Therapeutic Principles

Therapeutic principles are the criteria of treating all diseases. Formulated under the guidance of the concept of holism and treatment based on syndrome differentiation, they are significant for clinically guiding the determination of therapeutic methods, prescription and drugs.

Therapeutic principles are different from therapies. Guided by the former, the latter refers to the therapeutic rules and methods in accordance with various syndromes. Therapeutic rules are the criteria of classified treatment, and give specific guidance to therapeutic methods. They include diaphoresis, emesis, purgation, mediating, warming, heat-clearing, resoluting and reinforcing, also known as "major therapeutic rules". Extensively used in clinical practice, these eight rules are on the highest level among therapeutic rules. Whereas, therapeutic methods are those specific for various syndromes, limited in the range of therapeutic rules, such as nourishing blood to induce tranquilization, and releasing superficies with pungent-warm drugs, etc. Under the guidance of therapies, therapeutic measures should be further selected and determined, including oral use of drugs, acupuncture, tuina, external application, fumigation and washing.

Search for the fundamental of disease in treatment

It means to find the fundamental cause of a disease and focus the treatment on it. Reflecting the concept of holism and treatment based on syndrome differentiation, it is also a universal principle in traditional Chinese medicine when applying treatment to disease.

It includes routine treatment, contrary treatment and treating the fundamental and incidental aspects.

1. Routine treatment and contrary treatment

A. Routine treatment:

It refers to the treatment of disease adverse to its manifestations (symptoms and signs), also known as "adverse treatment", applicable to disease with nature in conformity with its manifestations. For example, warm syndrome is marked by warm manifestations, cold syndrome by cold manifestations, deficiency syndrome by deficiency manifestations, and excess syndrome by excess manifestations. Since the nature (cold, hot, tonifying, purgative, etc.) and the action tendency of drugs are opposite to the manifestations of disease, it is accordingly known as "adverse treatment". Additionally, in clinic practice, manifestations of most disease are in conformity with the nature of disease, so treatment adverse to manifestations of disease is a general therapeutic principle, termed as "routine treatment". It includes the followings:

a. Treat cold with heat:

It means that the cold syndrome, with cold manifestations, should be treated with warming or hot formula. For example, releasing superficies with pungent-warm drugs is used to treat wind-cold syndrome of exterior type, and warming interior with pungent-hot drugs to treat the interior cold syndrome.

b. Treat heat with cold:

It means that the heat syndrome, with heat manifestations, should be treated with cold or cool formula. For example, releasing superficies with pungent-cool drugs is used to treat wind-heat syndrome of exterior type, and relieving interior with bitter-cold drugs to treat heat accumulation in the stomach and intestines.

c. Treat deficiency by tonifying:

It means that deficiency of healthy qi, with deficiency manifestations, should be treated with tonifying and replenishing formula. For example, replenishing qi is used to treat the qi deficiency syndrome, and nourishing yin to treat the yin deficiency syndrome.

d. Treat excess by purging:

It means that excess of pathogenic qi, with excess manifestations, should be treated with offensive purgative formula. For example, dispelling retained water is used to treat internal retention of water, and promoting digestion and removing food stagnation to treat food stagnation.

B. Contrary treatment:

It refers to the treatment of disease agreeable to its manifestations, also known as "agreeable treatment", applicable to complicated morbid states in which the nature of disease is not completely in conformity with its manifestations, or even marked by false manifestations. For example, heat syndrome is marked by cold manifestations, cold syndrome by heat manifestations, deficiency syndrome by excess manifestations, and excess syndrome by deficiency manifestations. Since the nature (cold, hot, tonifying, purgative, etc.) and the action tendency of formula are agreeable to the manifestations of disease, it is accordingly known as "agreeable treatment". Since this kind of case is seldom seen in clinic practice and opposite to routine treatment, it is termed as "contrary treatment". It mainly includes the following:

a. Treat heat with heat:

It means that diseases with manifestations of false heat should be treated with warm or hot formula or measures, applicable to the syndrome of true cold with false heat caused by exuberant yin with repelled yang. For example, in Shanghan Lun (Treaties on Cold-Induced Disease), warm and hot formula, namely Tong Mai Si Ni Tang (Tongmaisini Decoction), is used to treat this case. When the pathogenic qi of yin cold is cleared away, false heat will disappear subsequently.

b. Treat cold with cold:

It means that diseases with manifestations of false cold should be treated with cold or cool formula or measures, applicable to the syndrome of true heat with false cold caused by exuberant yang with repelled yin. For example, in Shanghan Lun (Treaties on Cold-Induced Disease), cold and cool formula, namely Baihu Tang (Baihu decoction), is used to treat heat syncope caused by exuberant internal yang with yin repelled externally. When the pathogenic qi of yang heat is cleared away, false cold will disappear subsequently.

c. Treat stuffiness with tonic:

It means that diseases with manifestations of stuffiness should be treated with tonifying and replenishing formula or measures, also known as "relieving stuffiness with tonic", applicable to the syndrome of stuffiness and stagnation caused by deficiency. For example, abdominal distension and fullness, caused by deficiency of spleen and stomach and qi stagnation, is treated by invigorating spleen and replenishing qi. When the spleen and stomach function normally in transportation, distension and fullness will disappear spontaneously. For more examples, constipation due to qi deficiency, dysuria due to kidney deficiency and amenorrhea due to blood exhaustion can all be treated by "relieving stuffiness with tonic" with tonifying and replenishing formula.

d. Treat diarrhea with purgative:

It means that diseases with manifestations of diarrhea should be treated with purgative formula or measures, applicable to the syndrome of diarrhea caused by stagnation of excess pathogens. For example, dysentery caused by stagnation of damp-heat in the large intestine abdominal distension and fullness is treated by clearing heat and draining heat as well as promoting qi flow and relieving stagnation. When damp and heat are cleared away, diarrhea will be stopped spontaneously. For more examples, diarrhea caused by dyspepsia and metrorrhagia and metrostaxis caused by stagnant blood can be treated respectively with digestive formula and blood-activating and stasis-resoving formula, which are the so-called "treat diarrhea with purgative".

Routine treatment is different from contrary treatment. The former is the routing treatment of disease adverse to its manifestations, applicable to disease with nature in conformity with its manifestations. The latter is contrary to the routine treatment but agreeable to manifestations of disease, applicable to complicated morbid states in which the nature of disease is not completely in conformity with its manifestations or even marked by false manifestations. Besides, routine treatment and contrary treatment share some common points, i.e. both of them focus on the nature of disease, so they both pertain to search for the fundamental of disease in treatment".

2. Treating fundamental aspect and incidental aspect

A. Concepts of fundamental aspect and incidental aspect

The fundamental and the incidental are two relatively opposite concepts. Their relationship is often used to generalize and explain the essence and the outward appearance. In traditional Chinese medicine, it is mainly used to illuminate the relationship between the primary and the secondary of various contradictions during the course of a disease. Generally speaking, the fundamental is primary contradiction or the primary aspect of a contradiction; while the incidental is secondary contradiction or the secondary aspect of a contradiction. In the course of a disease, its fundamental aspect and incidental aspect are determined by the development of the disease. For example, healthy qi is the fundamental aspect, and pathogenic qi the incidental aspect; the cause of disease is the fundamental aspect, and the symptoms incidental aspect; primary disease is the fundamental aspect, and secondary disease the incidental aspect.

B. Application of treating fundamental aspect and incidental aspect

Disease has aspects of the fundamental and the incidental, or aspects of the primary and the secondary, and treatment can be carried out in order of time and urgency. Only by resolving the primary contradiction of a disease first after distinguishing the fundamental from the incidental and the primary from the secondary, can the essence of treatment be grasped: treating incidental aspect, treating fundamental aspect, or treating both fundamental and incidental aspects.

a. Treating fundamental aspect in case of lesser urgency

For chronic disease or acute disease at the recovery stage, treatment should be focused on the fundamental aspect of a disease, for the incidental aspect usually originates from the fundamental aspect. When the fundamental aspect is cured, the incidental aspect will disappear subsequently. Take cough due to tuberculosis for example. Yin deficiency of the lung and kidney are the fundamental aspects, while cough is the incidental aspect. Therefore, it should he treated by nourishing yin of the lung and kidney, which is to treat the fundamental aspect. When yin fluid of the lung and kidney moistens, cough will be relieved naturally.

b. Treating incidental aspect in case of urgency

When the incidental aspect of a disease is so urgent and serious that it affects the treatment of the fundamental aspect and endangers patient's life, treatment should be focused on it first. For example, hematorrhea of any reason should be treated by arresting bleeding first, which is to treat the incidental aspect. When bleeding is stopped, its fundamental aspect should be further searched for and treated later on. It is thus evident that treating incidental aspect in case of urgency is actually an expedient measure. It means to create favorable conditions for the treatment of the fundamental aspect and aims to finally better treat its fundamental aspect.

Moreover, for those who suffer from old chronic disease and newly contract other pathogens, the old disease is the fundamental aspect and the new contraction is the incidental aspect. Although the incidental aspect is not very urgent, if not treated first, it will affect the treatment of the fundamental aspect. Therefore, the new contraction should be treated ahead of the old one.

c. Treating both fundamental and incidental aspects

When the incidental and fundamental aspects of a disease are both serious or both not urgent, treatment should be concentrated on both fundamental and incidental aspects. Take common cold caused by qi deficiency for example. Qi deficiency is the fundamental aspect, and cold is the incidental aspect. Then simply replenishing qi will cause stagnation of pathogenic qi and cold cannot be cured; simply releasing superficies will impair healthy qi. Only by replenishing qi and releasing superficies, or by treating both fundamental and incidental aspects, can cold get relieved. Thus, the principle of treating both fundamental and incidental aspects can be applied to diseases complicated with coexistence of exterior and interior syndromes as well as mixture of deficiency and excess.

Reinforcing the healthy and eliminating the pathogenic

Struggle between the healthy and pathogenic qi determines the development of a disease. With preponderance of pathogenic qi and decline of healthy qi, disease will progress; with preponderance of healthy qi and decline of pathogenic qi, disease will regress. To change the relative strength of pathogenic and healthy qi and to promote recovery of disease, the healthy qi should be reinforced and the pathogenic qi should be eliminated.

1. Concepts and relationships of reinforcing the healthy and eliminating the pathogenic

A. Reinforcing the healthy

It refers to tonify the healthy qi, build up constitutions, and improve the body's resistance against disease and recovery ability. it is mainly applied to deficiency syndrome, which means to "treat deficiency by tonifying". Such therapeutic methods as replenishing qi, nourishing blood and yin, and warming yang are all guided by this principle. The specific measures of reinforcing the healthy are diverse, including drugs, acupuncture and moxibustion, qigong, regulation of emotions and diet, physical exercise, etc.

B. Eliminating the pathogenic

It refers to remove the pathogenic qi and to relieve the invasion and impairment of pathogenic qi. It is mainly applied to excess syndrome, which means to "treat excess by purging". Such therapeutic methods as diaphoresis, emesis, purgation, resolving food stagnation, resolving phlegm, activating blood, dispersing cold, clearing away heat and dispelling dampness are all guided by this principle. The specific measures of eliminating the pathogenic are also diverse, including drugs, acupuncture and moxibustion, tuina, etc.

C. Relationship between reinforcing the healthy and eliminating the pathogenic

Reinforcing the healthy and eliminating the pathogenic are complementary. Reinforcing the healthy helps to tonify healthy qi and to prevent and dispel pathogenic qi, i. e. "when healthy qi is exuberant, pathogenic qi will be dispelled naturally"; whereas, eliminating the pathogenic helps to remove pathogenic factors and to conserve and recover healthy qi, i. e. , "when pathogenic qi is driven out of the body, healthy qi will recover naturally". Thus, reinforcing the healthy helps to eliminate pathogenic qi, while eliminating the pathogenic helps to reinforce healthy qi. But they are two completely different therapeutic principles. Drugs of reinforcing the healthy tend to make pathogenic qi retain in the body, while drugs of eliminating the pathogenic tend to impair the healthy qi. So clinically, the increase or decrease of healthy or pathogenic qi should be first carefully analyzed to decide whether to reinforce the healthy, or to eliminate the pathogenic,or to combine both together.

2. Application of reinforcing the healthy and eliminating the pathogenic

Generally speaking, reinforcing the healthy is used for deficiency syndrome, while eliminating the pathogenic is used for excess syndrome. If a syndrome is mixed with deficiency of healthy qi and excess of pathogenic qi, it should he treated by both reinforcing the healthy and eliminating the pathogenic. During the treatment, attention should be paid to differentiate what is primary from what is secondary and what is urgent from what is less urgent, so that reinforcing the healthy and eliminating the pathogenic can be taken up in order of importance and priority.

A. Single application

a. Reinforcing the healthy

It is applicable to deficiency syndrome in which deficiency of healthy qi is the primary contradiction and meanwhile pathogenic qi is not exuberant. It is realized by tonifying and replenishing. For example, qi deficiency is treated by replenishing qi, blood deficiency by tonifying blood, yang deficiency by strengthening yang, yin deficiency by replenishing yin, etc.

b. Eliminating the pathogenic

It is applicable to excess syndrome in which exuberance of pathogenic qi is the primary contradiction and meanwhile healthy qi does not decline. It is realized by purgation. For example, excess of exterior pathogens is treated by inducing sweating to release superficies, phlegm, saliva and retained food due to pathogens retained in the chest are treated by emesis, heat accumulation in the stomach and intestines is treated by purgation with bitter cold drugs, accumulation of heat and fire is treated by clearing away heat and purging fire, etc.

B. Combined application

a. Reinforcing the healthy combined with eliminating the pathogenic

Reinforcing the healthy is the main focus of treatment and eliminating the pathogenic is also taken into consideration. It is applicable to syndromes with deficiency of healthy qi as the primary contradiction and exuberance of pathogenic qi as the secondary contradiction. For such syndromes, if healthy qi is not reinforced, pathogenic qi will become more savage; whereas, if pathogenic qi is not eliminated, healthy qi will be impaired further. Therefore, reinforcing the healthy combined with eliminating the pathogenic should be used. For exampte, heart vessel obstruction syndrome caused by deficiency of heart qi should he treated by tonifying and replenishing heart qi combined with activating blood and resolving stasis.

b. Eliminating the pathogenic combined with reinforcing the healthy

Eliminating the pathogenic is the main focus of treatment and reinforcing the healthy is also taken into consideration. It is applicable to syndromes with exuberance of pathogenic qi as the primary contradiction and deficiency of healthy qi as the secondary contradiction. For such syndromes, if pathogenic qi is not eliminated, healthy qi will be impaired further; whereas, if healthy qi is not reinforced, pathogenic qi will become more savage. Therefore, treatment should be focused on reinforcing the healthy and simultaneously be combined with eliminating the pathogenic. For example, damage of yin by heat should be treated by clearing away heat combined with nourishing yin.

C. Alternate application

a. Reinforcing the healthy prior to eliminating the pathogenic

It is applicable to syndromes of deficiency of healthy qi with excess of pathogenic qi, in which healthy qi cannot withstand attack. Though there is excess of pathogenic qi, healthy qi should be first reinforced by tonifying, as it is too weak to withstand attack. After healthy qi becomes strong enough to withstand attack, the pathogenic can be eliminated then. Take patients with the syndrome of helminthic accumulation for example. Since the spleen qi has already declined to extremes so that it cannot withstand parasiticides, healthy qi should be first reinforced by invigorating spleen and replenishing qi. When deficiency of the spleen is gradually relieved, measures should be taken to dispel helminthic accumulation then.

b. Eliminating the pathogenic prior to reinforcing the healthy

It is applicable to syndromes of excess of pathogenic qi with deficiency of healthy qi and, in which pathogenic qi needs eliminating urgently and healthy qi can still withstand attack. Though healthy qi is deficient, it can still withstand attack. So pathogenic qi should be first eliminated by purgation, and then regulating and tonifying can he taken up. Take blood deficiency caused by stagnant blood, metrorrhagia and metrostaxis for example. If stagnant blood is not removed, metrorrhagia and metrostaxis cannot be stopped and blood deficiency will worse. So, stagnant blood should be dispelled by activating blood and dispelling stasis and then measures should be taken to tonify and nourish blood.

Regulating Yin and Yang

The fundamental mechanism of disease is disharmony of yin and yang. Therefore, regulating yin and yang for the purpose of reestablishing coordination and balance is a cardinal therapeutic principle.

1. Reducing excess

It means to treat syndromes with preponderance of yin or yang by reducing excessive yin pathogens or yang pathogens. Preponderance of yang causes the syndrome of excess heat, and should be treated by "treating heat with cold",i. e. cold-cool drugs are used to clear away and purge yang heat, preponderance of yin causes the syndrome of excess cold, and should be treated by "treating cold with heat",i. e.warm-hot drugs are used to dispel yin cold.

2. Supplementing insufficiency

It means to treat syndromes with decline of yin or yang by supplementing insufficient yin or yang. Decline of yin or yang includes deficiency of yin, deficiency of yang and deficiency of both yin and yang. Therefore, treatment should be determined flexibly according to individual conditions.

A. Nourishing yin

It is applicable to yin deficiency. Since deficient, yin cannot restrict yang and yang becomes preponderant. As a result, a syndrome of deficiency-heat occurs, which should be treated by nourishing yin so as to restrict yang, i. e. "strengthening the governor of water to restrict hyperactivity of yang. "

B. Tonifying yang

It is applicable to yang deficiency. Since deficient, yang cannot restrict yin and yin becomes preponderant. As a result, a syndrome of deficiency-cold occurs, which should be treated by tonifying yang so as to restrict yin.i. e. "supplementing the source of fire to eliminate preponderance of yin".

C. Supplementing both yin and yang

It exactly means to both nourish yin and tonify yang, and is applicable to deficiency of both yin and yang. Yin deficiency should be treated by nourished yin, yang deficiency by tonifying yang, and deficiency of both yin and yang by supplementing both yin and yang. When this principle is applied to treatment, attention should be paid to differentiate what is primary from what is secondary and what is early from what is late, so that nourishing yin and tonifying yang can be taken up in order of importance.

Yang impairment involving yin is marked by deficiency of both yin and yang, with yang deficiency as the primary contradiction of disease. It should be treated by "treating yin for yang", namely tonifying yang supplemented by nourishing yin. Yin impairment involving yang is marked by deficiency of both yin and yang, with yin deficiency as the primary contradiction of disease. It should be treated by "treating yang for yin", namely nourishing yin supplemented by tonifying yang.

Moreover, due to the relativity of the implication of yin and yang, all pathological changes can be generalized by disharmony of yin and yang. Therefore, in a broad sense, the following therapeutic methods belong to the scope of regulating yin and yang, releasing superficies and relieving interior, emesis and purgation, raising the lucid and dropping the turbid, warming cold and clearing heat, reinforcing deficiency and reducing excess, regulating visceral functions, regulating qi and blood, etc.

Regulating qi and blood

Qi and blood are the essential substances for the maintenance of life activities and also the material basis of functional activities of various tissues and organs such as viscera and meridians. Disorders of qi and blood will involve the whole body, while pathological changes of any part of the body will cause disorders of qi and blood. Therefore, it is an important therapeutic principle.

1. Regulating qi

A. Tonifying qi

It is applicable to qi deficiency. Qi of the human body comes from innate qi, food nutrients and clear qi of nature, and is formed by qi transformation of the lungs, spleen, stomach and kidney. Innate defects, required malnutrition and the functional disorders of the lung, kidneys, spleen and stomach can all lead to qi deficiency. Therefore, tonifying qi is to tonify and replenish the kidney, spleen, stomach and lung. Since the spleen and stomach play a major role in the generation of required qi, tonifying qi attaches great importance to qi of the spleen and stomach.

B. Regulating qi movement

It refers to regulate the movements of qi, including ascending, descending, exiting and entering, applicable to syndromes caused by disorders of qi movement. For example, qi stagnation should be treated by promoting flow of qi, reversed flow of qi by driving qi downward, sinking of qi by raising qi, etc.

2. Harmonizing blood

A. Tonifying blood

It is applicable to syndromes of blood deficiency. Since blood originates from food nutrients and is generated by qi transformation of the spleen, stomach, heart, kidney, liver, etc. So tonifying blood is mainly to regulate and tonify functions of these viscera. And as the generative source of qi and blood, the spleen and stomach play a critical role in the generation of qi and blood. Consequently, tonifying blood attaches great importance to regulate and nourish the spleen and stomach.

B. Cooling blood

It is applicable to syndromes of blood heat. Blood heat can be caused by deficiency and excess as well as external contraction and internal injuries, clinically marked by fever, hemorrhage, upset, etc. Therefore, cooling blood should be flexibly used in clinical treatment. For example, high fever caused by blood heat should be treated by cooling blood and clearing heat; hemorrhage caused by blood heat should be treated by cooling blood to stop bleeding; disturbance of heart by blood heat should be treated by cooling blood to tranquilize mind.

C. Activating blood

It is applicable to syndromes of stagnant blood. Stagnant blood can be caused by various reasons, including blood cold, blood heat, qi deficiency, reversed flow of qi, yin deficiency, hemorrhage, excessive emotional stimulation, traumatic injuries, etc. Therefore, activating blood should be flexibly used in clinical treatment. For example, stagnant blood caused by blood cold should be treated by warming meridians and dispersing cold to promote blood circulation; stagnant blood caused by qi deficiency should be treated by tonifying qi and activating blood.

3. Regulating the relationship between qi and blood

Qi and blood are closely related to and complement each other. So pathologically, they usually affect each other. For example, qi disorders involve blood, blood disorders involve qi, etc. Therefore, the relationship between qi and blood should be regulated.

A. Regulating qi supplemented by regulating blood

Since qi generates blood, deficiency of both qi and blood, caused by insufficient generation of blood due to qi deficiency, should be treated by tonifying qi supplemented by tonifying blood. Since qi promotes the circulation of blood, blood stagnation caused by qi stagnation should be treated by promoting the flow of qi supplemented by activating blood and resolving stasis; stagnant blood, caused by failure of deficient qi, should be treated by tonifying qi supplemented by activating blood. Since qi governs blood, so hemorrhage caused by qi deficiency should be treated by tonifying qi supplemented by stopping bleeding with astringents.

B. Regulating blood supplemented by regulating qi

Since blood nourishes qi, qi deficiency resulted from blood deficiency should he treated by nourishing blood supplemented by tonifying qi; Since blood transports qi, deficiency of both qi and blood resulted from chronic hemorrhage should be treated by stopping bleeding and nourishing blood supplemented by tonifying qi. However, qi prostration after blood prostration resulted from hemorrhage should be treated first by replenishing qi and stopping bleeding, and then by tonifying blood and replenishing qi when the disease is somewhat relieved.

Treatment in accordance with seasonal conditions, local conditions and patient's individuality

It means that therapeutic principles should be determined according to seasonal, local and individual conditions, also known as "treatment in accordance with three factors". Traditional Chinese medicine holds that the occurrence, development and change of disease are influenced by various internal and external factors. Therefore, in clinical practice, seasonal climates, geographic environment and individual differences should be all taken into account, and individual differences should be all taken into account, and appropriate methods should be chosen according to specific conditions.

1. Treatment in accordance with seasonal conditions

It refers to that therapeutic principles should be determined according to features of seasonal climates.

Since seasonal variations of weather, from coolness and cold to warmness and heat, to a certain degree, influence physiology and pathology of the body, treatment and prescription should be different in different seasons. Different seasons, characterized by diverse features of climates, have different requirements for dosage as well as cold or hot nature of drugs. For example, in spring and summer when the weather changes from warm to hot and yang qi ascends, the interstices of the body become looser. During this period, even for external contraction of wind-cold, pungent-warm dispersing drugs, such as Ma Huang (Herba Ephedrae) and Gui Zhi (Ramulus Cinnamomi), should be used cautiously so as not to impair qi and yin due to excessive dispersion; in autumn and winter when the weather turns cold from cool and yin becomes preponderant with decline of yang, the interstices become tighter and yang qi retreats interiorly. So drugs of cool or cold nature, such as Shi Gao (Gypsum Fibrosum) and Bo He(Herba Menthae), should be used cautiously to avoid impairment of yang qi.

2. Treatment in accordance with local conditions

It refers to that therapeutic principles should be determined according to features of geographical environment.

Individuals in various geographic environments differ in constitutional features and pathological changes due to diverse climatic conditions and living habits. Accordingly, treatment and prescription should be suited to local conditions as well. For example, in the northwestern highlands of China, it is cold and dry, with scanty rainfall. So wind-cold and dryness are commonly seen and usually treated by pungent-moistening formula, while cold-cool-dry formula should be used with great care. In the southeastern coastal lowlands of China, it is hot and damp, with plentiful rainfall. So damp-heat is commonly seen and should be treated by heat clearing and damp-resolving drugs, while damp-inducing drugs of warm or hot nature should be used cautiously.

3. Treatment in accordance with patient's individuality

It refers to that therapeutic principles should be determined according to features of patient's age, sex, constitutions, living habits and occupations.

A. Age

Individuals of different ages are characterized by different physiological functions and pathological changes. Due to deficient qi and blood as well as decline of physiological functions, the aged people often suffer from deficiency syndrome or syndrome of deficiency-excess in complexity, which should be mainly treated by tonifying methods. Even when there are excess pathogens, drastic drugs; large dosage and long-term treatment are not advisable. As to infants, they are vigorous in physiological functions, but their qi and blood are not sufficient enough and their viscera are tender and delicate. Consequently, they are likely to be affected by cold or heat as well as deficiency or excess syndromes. Therefore, the small dosage of drugs is advisable, and drastic tonifying o purgation is contraindicated.

B. Gender

Man and woman have different physiological features. Especially, women have menstruation, leukorrhea, pregnancy and delivery, which all need special attention. For example, during pregnancy, drugs of drastic purgation, breaking stagnant blood, slipperiness, migration and toxicity should be contraindicated or used with great care. After labour, deficiency of qi and blood, breast-feeding and lochia should be taken into account.

C. Constitutions

Different types of constitutions have direct effect on the occurrence of disease, and produce different responses to medicinal treatment. Therefore, in clinical treatment, constitutional factors should be taken into account. For example, for the same disease, individuals with constitutions of yin deficiency and yang excess should be treated with great care by drugs of warm, hot, pungent and dry nature; those with constitutions of yang deficiency and yin excess should contraindicate drugs of cold, cool and fresh nature; those of strong constitutions, benefited from strong tolerance, can be treated by drastic drugs with large dosage; those of weak constitutions, owed to poor tolerance, should be treated by mild drugs with small dosage.

In addition, in diagnosis and treatment, attention should be also paid to psychological states, occupational features, working conditions and living environment, for they are all related to the occurrence of disease.