers to the simultaneous presence of Cold and Heat syndromes. Clinically, it is often seen as Upper Heat and Lower Cold, Upper Cold and Lower Heat, Exterior Cold and Interior Heat, and Exterior Heat and Interior Cold.
Upper Heat and Lower Cold: Yang is excessive in the upper body, while Yin is excessive in the lower body. Symptoms include heat in the chest, frequent vomiting (upper heat); abdominal pain with a preference for pressure, loose stools (lower cold).
Upper Cold and Lower Heat: Yin is excessive in the upper body, while Yang is excessive in the lower body. Symptoms include cold pain in the stomach, vomiting clear fluids (upper cold); short red urine, dry stools (lower heat).
Exterior Cold and Interior Heat: This occurs when the exterior is invaded by Cold pathogens, while the exterior has not resolved, and the pathogen enters the interior, transforming into heat. Symptoms include aversion to cold, fever, no sweating, body aches (exterior cold); shortness of breath, irritability, thirst for cold drinks, red urine, constipation (interior heat).
Exterior Heat and Interior Cold: This occurs when the exterior is affected by Wind-Heat, while the interior is affected by Cold. Symptoms include fever, headache, sore throat (exterior heat); clear long urine, loose stools, aversion to cold (interior cold).
Transformation of Cold and Heat: In clinical practice, the transformation of Cold and Heat can occur in two ways: one is the transition from Cold syndrome to Heat syndrome, where Cold symptoms gradually recede; the other is the transition from Heat syndrome to Cold syndrome, where Heat symptoms gradually recede. This transformation mainly depends on the relative strength of Zheng and Xie. Any transition from Cold to Heat indicates that the pathogenic factor is strong while Zheng Qi is still sufficient, leading to the transformation of Yang into Heat. For example, when Cold pathogens are received, the initial symptoms include aversion to cold, fever, body aches, no sweating, white coating, and floating tight pulse, indicating exterior cold syndrome. As the disease progresses, the Cold pathogen enters the interior, and the symptoms of aversion to cold recede, while symptoms of irritability, thirst, yellow coating, and rapid pulse appear, indicating the syndrome has transformed from exterior cold to interior heat.
When Heat transforms into Cold, it is often due to the pathogenic heat damaging Zheng Qi, leading to Yang Qi decline. For example, in cases of high fever, excessive sweating, or frequent vomiting and diarrhea, the Yang Qi is lost, leading to cold limbs, pale complexion, and a slow pulse, indicating the transformation from heat syndrome to cold syndrome.
True Cold and False Heat: This refers to the critical stage of the disease, where clinical signs may appear that are inconsistent with the nature of the disease, i.e., Heat symptoms appearing with Cold signs, and Cold symptoms appearing with Heat signs.
True Heat and False Cold: Yang heat is internally constrained and cannot express outwardly, leading to Cold symptoms on the exterior. Symptoms include a dull complexion, bright eyes, red lips, mental confusion, irritability, and a strong pulse.
True Cold and False Heat: Yin is excessive internally, leading to Yang being constrained externally. Symptoms include fever, red face, thirst, and a strong pulse, but the patient prefers to be covered, has cold limbs, and has a pale tongue with a white coating.
Deficiency and Excess
Deficiency and Excess diagnosis is a method for distinguishing the strength of Zheng and Xie. Any syndrome resulting from the decline, deficiency, or insufficiency of the body’s functions, or the loss of substances necessary for physiological activities, is termed Deficiency syndrome; any syndrome where the pathogenic Qi is relatively strong while Zheng Qi is not significantly deficient is termed Excess syndrome. The “Suwen: Discussion on the Evaluation of Deficiency and Excess” states, “When the pathogenic Qi is strong, it is Excess; when the essence and Qi are depleted, it is Deficiency,” which is the origin of the definitions of Deficiency and Excess.
Deficiency Syndrome
Deficiency syndrome is often seen after prolonged illness or severe illness, or in individuals with inherent weakness, leading to insufficient Zheng Qi and the appearance of syndromes related to the deficiency of organs, Qi, blood, Yin, and Yang. Symptoms include mental fatigue, pale complexion, fatigue, cold limbs, shortness of breath, or five hearts feeling hot, spontaneous sweating, night sweats, loose stools, frequent urination, pale tongue, and weak pulse. The etiology and pathogenesis of Deficiency syndrome can arise from congenital insufficiency or from insufficient nourishment acquired postnatally. For example, dietary imbalance can damage the spleen and stomach; emotional disturbances can injure the internal organs; excessive sexual activity can deplete the essence, and prolonged illness can damage Zheng Qi. Clinically, acquired deficiency is more common.
In clinical practice, Deficiency syndrome can be further divided into Exterior Deficiency and Interior Deficiency, as well as Deficiency Cold and Deficiency Heat.
Deficiency Cold syndrome is characterized by: Yang Qi deficiency, leading to insufficient warming. Symptoms include aversion to cold, cold limbs, abdominal pain with a preference for pressure, mental fatigue, clear long urine, loose stools, weak pulse, and pale tongue with white coating.
Deficiency Heat syndrome is characterized by: Insufficient Yin fluids leading to internal heat. Symptoms include tidal fever, night sweats, weight loss, five hearts feeling hot, dry throat, red tongue with little coating, and rapid pulse.
Excess Syndrome
Excess syndrome is often characterized by the presence of strong pathogenic Qi. Although the pathogenic Qi is strong, Zheng Qi is still able to resist it, and has not reached the point of deficiency. Therefore, it often represents a stage of intense struggle between Zheng and Xie, often due to external pathogens invading the body or internal organ dysfunction, leading to the accumulation of pathological products such as phlegm, dampness, and blood stasis. Symptoms include fever, abdominal distension and pain with a refusal to press, chest tightness, irritability, even mental confusion, shortness of breath, excessive phlegm, constipation, and a strong pulse with a thick coating. The etiology and pathogenesis of Excess syndrome can arise from either external invasion or from the accumulation of phlegm, dampness, and blood stasis.
In clinical practice, Excess syndrome can also be divided into Exterior Excess and Interior Excess, as well as Excess Heat and Excess Cold.
Excess Heat syndrome is characterized by: Excessive heat pathogens. Symptoms include high fever, thirst, mental confusion, abdominal distension and pain with a refusal to press, red tongue with yellow coating, and rapid pulse.
Excess Cold syndrome is characterized by: Excessive cold pathogens. Symptoms include aversion to cold, cold limbs, abdominal pain with a preference for pressure, constipation, and a strong pulse.
Relationship Between Deficiency and Excess Syndromes
The relationship between Deficiency and Excess syndromes can be categorized into three types: Deficiency and Excess mixed, transformation between Deficiency and Excess, and true and false Deficiency and Excess.
Deficiency and Excess mixed can present in six clinical manifestations:
1. Exterior Deficiency and Interior Excess: This occurs when the body’s Wei Yang is insufficient, and after receiving an external pathogen, it also injures the spleen. Symptoms include sweating, aversion to wind (Exterior Deficiency); abdominal distension and pain with a refusal to press, constipation, and yellow thick coating (Interior Excess).
2. Exterior Excess and Interior Deficiency: This occurs when the exterior pathogen has not resolved, while the interior Qi has already become deficient. Symptoms include fever, aversion to cold, no sweating (Exterior Excess); fatigue, cold limbs, poor appetite, or abdominal distension and pain with a preference for pressure (Interior Deficiency).
3. Upper Excess and Lower Deficiency: This occurs when phlegm obstructs the lungs, while the kidneys are deficient. Symptoms include cough and shortness of breath, excessive phlegm, chest tightness, and inability to lie flat (Upper Excess); lower back and knee pain, cold limbs, shortness of breath, and dizziness (Lower Deficiency).
4. Upper Deficiency and Lower Excess: This occurs when the heart is deficient in the upper body, while damp-heat descends. Symptoms include palpitations, anxiety, insomnia (Upper Deficiency); abdominal pain, diarrhea with pus and blood, and urgency (Lower Excess).
5. Mixed Deficiency with Excess: This occurs when the spleen and kidney Yang are deficient, leading to excessive water and dampness. Symptoms include cold pain in the knees, poor appetite, loose stools, and swelling (Mixed Deficiency with Excess).
6. Excess with Mixed Deficiency: This occurs when Qi and blood are stagnant, and Zheng Qi is already deficient. Symptoms include abdominal distension and pain, liver and spleen enlargement, and difficulty with bowel movements (Excess with Mixed Deficiency).
Transformation between Deficiency and Excess
In clinical practice, it is more common for Excess syndrome to transform into Deficiency syndrome, often due to improper treatment, excessive sweating, vomiting, or diarrhea, leading to depletion of Qi, blood, and body fluids. For example, when a patient presents with high fever, thirst, irritability, and a strong pulse, if treatment is inappropriate, over time, they may develop symptoms of weight loss, pale complexion, poor appetite, fatigue, and a weak pulse, indicating a transition to Deficiency syndrome.
It is less common for Deficiency syndrome to transform into Excess syndrome, which usually occurs due to insufficient Zheng Qi, leading to the generation of phlegm, dampness, and blood stasis.
True Deficiency and False Excess: In the process of disease development, when Excess syndrome reaches an extreme stage, symptoms similar to Deficiency syndrome may appear; conversely, when Deficiency syndrome reaches a certain stage, symptoms similar to Excess syndrome may also appear. In clinical practice, comprehensive analysis is necessary to make an accurate diagnosis.
True Deficiency and False Excess: This occurs when the Zheng Qi is severely deficient, leading to insufficient Qi and blood, and the body cannot function properly, resulting in symptoms of abdominal pain and distension, or high fever with a strong pulse (False Excess). However, abdominal distension may sometimes alleviate, and the pulse may be weak upon pressure; or the tongue may appear pale or swollen (True Deficiency).
True Excess and False Deficiency: This occurs when pathogenic factors are internally constrained, leading to symptoms of abdominal distension and pain, refusal to press, and constipation (True Excess); however, the patient may also present with mental fatigue and a weak pulse (False Deficiency).
Diagnosis
Diagnosis involves identifying symptoms based on the data obtained from the four examinations to analyze, synthesize, and summarize the causes, locations, and nature of the disease, thereby making an accurate diagnosis to provide a basis for treatment.
“Zheng” and “Symptom” should be strictly distinguished. “Symptom” refers to individual symptoms, while “Zheng” refers to the syndrome, which is the result obtained from diagnosis.
The concepts of “Zheng” and “Disease” are different. Qing dynasty physician Xu Lingtai stated: “The totality of the disease is called the disease, while one disease can encompass multiple syndromes.” This means that a disease can encompass various syndromes.
Diagnosing the disease name must first involve diagnosing the syndrome. Diagnosis begins with syndrome differentiation, followed by disease differentiation, and then further syndrome differentiation after disease diagnosis. Therefore, syndrome differentiation and treatment do not imply that TCM does not emphasize disease differentiation; rather, it includes disease differentiation within the scope of syndrome differentiation.
There are many methods for syndrome differentiation, which have been formed through long-term clinical practice, such as differentiation based on etiology, differentiation of Qi, blood, and body fluids, differentiation of organs, differentiation of meridians, differentiation of the six meridians, differentiation of Wei, Qi, Ying, and blood, and differentiation of the three Jiao. Among these, differentiation based on etiology focuses on identifying syndromes from the perspective of etiology, which can be seen as the foundation for differentiating external diseases.
Six Meridian Differentiation is a method for differentiating the febrile disease known as “Shanghan”; Wei, Qi, Ying, and blood differentiation is a method for differentiating the febrile disease known as “Wenbing.” Differentiation of meridians, Qi, blood, and body fluids is applicable to various miscellaneous diseases. However, differentiation of organs is the key method for differentiating miscellaneous diseases, while differentiation of meridians and differentiation of Qi, blood, and body fluids can be seen as complementary methods to organ differentiation.
Qi, Blood, and Body Fluids Differentiation
Qi, blood, and body fluids are the products of the normal physiological activities of the organs, governed by the organs, and they are the material basis for the life activities of the human body. Once Qi, blood, and body fluids undergo pathological changes, they not only affect the functions of the organs but also impact the life activities of the body. Conversely, when the organs undergo pathological changes, they will inevitably affect the changes in Qi, blood, and body fluids. Qi, blood, and body fluids differentiation can be divided into differentiation of Qi diseases, blood diseases, and body fluid diseases.
Qi Disease Differentiation
Common syndromes of Qi disease can be summarized as Qi Deficiency, Qi Sinking, Qi Stagnation, and Qi Reversal.
Qi Deficiency syndrome refers to the symptoms arising from the damage to the body’s nutrients or the decline in the functional activities of the organs.
Symptoms: include dizziness, shortness of breath, fatigue, spontaneous sweating, and symptoms that worsen with activity, pale tongue, and weak pulse.
Etiology and pathogenesis: Often caused by prolonged illness, dietary imbalance, or aging and weakness.
Qi Sinking syndrome is a type of Qi Deficiency characterized by the inability of Qi to rise.
Symptoms: include dizziness, shortness of breath, a feeling of heaviness in the abdomen, prolapse of the rectum or uterus, and pale tongue with white coating, and weak pulse.
Etiology and pathogenesis: Qi deficiency leads to organ function decline, resulting in the failure of clear Yang to rise, causing Qi to sink.
Qi Stagnation syndrome refers to the obstruction of Qi flow in certain areas or organs, leading to pathological changes.
Symptoms: include distension, pain, and varying intensity, often alleviated by warmth or gas release.
Etiology and pathogenesis: Can be caused by external six excesses, internal emotional disturbances, dietary issues, or trauma.
Qi Reversal syndrome refers to the upward reversal of Qi flow, often seen in the lungs, stomach, and liver.
Symptoms: include cough and shortness of breath for lung Qi, belching, nausea, and vomiting for stomach Qi, and headache, dizziness, and vomiting blood for liver Qi.
Etiology and pathogenesis: Often due to external pathogens affecting the lungs or phlegm obstructing the lungs.
Blood Disease Differentiation
Common syndromes of blood disease can be summarized as Blood Deficiency, Blood Stasis, and Blood Heat.
Blood Deficiency syndrome refers to symptoms arising from the deficiency of blood in the body.
Symptoms: include pale complexion, pale lips, fatigue, dizziness, palpitations, insomnia, numbness in the hands and feet, and women experiencing scanty menstruation or amenorrhea, pale tongue, and weak pulse.
Etiology and pathogenesis: Often due to prolonged illness, blood loss (vomiting, bleeding, etc.), or weakness of the spleen and stomach.
Blood Stasis syndrome refers to the obstruction of blood flow in the body, leading to pathological changes.
Symptoms: include localized pain, fixed pain, or lumps, and may also include bleeding with dark blood and purple tongue.
Etiology and pathogenesis: Often due to Qi stagnation, cold, heat, or trauma.
Blood Heat syndrome refers to the presence of heat in the blood or heat entering the blood.
Symptoms: include irritability, thirst, fever, red tongue, rapid pulse, and may also include bleeding.
Etiology and pathogenesis: Often due to external heat invasion or emotional disturbances.
Body Fluid Disease Differentiation
Body fluid diseases refer to disorders caused by metabolic disturbances of water and fluids or the deficiency of body fluids.
Body fluid diseases can generally be summarized as Body Fluid Deficiency and Water Accumulation.
Body Fluid Deficiency syndrome, also known as Body Fluid Damage syndrome, refers to the symptoms caused by the loss of body fluids.
Symptoms: include dryness of the lips, tongue, throat, and skin, muscle wasting, thirst, constipation, and reduced urination, with a red tongue and thin rapid pulse.
Etiology and pathogenesis: Often due to excessive sweating, bleeding, vomiting, diarrhea, or heat damaging body fluids.
Water Accumulation syndrome refers to the retention of water and dampness due to dysfunction of the lungs, spleen, kidneys, and San Jiao.
Accumulated water can lead to phlegm, dampness, and edema.
Phlegm can be classified into wind phlegm, heat phlegm, cold phlegm, damp phlegm, and dry phlegm, each with distinct clinical manifestations.
1. Wind Phlegm: Yin deficiency with Yang excess, leading to wind phlegm. Symptoms include dizziness, phlegm in the throat, sudden collapse, facial droop, and paralysis.
2. Heat Phlegm: Heat invasion or Yang excess leading to phlegm heat. Symptoms include fever, yellow phlegm, and irritability.
3. Cold Phlegm: Cold invasion or Yin excess leading to phlegm. Symptoms include aversion to cold, cough with clear phlegm, and cold limbs.
4. Damp Phlegm: Spleen deficiency leading to dampness. Symptoms include chest tightness, poor appetite, and excessive phlegm.
5. Dry Phlegm: Dryness leading to phlegm. Symptoms include difficulty expectorating phlegm, dry mouth, and constipation.
Accumulated water can be classified into phlegm fluid, suspended fluid, and overflow fluid.
1. Phlegm Fluid: Spleen deficiency leading to phlegm accumulation. Symptoms include chest tightness, clear phlegm, and dizziness.
2. Suspended Fluid: Yang deficiency leading to fluid retention. Symptoms include pain in the ribs and difficulty breathing.
3. Overflow Fluid: Yang deficiency leading to fluid retention in the limbs. Symptoms include heaviness in the limbs and difficulty urinating.
Organ Differentiation
Organ differentiation is a method of analyzing and summarizing the physiological functions and pathological manifestations of the organs, combined with the theories of etiology, Eight Principles, Qi, blood, and body fluids, to determine the causes, locations, and nature of diseases. It is an important component of TCM diagnostic theory. The five organs form a unified whole, and there are relationships between the organs. Therefore, organ diseases can exhibit interrelated and overlapping characteristics, leading to various syndromes of multiple organ involvement.
Organ differentiation can be discussed from the perspectives of heart and small intestine, lung and large intestine, spleen and stomach, liver and gallbladder, kidney and bladder, and organ combinations.
Heart and Small Intestine Differentiation
The heart is located in the chest and is paired with the small intestine. The heart governs the spirit, blood vessels, sweat, fire, and opens to the tongue, with its manifestation in the face and its emotion being joy. Common syndromes of heart disease include:
Heart Qi Deficiency and Heart Yang Deficiency
Symptoms: Both present with palpitations, shortness of breath, worsening with activity, and a weak or irregular pulse. Accompanied by pale complexion, fatigue, spontaneous sweating, pale tongue, and weak pulse indicates Heart Qi Deficiency; while cold limbs, pale complexion, chest tightness, and dark tongue indicates Heart Yang Deficiency. Severe cases may present with profuse sweating, cold limbs, cyanosis, weak breathing, and fainting.
Etiology and pathogenesis: Often due to prolonged illness, aging, excessive sweating, or insufficient constitution.
Heart Blood Deficiency and Heart Yin Deficiency
Symptoms: Both present with palpitations, forgetfulness, insomnia, and vivid dreams. Accompanied by dizziness, pale complexion, pale lips, and weak pulse indicates Heart Blood Deficiency; while irritability, dry mouth, and red tongue with little coating indicates Heart Yin Deficiency.
Etiology and pathogenesis: Often due to insufficient blood production, blood loss, or emotional disturbances.
Heart Fire Excess and Small Intestine Heat
Symptoms: Heart heat presents with irritability, insomnia, thirst, and red tongue; Small Intestine heat may present with blood in urine and burning pain.
Etiology and pathogenesis: Often due to emotional disturbances, excessive spicy food, or heat invasion.
Heart Vessel Obstruction
Symptoms: Chest pain or tightness, palpitations, cyanosis, and dark tongue.
Etiology and pathogenesis: Often due to Qi or Yang deficiency leading to obstruction.
Phlegm Fire Disturbing the Heart
Symptoms: Mild cases present with irritability, red face, and incoherent speech; severe cases may present with confusion and agitation.
Etiology and pathogenesis: Often due to emotional disturbances leading to phlegm heat.
Lung and Large Intestine Differentiation
The lungs are located in the chest and are paired with the large intestine. The lungs govern Qi, respiration, and skin, and are responsible for the distribution of body fluids. Common syndromes of lung disease include:
Lung Qi Deficiency
Symptoms: Shortness of breath, cough with weak phlegm, spontaneous sweating, pale complexion, and weak pulse.
Etiology and pathogenesis: Often due to prolonged illness or insufficient constitution.
Lung Yin Deficiency
Symptoms: Dry cough, little phlegm, or blood-streaked phlegm, afternoon fever, and red tongue.
Etiology and pathogenesis: Often due to prolonged cough or heat damaging the lungs.
Wind Cold Binding the Lungs
Symptoms: Cough with heavy sound, white phlegm, nasal congestion, fever, headache, and no sweating.
Etiology and pathogenesis: Often due to external wind-cold invasion.
Wind Heat Invading the Lungs
Symptoms: Cough with coarse sound, yellow phlegm, thirst, and sore throat.
Etiology and pathogenesis: Often due to external wind-heat invasion.
Phlegm Heat Obstructing the Lungs
Symptoms: Cough with shortness of breath, fever, chest pain, and yellow phlegm.
Etiology and pathogenesis: Often due to heat invasion or phlegm accumulation.
Dry Evil Invading the Lungs
Symptoms: Dry cough, little phlegm, and dry throat.
Etiology and pathogenesis: Often due to autumn dryness.
Large Intestine Damp Heat
Symptoms: Fever, abdominal pain, diarrhea, burning sensation in the anus, or blood in stool.
Etiology and pathogenesis: Often due to dietary indiscretion or external damp heat invasion.
Large Intestine Qi Deficiency
Symptoms: Dry stools, pale tongue, and weak pulse.
Etiology and pathogenesis: Often due to prolonged illness or insufficient constitution.
Spleen and Stomach Differentiation
The spleen is located in the middle jiao and is paired with the stomach. The spleen governs transportation and transformation, and is responsible for the distribution of body fluids. Common syndromes of spleen disease include:
Spleen Qi Deficiency
Symptoms: Poor appetite, abdominal distension, fatigue, pale complexion, and weak pulse.
Etiology and pathogenesis: Often due to prolonged illness or dietary indiscretion.
Spleen Yang Deficiency
Symptoms: Abdominal distension, loose stools, cold limbs, and pale tongue.
Etiology and pathogenesis: Often due to prolonged illness or excessive cold foods.
Spleen Damp Heat
Symptoms: Abdominal distension, nausea, and poor appetite.
Etiology and pathogenesis: Often due to dietary indiscretion or external damp heat invasion.
Stomach Cold
Symptoms: Cold pain in the stomach, improved with warmth.
Etiology and pathogenesis: Often due to cold invasion.
Stomach Heat
Symptoms: Burning pain in the stomach, thirst, and preference for cold drinks.
Etiology and pathogenesis: Often due to heat invasion.
Liver and Gallbladder Differentiation
The liver is located in the right hypochondrium and is paired with the gallbladder. The liver governs the smooth flow of Qi and blood, and is responsible for the storage of blood. Common syndromes of liver disease include:
Liver Qi Stagnation
Symptoms: Emotional disturbances, irritability, chest and hypochondriac pain, and poor appetite.
Etiology and pathogenesis: Often due to emotional disturbances.
Liver Fire Excess
Symptoms: Headache, irritability, red eyes, and bitter taste in the mouth.
Etiology and pathogenesis: Often due to emotional disturbances or dietary indiscretion.
Liver Yang Rising
Symptoms: Dizziness, headache, and irritability.
Etiology and pathogenesis: Often due to emotional disturbances or Yang excess.
Liver Blood Deficiency
Symptoms: Dizziness, pale complexion, and poor appetite.
Etiology and pathogenesis: Often due to prolonged illness or blood loss.
Liver Wind Internal Movement
Symptoms: Tremors, spasms, and dizziness.
Etiology and pathogenesis: Often due to blood deficiency or Yang excess.
Kidney and Bladder Differentiation
The kidneys are located on either side of the lower back and are paired with the bladder. The kidneys store essence, govern reproduction, and control water metabolism. Common syndromes of kidney disease include:
Kidney Yin Deficiency
Symptoms: Dizziness, tinnitus, and low back pain.
Etiology and pathogenesis: Often due to prolonged illness or excessive sexual activity.
Kidney Yang Deficiency
Symptoms: Cold limbs, low back pain, and frequent urination.
Etiology and pathogenesis: Often due to prolonged illness or excessive cold foods.
Kidney Qi Deficiency
Symptoms: Fatigue, low back pain, and frequent urination.
Etiology and pathogenesis: Often due to prolonged illness or excessive sexual activity.
Bladder Damp Heat
Symptoms: Painful urination, frequent urination, and burning sensation.
Etiology and pathogenesis: Often due to external damp heat invasion.
Bladder Deficiency Cold
Symptoms: Frequent urination with clear urine, or incontinence.
Etiology and pathogenesis: Often due to kidney Yang deficiency.
Organ Combinations
When two or more organs are affected simultaneously, it is termed organ combinations.
Heart and Spleen Deficiency
Symptoms: Palpitations, forgetfulness, insomnia, poor appetite, and fatigue.
Etiology and pathogenesis: Often due to prolonged illness or emotional disturbances.
Heart and Kidney Disharmony
Symptoms: Insomnia, palpitations, dizziness, and low back pain.
Etiology and pathogenesis: Often due to emotional disturbances or excessive sexual activity.
Heart and Kidney Yang Deficiency
Symptoms: Cold limbs, palpitations, and fatigue.
Etiology and pathogenesis: Often due to prolonged illness or excessive cold foods.
Heart and Lung Qi Deficiency
Symptoms: Palpitations, shortness of breath, and fatigue.
Etiology and pathogenesis: Often due to prolonged illness or excessive cold foods.
Liver and Spleen Disharmony
Symptoms: Chest and hypochondriac pain, irritability, and poor appetite.
Etiology and pathogenesis: Often due to emotional disturbances.
Liver and Stomach Disharmony
Symptoms: Chest and hypochondriac pain, irritability, and poor appetite.
Etiology and pathogenesis: Often due to emotional disturbances.
Liver and Kidney Yin Deficiency
Symptoms: Dizziness, tinnitus, and low back pain.
Etiology and pathogenesis: Often due to prolonged illness or excessive sexual activity.
Three Jiao Differentiation
Since the Qing dynasty physician Wu Jutong’s “Wenbing Tiaobian” discussed the differentiation of warm diseases based on the upper, middle, and lower Jiao, Three Jiao Differentiation has become one of the methods for differentiating warm diseases. This method is based on the concept of the locations of the three Jiao in the “Huangdi Neijing,” combined with the characteristics of the transmission of warm diseases.
Three Jiao Differentiation emphasizes the pathological changes of the organs associated with the upper, middle, and lower Jiao, the characteristics of the syndromes, and the rules of transmission. It is believed that warm diseases generally begin in the upper Jiao (hand Taiyin lung), then transmit to the middle Jiao (spleen and stomach), and finally reach the lower Jiao (liver and kidney). However, due to the different types of warm diseases, such as wind warmth, spring warmth, summer heat, damp warmth, autumn dryness, and pestilence, their onset and transmission rules vary.
In Three Jiao Differentiation, the pathogenic factors in the upper Jiao mainly manifest as changes in the hand Taiyin lung and hand Jueyin heart meridians. Diseases in the middle Jiao reflect dysfunction of the spleen and stomach. When the pathogenic factors enter the lower Jiao, they mainly reflect changes in the foot Jueyin liver and foot Shaoyin kidney. Diseases in the upper and middle Jiao are mostly Excess syndromes, while diseases in the lower Jiao are mostly Deficiency syndromes.
Upper Jiao Disease
Wind Heat Invading the Exterior: Refers to the invasion of wind-heat pathogens affecting the lung Wei function. Symptoms include fever, mild aversion to wind and cold, headache, cough, and a thin white coating.
Heat Obstructing the Lungs: Refers to heat obstructing the lungs, leading to symptoms of fever, sweating, cough, and shortness of breath.
Heart Vessel Obstruction: Refers to the invasion of phlegm-heat pathogens affecting the heart, leading to symptoms of fever, confusion, and cyanosis.
Middle Jiao Disease
Stomach Heat Syndrome: Refers to heat in the stomach leading to symptoms of fever, irritability, and thirst.
Intestinal Heat Accumulation: Refers to heat and stagnation in the intestines leading to symptoms of fever, abdominal pain, and constipation.
Spleen Damp Heat: Refers to damp heat invading the spleen leading to symptoms of fatigue, poor appetite, and abdominal distension.
Lower Jiao Disease
Kidney Yin Deficiency: Refers to heat damaging the kidney Yin leading to symptoms of fever, night sweats, and irritability.
Wind Movement Due to Yin Deficiency: Refers to the internal movement of wind due to Yin deficiency leading to symptoms of tremors and spasms.
In addition, many other symptoms of warm diseases can also be classified under the Three Jiao disease category, such as warm heat invading the Wei, dry heat invading the Wei, phlegm heat obstructing the lungs, dry heat injuring the lungs, heat obstructing the chest, etc., which all belong to upper Jiao diseases. Heat obstructing the gallbladder, summer heat injuring Qi and body fluids, etc., belong to middle Jiao diseases. Qi heat movement, Ying heat movement, heat entering the Ying, blood heat movement, and blood heat movement all belong to lower Jiao diseases.
Diagnosis of Diseases
Symptoms are the various abnormal sensations or changes in the body that patients feel or that doctors observe during diagnosis. For example, headache, dizziness, etc. They are manifestations of the body after the onset of disease and are objective signs for doctors to diagnose diseases.
Symptoms and syndromes are completely different concepts. A syndrome, abbreviated as “Zheng,” is a comprehensive summary of the causes, pathogenesis, location, symptoms, tongue diagnosis, and pulse diagnosis. For example, Exterior Excess syndrome, Yin Deficiency syndrome, etc. It reflects the essence of the disease and is the conclusion of clinical diagnosis.
The concepts of “Zheng” and “Disease” are different. Qing dynasty physician Xu Lingtai stated: “The totality of the disease is called the disease, while one disease can encompass multiple syndromes.” This means that a disease can encompass various syndromes.
Diagnosing the disease name must first involve diagnosing the syndrome. Diagnosis begins with syndrome differentiation, followed by disease differentiation, and then further syndrome differentiation after disease diagnosis. Therefore, syndrome differentiation and treatment do not imply that TCM does not emphasize disease differentiation; rather, it includes disease differentiation within the scope of syndrome differentiation.
There are many methods for syndrome differentiation, which have been formed through long-term clinical practice, such as differentiation based on etiology, differentiation of Qi, blood, and body fluids, differentiation of organs, differentiation of meridians, differentiation of the six meridians, differentiation of Wei, Qi, Ying, and blood, and differentiation of the three Jiao. Among these, differentiation based on etiology focuses on identifying syndromes from the perspective of etiology, which can be seen as the foundation for differentiating external diseases.
Six Meridian Differentiation is a method for differentiating the febrile disease known as “Shanghan”; Wei, Qi, Ying, and blood differentiation is a method for differentiating the febrile disease known as “Wenbing.” Differentiation of meridians, Qi, blood, and body fluids is applicable to various miscellaneous diseases. However, differentiation of organs is the key method for differentiating miscellaneous diseases, while differentiation of meridians and differentiation of Qi, blood, and body fluids can be seen as complementary methods to organ differentiation.
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