Dosages for individual herbs

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Theories and concepts in the composition of Chinese herbal formulas
Chinese herbs are not used singly in treatment, but in combinations known as herbal formulas. This is because herbal combinations have several advantages compared to the use of single herbs. First of all, herbal combinations may have wider applications than single herbs. For instance, when pathogenic heat accumulates in the Lung and Stomach, and the Qi of these two organs is deficient, a single herb can hardly treat this syndrome completely whereas a herbal combination can achieve an effective therapeutic result. Second, a herbal combination can reduce the side effects of individual herbs. Each single herb has its specific characteristics, which bring a unique effect to treatment, but these characteristics may also become a weak point. For example, Shu Di Huang ( Rehmanniae radix praeparata) is an excellent herb to tonify the blood and Kidney-essence but its cloying nature places an extra burden on the Stomach, which may impair its tonifying action. However, if it is used with Sha Ren ( Amomi xanthioidis fructus), which promotes Qi movement and removes any accumulation of dampness, this side effect can be reduced. Third, a herbal combination can have a much stronger effect than that of individual herbs, and may even induce a new effect. For example, Huang Qi ( Astragali radix) is able to tonify and raise the Spleen-Qi and increase muscular strength. Chai Hu ( Bupleuri radix) and Sheng Ma ( Cimicifugae rhizoma) have an ascending property but neither of them can tonify the Qi nor strengthen muscular contraction. However, if these three herbs are used together, the effect of raising the Qi and strengthening muscular contraction becomes much stronger. This combination can be used to treat weakness, heaviness of muscles and prolapse of internal organs due to Spleen-Qi deficiency.

1. Common types of herbal combination

Since a herbal combination has obvious advantages in treatment, the relationships between the herbs used in traditional Chinese medicine (TCM) have been carefully studied and certain types of relationship are identified. They are called the seven relations between herbs, e.g. mutual accentuation, mutual enhancement, mutual counteraction, mutual suppression, mutual antagonism, mutual incompatibility and single effect. Some of these are very useful in treatment, but some are harmful and therefore must be avoided.

1.1. Mutual accentuation (Xiang Xu B9780702031328000062/if1.jpg is missing)

In this type of combination, two herbs with similar functions are used together to increase the therapeutic effect, achieving a safer and more effective therapeutic result than the use of a larger dosage of a single herb. For instance, Jing Jie ( Schizonepetae herba) and Fang Feng ( Saposhnikoviae radix) can expel wind and release the exterior much more strongly when they are used together. Jin Yin Hua ( Lonicerae flos) and Lian Qiao ( Forsythiae fructus) can more effectively reduce heat-toxin if they are used together. Da Huang ( Rhei rhizoma) and Mang Xiao ( Natrii sulfas) can promote bowel movement to treat severe constipation more effectively and safely than the use of Da Huang ( Rhei rhizoma) alone.

1.2. Mutual enhancement (Xiang She B9780702031328000062/if2.jpg is missing)

This type of combination involves two herbs that have different functions. The first directly targets the pathological condition and the second increases the therapeutic effect of the first. For instance, Zhi Mu ( Anemarrhenae rhizoma) nourishes the Yin of the Kidney and clears heat in the Lower-Jiao, while Huang Bai ( Phellodendri cortex) reduces empty-heat in the Lower-Jiao and is therefore able to enhance Zhi Mu’s function of nourishing the Yin.
In addition, this type of combination is widely used to correct the side effects of a particular herb, to prolong the action of a herb in a steady way, to moderate the movement of Qi and to harmonize the internal organs. In this type of combination, the first herb treats the main disorder and its dosage and function are larger and stronger than those of the second herb. The second herb serves to reduce the side effects and to moderate the speed and the temperature of the first. For example, sweet Zhi Gan Cao ( Glycyrrhizae radix preparata) can moderate the speed of hot Fu Zi ( Aconiti radix lateralis preparata)* and can also reduce the harsh purging effect of Da Huang ( Rhei rhizoma).
Another example is when one wants to strengthen the Heart-Qi and treat restlessness and palpitations. Here Ren Shen ( Ginseng radix) is often selected as it directly tonifies Heart-Qi. Ren Shen is combined with a small amount of Wu Wei Zi ( Schisandrae fructus) which is very sour and has a stabilizing and binding ability. It can stabilize the Heart-Qi which Ren Shen generates. Moreover, when the Heart-Qi is weak, it may find it hard to accept strong tonifying action and Ren Shen used on its own may lead to restlessness and palpitations at the start of treatment and may further consume Heart-Qi. In this condition, Wu Wei Zi can reduce the harsh effects of Ren Shen and make its action more moderate and longer lasting.
There are many examples that illustrate the benefits of this type of herbal combination. Huang Lian ( Coptidis rhizoma) descends and clears fire from the Stomach, but it may also suppress Stomach-Qi and cause discomfort in the Stomach. If Sheng Ma ( Cimicifugae rhizoma) is prescribed at the same time, it can ascend and disperse the Stomach-Qi constraint and Stomach-fire, thereby reducing the side effects of Huang Lian.

1.3. Mutual counteraction (Xiang Wei B9780702031328000062/if3.jpg is missing)

In this combination, the characteristic side effects or toxicity of a single herb can be minimized or neutralized by another. This combination strategy is often used when processing harsh and toxic herbs. For example, the toxic effects of Ban Xia ( Pinelliae rhizoma) can be reduced by Sheng Jiang ( Zingiberis rhizoma recens).

1.4. Mutual suppression (Xiang Sha B9780702031328000062/if4.jpg is missing)

In this type of combination, the first herb suppresses or minimizes the toxicity of the second herb. For instance, Lü Dou ( Phaseoli radiati semen) can reduce the toxicity of Ba Dou ( Crotonis fructus)*, while Ge Hua ( Puerariae flos) can reduce the toxic effects of alcohol.

1.5. Mutual antagonism (Xiang Wu B9780702031328000062/if5.jpg is missing)

In this type of combination, some herbs can reduce the therapeutic effect of others. For instance, Lai Fu Zi ( Raphani semen) can reduce the ability of Ren Shen ( Ginseng radix) to tonify the Qi. This type of herbal combination and effect should be avoided in treatment. The Chinese medical tradition has identified 18 antagonistic substances:

• Liu Huang ( Sulfur)* antagonizes Po Xiao ( Glauberis sal)
• Shui Yin ( Hydrargyrum)* antagonizes Pi Shuang ( Arsenicum)*
• Lang Du ( Euphorbiae Fischerianae radix)* antagonizes Mi Tuo Seng ( Lithargyrum)*
• Ba Dou ( Crotonis fructus)* antagonizes Qian Niu Zi ( Pharbitidis semen)*
• Wu Tou ( Aconiti radix)* antagonizes Xi Jiao ( Rhinoceri cornu)**
• Ya Xiao ( Nitrum) antagonizes San Leng ( Sparganii rhizoma)
• Ding Xiang ( Caryophylli flos) antagonizes Yu Jin ( Curcumae radix)
• Ren Shen ( Ginseng radix) antagonizes Wu Ling Zhi ( Trogopterori faeces)
• Rou Gui ( Cinnamomi cassiae cortex) antagonizes Chi Shi Zhi ( Halloysitum rubrum).

1.6. Mutual incompatibility (Xiang Fan B9780702031328000062/if6.jpg is missing)

In this type of relationship, as soon as the two herbs are used together, a dangerous effect can arise so the use of this type of combination is absolutely forbidden. Traditionally there are 19 substances involved:

• Wu Tou ( Aconiti radix)* is incompatible with Chuan Bei Mu ( Fritillariae cirrhosae bulbus), Gua Lou ( Trichosanthis fructus), Ban Xia ( Pinelliae rhizoma), Bai Lian ( Ampelopsitis radix) and Bai Ji ( Bletillae tuber)**
• Li Lu ( Veratri nigri radix et rhizoma) is incompatible with Ren Shen ( Ginseng radix), Sha Shen – Bei Sha Shen ( Glehniae radix)/Nan Sha Shen ( Adenophorae radix), Ku Shen ( Sophorae flavescentis radix), Xuan Shen ( Scrophulariae radix), Dan Shen ( Salviae miltiorrhizae radix), Xi Xin ( Asari herba)*, Shao Yao – Chi Shao Yao ( Paeoniae radix rubra)/Bai Shao Yao ( Paeoniae radix lactiflora).

1.7. Single effect (Dan Xing B9780702031328000062/if7.jpg is missing)

This is a special pattern in herbal relationships. Some herbs can be used alone to treat a simple syndrome or to achieve special effects based on their characteristics. Some herbs can be used alone because they have reasonably balanced properties and functions. For instance, in critical conditions, Ren Shen ( Ginseng radix) can be used on its own in a large dosage to rescue the Yang and Qi from collapse. Dan Shen ( Salviae miltiorrhizae radix), which can cool the blood, clear heat and promote blood circulation, is often used alone in conditions where heat is consuming the Yin and blood, leading to blood stagnation. Dang Gui ( Angelicae sinensis radix) can also be used alone as it has a moderate action in promoting blood circulation and tonifying the blood.
Of the above seven types of relationship, those of mutual accentuation and mutual enhancement are commonly used in treatment; mutual counteraction and mutual suppression can also be used, especially to reduce herbs’ side effects or toxicity. The single herb effect is only used in a limited number of disorders; relations of mutual antagonism and mutual incompatibility should be avoided in treatment.
In addition to these relationships, there is another kind of relationship between herbs in treatment. In this type of combination, two herbs work as one unit although they have different properties and functions, and in this case they are equally important. Together they treat a condition with which a single herb would not be able to deal. For example, to treat warm and cold coexisting in one syndrome, where Yang and Qi deficiency generate cold while stagnation of Qi generates heat, the patient may, on the one hand, have a cold, weak and sensitive Stomach and prefer warm drinks and compresses; on the other hand, the patient may have a dry mouth with a bitter taste and heartburn. In this situation, the pungent and warm Ban Xia ( Pinelliae rhizoma) which can disperse cold is used with the bitter and cold Huang Qin ( Scutellariae radix) which can reduce the accumulated heat. Without this combination, it is almost impossible to treat this syndrome effectively. Another example is when one needs to regulate the Lung-Qi, clear heat and relieve shortness of breath. The pungent and hot Ma Huang ( Ephedrae herba)* is used to stimulate the Yang and disperse the Lung Qi; the sweet and cold Shi Gao ( Gypsum) is used to descend the Lung-Qi and clear the heat of the Lung. This combination can regulate the Qi and smooth the breath.
(See Figure I.1 on page 34.)

2. The process of formula composition

With this knowledge of herbal combinations, a herbal formula can be composed. The purpose of prescribing formulas in clinical practice is to achieve maximum therapeutic effect with minimum side effects. To practice traditional Chinese herbal medicine, practitioners are required to be able to compose formulas by themselves for treating different syndromes.
Composing a formula is a process where several conditions must be fulfilled. First, one must make a clear syndrome differentiation, establish the treatment principles, select treatment methods and figure out the most suitable strategies. One should then follow the model of formula structure, selecting appropriate herbs to play specific roles in the formula and ensuring that treatment strategies are fully expressed.

2.1. Syndrome differentiation

Clear and correct syndrome differentiation is very important for selecting a suitable treatment method and creating an effective formula. Detailed differentiation of a syndrome should include the following parts.

Principal syndrome and main symptoms

The principal syndrome where the main pathological development is identified manifests through a series of main symptoms. For example, the main symptoms indicating an exterior wind-cold syndrome are chills and fever, headache and generalized body pain. These result from the invasion of wind and cold at the superficial region of the body, the failure of the Defensive-Qi to spread, and obstruction in the blood circulation.

Secondary syndrome and secondary symptoms

A secondary syndrome develops from the principal syndrome and manifests in a series of secondary symptoms. When the principal syndrome is treated, the secondary syndrome may disappear as well. For example, in an exterior wind-cold syndrome, since the superficial region is obstructed, the Lung-Qi is unable to disperse so the nose may be blocked and there may be shortness of breath. As soon as the wind-cold is expelled from the superficial region of the body, the Lung-Qi obstruction disappears and the secondary symptoms disappear too.
A secondary syndrome might be a coexisting syndrome that is less important at the time of treatment. For example, in an acute condition of Liver-Yang ascending and generating Liver-wind, the patient may also have a syndrome of Spleen-Qi deficiency but this is less important for treatment in this acute condition.
Secondary symptoms are accompanying symptoms that are not key symptoms in terms of syndrome identification but they should still be treated seriously. For example, in an exterior wind-heat syndrome, although cough is not as important a symptom as sore throat in terms of syndrome identification, it should still be treated as it causes suffering to the patient.

Tongue and pulse

These are essential diagnostic methods for syndrome identification as well as for giving a prognosis regarding the development of and recovery from the disease. A practitioner can obtain objective information from these diagnostic procedures.

2.2. The treatment principle

The treatment principle takes the main syndrome in a complex condition as the target for treatment. In the process of treatment, the syndrome will change and the treatment principle will thus change too. For instance, in a syndrome of Liver-Yang ascending and generating Liver-wind, the treatment principle should be to intensively and quickly descend Liver-Yang and extinguish Liver-wind. Once the Liver-Yang has returned to its original place and the Liver-wind has disappeared, a syndrome of deficiency of Spleen-Qi and stagnation of Liver-Qi may then become the main syndrome. The treatment principle should change to that of spreading the Liver-Qi and strengthening the Spleen.

2.3. The structure of a formula

Following the treatment principle, which is established in accordance with the syndrome differentiation, a formula can be composed. A formula is neither a group of herbs that treat all symptoms nor a combination that only treats the main syndrome. It has a structure where herbs are organized in order to meet the needs of the treatment. The structure of a formula contains four parts, namely: the chief, the deputy, the assistant(s) and the envoy. Each of these has specific functions in the formula.

Chief (Zhu B9780702031328000062/if8.jpg is missing, Jun B9780702031328000062/if9.jpg is missing)

The chief is the ingredient that directly treats the principal syndrome, which is manifested by the main symptoms.
The chief can be one ingredient, but it can also be a herbal combination. Generally speaking, the chief has a relatively large dosage within the formula as a whole, and it enters the meridians where the pathological changes are manifest.

Deputy (Fu B9780702031328000062/if10.jpg is missing, Chen B9780702031328000062/if11.jpg is missing)

• The deputy is the ingredient that has the function of accentuating and enhancing the effect of the chief ingredient to treat the principal syndrome.
• The deputy serves as the main ingredient acting directly against a coexisting syndrome.
The deputy can be one herb, a herbal combination, or several groups of herbal combinations, according to the needs of treating the principal syndrome and the coexisting syndromes.

Assistant (Zuo B9780702031328000062/if12.jpg is missing)

• The assistant accentuates and enhances the therapeutic effect of the chief or deputy ingredients, or directly treats secondary symptoms. The ingredient that has this function can be considered a helping assistant.
• The assistant moderates or eliminates the toxicity or harsh properties of the chief or deputy ingredients. The ingredient that has this function can be considered a corrective assistant.
• The assistant has a function or a moving tendency which goes against the chief ingredient but which is helpful in fulfilling the therapeutic effect and which may be used in complicated and serious conditions. The ingredient that has this function can be considered a strategic assistant.
Since this role may require a range of actions, there are often several herbs or herbal combinations acting as assistants in any one herbal formula.

Envoy (Shi B9780702031328000062/if13.jpg is missing)

The envoy serves as a guide to bring the rest of the herbs into the meridian or region where the main pathological change exists, allowing their actions to focus on this specific region. In most cases, the chief carries out this function as it must enter the place where the pathological change is located.
The envoy harmonizes and integrates the actions of the other ingredients in order to balance the action, temperature, speed and direction of the formula.
(See Figure I.2 on page 34.)

2.4. Principles, methods and strategies of selecting appropriate herbs when composing a formula

In order to compose effective formulas, the principles, methods and strategies of selecting herbs are very important. They enable a practitioner to compose formulas to treat a variety of syndromes. The principles, methods and strategies introduced in each chapter of this book are abstracted from a large number of formulas, integrating the knowledge of single herbs, herbal combinations, syndrome differentiation, treatment methods and treatment sequence. They are the essential part of this book.
Before composing a formula, the relevant syndrome is first identified. The syndrome is analyzed and divided into the principal syndrome and the secondary syndrome, which are manifested in the main symptoms and the secondary symptoms, with specific signs on the tongue and the pulse. These are the first steps in selecting the appropriate herbs to fulfill different roles in the formula. Moreover, the syndrome analysis evaluates the development of the disorder of the internal organs with regard to the pathological change. This provides another clue to assist the selection of the herbs in the formula. For instance, if Liver-Qi stagnation is diagnosed, it follows that the Liver can easily attack the Spleen, so in the formula some herbs that strengthen the Spleen should be prescribed. Similarly, if the patient has a Yang constitution, the stagnation of Liver-Qi can quickly generate Liver-fire, so some herbs that prevent the generation of fire or prevent the heat becoming strong should be added as well. In a condition of excess heat in the Lung, one should be aware that strong fire can easily consume both the Yin and the Qi, so one should not only prescribe herbs to reduce fire, but also herbs that nourish the Yin and tonify the Qi.
Next, an appropriate treatment principle to treat the presenting syndrome is established. For example, to treat an excess heat syndrome in the Lung, the treatment principle is to reduce the heat, nourish the Yin, regulate the Lung-Qi and, at a later stage, strengthen the Lung-Qi.
As soon as a treatment principle is established, the composition plan and treatment strategies can be arranged. For instance, to treat the syndrome of excess heat in the Lung and Stomach, one would first prescribe herbs that have sweet-cold, bitter-cold or salty-cold properties, and which have the functions of clearing heat and reducing fire in the Lung and Stomach. Second, herbs that are sweet and cold and that can nourish body fluids and protect the Yin, which has been severely consumed by the excess heat, should be selected. Herbs that can tonify the Qi should be selected if the Qi is weakened severely by the heat. Herbs that moderate the actions of the harsh herbs in the formula, and reduce their side effects, should also be added.

3. Dosages for individual herbs

3.1. Standard dosages for individual herbs

Generally speaking, the most common dosage for most crude herbs in Chinese texts is about 3–9 g orally per day. Modern concentrated herbal powder is six times stronger than crude herb, thus the common dosage for most single herbs is 0.5–1.5 g per day. According to my own experience, this dosage can be reduced to 0.2–0.5 g. A list specifying the dosages for individual herbs can be found in Appendix I.

3.2. Exceptions

Minerals

Minerals can be used at 30 g per day in traditional decoctions. Examples are Shi Gao ( Gypsum), Ci Shi ( Magnetitum), Long Gu ( Mastodi fossilium ossis), Mu Li ( Ostrea concha), Zhen Zhu Mu ( Concha margaritifera usta), Shi Jue Ming ( Haliotidis concha) and Wa Leng Zi ( Arcae concha). If concentrated powder is prescribed, the dosage should be about 1–2 g.

Lightweight herbs

Herbs that are light in weight should be prescribed at lower dosages, 0.5–3 g for crude herbs and 0.1–0.5 g for concentrated powders. Examples are Tong Cao ( Tetrapanacis medulla), Deng Xin Cao ( Junci medulla), Ma Bo ( Lasiosphaera) and Chan Tui ( Cicadae periostracum).

Poisonous herbs

Dosages for all poisonous herbs should be learned by heart. Since the toxic dose varies for each individual, the therapeutic range for these herbs is small and only experienced doctors should prescribe them.
Poisonous herbs in reasonably common use are Fu Zi ( Aconiti radix lateralis preparata)*, Wu Tou ( Aconiti radix)*, Xi Xin ( Asari herba)*, Ma Huang ( Ephedrae herba)*, Yang Jin Hua ( Daturae flos)*, Lei Gong Teng ( Tripterygii wilfordii caulis)*, Wu Gong ( Scolopendra)*, Quan Xie ( Scorpio)*, Bai Hua She ( Agkistrodon acutus)*, Mang Chong ( Tabanus)*, Zhe Chong ( Eupolyphaga seu opisthoplatia)*, Shan Dou Gen ( Sophorae tonkinensis radix)*, Ban Xia ( Pinelliae rhizoma), Tian Nan Xing ( Arisaematis rhizoma), Bai Fu Zi ( Typhonii rhizoma praeparatum)*, Wei Ling Xian ( Clematidis radix), Xian Mao ( Curculinginis rhizoma), Wu Zhu Yu ( Evodiae fructus), Hua Jiao ( Zanthoxyli fructus) and Yuan Zhi ( Polygalae radix).
Poisonous substances that are suitable for special pathological situations but which are rarely used are Ku Lian Pi ( Meliae cortex), He Shi ( Carpesii fructus), Gua Di ( Pedicellus cucumeris), Li Lu ( Veratri nigri radix et rhizoma), Chang Shan ( Dichroae febrifugae radix), Gan Sui ( Euphorbiae kansui radix)*, Da B9780702031328000062/if15.jpg is missing ( Knoxiae radix)* Yuan Hua ( Genkwa flos)*, Shang Lu ( Phytolaccae radix), Qian Niu Zi ( Pharbitidis semen)*, Ba Dou ( Crotonis fructus)* and Zhu Sha ( Cinnabaris)*.

3.3. Variations from the normal dosage range

Bland herbs, which promote urination and leach out dampness, can be used in relatively large doses; these include Fu Ling ( Poria), Yi Yi Ren ( Coicis semen) and Che Qian Zi ( Plantaginis semen).
Tonifying herbs can also be used in relatively large doses; these include Huang Qi ( Astragali radix), Shu Di Huang ( Rehmanniae radix praeparata), Mai Men Dong ( Ophiopogonis radix) and Bai He ( Lilii bulbus).
Aromatic herbs that open the orifices, expel wind-heat or wind-cold and promote Qi movement should be used in relatively small doses; these include Bing Pian ( Borneol), Su He Xiang ( Styrax), Bo He ( Menthae herba), Chai Hu ( Bupleuri radix), Xin Yi ( Magnoliae flos), Bai Zhi ( Angelicae dahuricae radix), Mu Xiang ( Aucklandiae radix)** and Sha Ren ( Amomi xanthioidis fructus).
Herbs that are used alone should be prescribed in relatively large doses; when they are prescribed as part of a formula, the dosage should be smaller.

4. Dosage in herbal formulas

4.1. General principles

The dosages of herbs in a formula should follow the standard dosages of the individual herbs. However, dosages may be varied within the normal dosage range according to the position each herb occupies in the formula. Generally speaking, a relatively large dose of the chief herb(s) should be prescribed, whereas envoy herbs should be given at small dosages. The dosages of the deputies and the assistants depend on their number and the strength of the functions required of them. In a small formula (i.e. one that contains less than five herbs), the dosages should be relatively large. In a medium-sized formula (containing 9–12 herbs), medium-sized dosages should be used. In a large formula (containing more than 20 herbs), the dosages should be low.

4.2. Adjusting dosage to reflect the presenting syndrome

The dosages of the individual herbs in a formula should be varied according to the presenting syndrome. For instance, the usual dosage for Chai Hu ( Bupleuri radix) is 6–9 g per day. It is pungent and neutral, and can effectively ascend and spread the Liver-Qi. It is very often used as the chief herb in formulas to treat Liver-Qi stagnation. However, in situations where Liver-Qi stagnation is accompanied by blood deficiency, a smaller dosage of Chai Hu (e.g. 6 g), should be prescribed to ensure that its Qi dispersing effect does not consume or weaken the blood. If the presenting condition features Liver-Qi stagnation with Spleen-Qi deficiency and an accumulation of dampness in the Upper- and Middle-Jiao, Chai Hu should be prescribed at a relatively large dosage, such as 9 g, because it needs more strength to disperse in order to overcome the dampness. In a case with Liver-Qi stagnation, Liver-Yin deficiency and Liver-Yang rising, Chai Hu should be prescribed at a very low dose, such as 3 g, or even removed from the formula altogether to prevent its ascending property from exacerbating the tendency of Liver-Yang to rise.

4.3. Adjusting dosage during the course of the treatment

When treating acute diseases, or the active stage of chronic diseases, the dosages of herbs in a formula should be large. When the disorder is under control, the dosages should be reduced. Formulas that open the orifices, induce sweating, vigorously purge accumulation by promoting bowel movement and induce vomiting are used only once. Afterwards, the dosage must be adjusted according to the patient’s condition. For instance, to treat severe constipation due to severe obstruction of food, Qi, blood and fire-toxin in the abdomen, a vigorously purging formula should be given to eliminate accumulation. But only a single dose should be given. If the condition of the patient does not improve and the syndrome remains the same, this formula should be given again. As soon as the patient has a bowel movement, use of the formula should cease, and a gentle formula to regulate the Qi, moisten the intestines and protect the Spleen should be prescribed.
Formulas that contain strong herbs to treat acute and excess syndromes should not be used at high dosages for more than 4 weeks. These include formulas that:

• disperse the Lung-Qi
• disperse wind, cold and dampness
• strongly reduce heat-toxin
• purge and drain downward
• break up Qi stagnation
• remove congealed blood
• remove food stagnation
• sedate the Heart-shen and descend the Liver-Yang.
In treating chronic diseases, or after intensive treatment for acute disorders lasting 1–4 weeks, the herbs in a formula should be prescribed at lower dosages. Herbs that tonify or harmonize the functions of the internal organs should be added.
Intensive treatment can be repeated, according to the disease and the patient’s condition.
Gentle tonifying herbs can be used for months or even years at low doses to keep the patient’s condition stable, to strengthen the body’s resistance and to maintain a good health.
It is good to have breaks in long-term treatment of chronic disorders. The best time to do this is in the summer because summer-heat or damp-heat may weaken the function of the Spleen at this time, and the herbs may overburden the Spleen and cause digestive disorders.

4.4. Adjusting dosage to take account of the patient’s constitution and diet

Relatively large dosages can be prescribed for young people, people with good constitutions and people in good physical condition when they suffer from acute excess syndromes. Small dosages are prescribed for elderly people, people with weak constitutions and people who suffer from chronic diseases.
Foodstuffs and drinks possess warm or cold properties which may influence the action of herbs. Generally speaking, coffee, spices, mutton, liver, fat, oil and nuts can easily generate heat. Most fruit, vegetables and cold beverages have a cold nature and can bring cold into the body. Milk products and fat may generate phlegm. This should be taken into consideration when prescribing the herbs in a formula.

4.5. Adjusting dosage according to the patient’s age

The elderly

In elderly people, the Qi, blood and essence are no longer strong, the movement of Qi and the circulation of blood are not smooth, the digestion of food and the metabolism of water become slow, and the mood is often unstable. Consequently, herbs should be prescribed with extra care.
• Herbs should be prescribed at lower dosages within the normal range.
• Gentle tonifying herbs can be used at low dosages for a long period of time to strengthen the body’s resistance or to maintain good health.
• Tonifying herbs should initially be prescribed at low dosages because their cloying nature may cause indigestion. If all is well, the dosages may be gradually increased.
• Herbs that promote digestion, calm the mind and spread the Liver-Qi should be used in chronic disorders and when the patient is recovering from disease.

Children

Children have special physiological and pathological characteristics. As their internal organs, muscles and bones are delicate and their physiological functions are not fully developed, children become ill more easily than adults, and their diseases develop quickly. Therefore, the proper formula with suitable dosages of herbs should be given at the appropriate time.
The common daily dosage of individual herbs for children is as follows:

• infant: 1/10 of the adult dosage
• infant–1 year old: 1/6 of the adult dosage
• 1–2 years old: 1/4 of the adult dosage
• 2–4 years old: 1/3 of the adult dosage
• 4–6 years old: 1/2 of the adult dosage
• 6–14 years old: 2/3 of the adult dosage.
Note

• The adult dosage referred to here is the average adult dosage.
• The dosage given is for children with a normal weight and height for their age.
• The dosage can be varied within the normal range according to the disease and the patient’s constitution as well as the experience of the practitioner.

Children who are thin and weak

• Herbs should be given in dosages at the lower end of the normal dose range.
• Gentle herbs that tonify the Spleen and Kidney can be used at low dosages for a long period of time to support the child’s development.
• Tonifying herbs should initially be given at low doses, and then gradually increased, because their cloying nature may cause indigestion. Herbs that promote digestion should be prescribed at the same time.
• Herbs that calm the mind and spread the Liver-Qi should be used when treating stressed and sensitive children.

Obese children

• Dosage should be at the upper end of the normal dose range for children. It should not be the same as the dosage for an adult with the same weight.
• Use herbs that reduce phlegm, food stagnation and dampness. Herbs that tonify the Qi and activate the Qi movement can be used if necessary.
• Sport and a healthy diet should be recommended as part of the treatment.

4.6. Adjusting dosage according to the season and climate

In addition to the nature of the presenting disorder and the patient’s constitution, seasonal and climatic factors should also be considered.
In summer or in places with a warm dry climate, pungent, warm and bitter herbs should not be used at high doses because the pores of the body are not tightly closed and so the body fluid can easily be consumed by heat. This precaution relates to herbs that induce sweating, expel wind and cold, disperse the Lung-Qi, dry dampness and increase urination.
In winter or in cold places, cold, bitter, sour and astringent herbs should be prescribed in a relatively low dose. This precaution relates to herbs that clear heat, cool blood and drain downward. In humid places, herbs that transform dampness, activate the Qi movement and promote digestion should be used in relatively large doses because the herbs need extra strength to overcome the dampness.

4.7. Adjusting dosage to reflect particular times in the patient’s life

At times of great stress and high emotion, or of severe physical exertion and tiredness, the body becomes more sensitive, and herbs should be prescribed at lower dosages than normal. For instance, to treat severe tiredness due to Spleen-Qi and Heart-blood deficiency, herbs that tonify the Qi and blood should be used in the formula but their doses should be very low because any strong stimulation and tonification may cause further disorder in the body. If the patient suffers from insomnia and anxiety, formulas that calm the mind and sedate the Heart-spirit should be used first. At the time of menstruation, or if the patient has a bleeding wound, or immediately after surgery, herbs that promote Qi and blood should be prescribed at low dosages. If the patient is breast-feeding, herbs that are very warm or cold or that have harsh properties should not be used or only prescribed in low doses.

4.8. Adjusting dosage in light of the patient’s medical history

The dosages prescribed should take proper account of the patient’s medical history.
When patients suffer from chronic liver or kidney disease, the selection of the herbs and their dosages should be determined carefully to avoid placing an unnecessary workload on these weakened organs. At the same time, herbs that protect these organs and promote their function should also be included. For instance, acute or chronic liver diseases are mainly differentiated into a syndrome consisting of Spleen-Qi deficiency, damp-heat and heat-toxin accumulation, and herbs that treat this syndrome can be used. Chronic kidney diseases are mainly differentiated as Kidney-Yang and Spleen-Yang deficiency, dampness accumulation and heat-toxin in the blood. Herbs that treat this syndrome should be used in appropriate doses to help restore kidney function.
If a patient has recently undergone surgery, the Qi and blood need time to get strong again, so pungent, very warm or very cold herbs should only be used in low doses.
In situations where western drugs are used together with herbs and have similar functions, such as inducing sweating, stimulating blood circulation, removing congealed blood, purging the intestines and sedating the mind, the dosage of the drug or the herbs should be reduced.

5. Form of administration, preparation methods and their applications

5.1. Decoctions

Preparation

Place the dry herbal ingredients in an earthenware or stainless steel pot and add cold water until the water level is 3–4 cm above the herbs. Leave the herbs to soak in the water for at least 1 hour. Place the pot on the cooker and apply strong heat to bring it to the boil. Once the liquid is boiling, turn the heat down, simmer the herbs for 20 minutes, and then strain the decoction from the pot into a receptacle.
Pour another 200 ml of cold water onto the herbs in the pot and cook for a further 20 minutes. Strain the resulting liquid into the receptacle holding the first decoction, thus mixing the two decoctions together. The total liquid obtained should be about 200–250 ml. (Herbs that expel wind-cold or wind-heat should be cooked for 10 minutes less and tonifying herbs should be cooked for 10 minutes longer each time.)
Finally, divide the decoction into two or three doses and take these over the course of the day, warming each dose before drinking it.
Special preparation procedures

Because some herbs have particular properties, special procedures are required for their preparation.
Decocting first: Some substances are heavy and do not readily release their active ingredients into the decoction. They therefore need to be cooked for 30 minutes before adding the other herbs. Most of these ingredients are mineral substances, such as Ci Shi ( Magnetitum), Long Gu ( Mastodi fossilium ossis), Mu Li ( Ostrea concha), Shi Jue Ming ( Haliotidis concha) and Shi Gao ( Gypsum). Some toxic herbs, such as Fu Zi ( Aconiti radix lateralis preparata)* and Wu Tou ( Aconiti radix)*, should also be cooked for longer to reduce their toxicity.
Decocting later: Some aromatic or pungent herbs have active ingredients that will be destroyed by long cooking and these should be added to the pot 5 minutes before the end of cooking. Examples are Bo He ( Menthae herba), Qing Hao ( Artemisiae annuae herba), Huo Xiang ( Agastachis herba) and Xiang Ru ( Moslae herba). Also, in order to increase certain actions, some herbs are cooked for less time than normal. For instance, Da Huang ( Rhei rhizoma) can be cooked for a shorter time to increase its purgative action.
Some rare, expensive herbs, such as Ren Shen ( Ginseng radix), should be prepared separately. Herbs that are traditionally used in powder form should be added to the prepared decoction without cooking; an example is San Qi ( Notoginseng radix) powder. Gels and syrups such as E Jiao ( Asini corii colla), Yi Tang ( Maltose), honey and egg yolks, should be dissolved in the prepared decoction without cooking.

Applications

Decoction is the most common form of administration of Chinese herbal medicine. Decoctions are usually taken orally. They can be absorbed quickly and have the strongest action of all of the traditional types of preparation.
Formulas can be varied according to clinical need. The decoction method is used particularly for serious and acute conditions. Decoctions can also be used topically as herbal baths for the whole body or for the affected regions of the body.
Decoctions do, however, have some obvious drawbacks. They need a reasonable amount of time to prepare, especially in chronic diseases; they do not always taste pleasant; they are not easy to transport or to store. Nowadays, some herbal pharmacies have made some improvements in this respect, offering to cook decoctions for their patients and delivering the herbal medicine in sealed vacuum-packed bags that may be stored in a refrigerator for a few days.

5.2. Powders

Preparation

The dry raw herbal ingredients are ground into coarse or fine powders. Coarsely ground powders can be prepared in the same way as decoctions, though they require a shorter cooking time. Finely ground powders can be prepared by simply adding boiling water at the time of administration. Some fine powders can be applied topically for skin disorders, muscle strains and wounds.

Applications

Powders can be used in small dosages. They are easy to prepare, administer, transport and store. Powders are less wasteful than decoctions. Their main drawback is that their action is not as strong as decoctions. They are often used for sub-acute, chronic and mild cases.

5.3. Pills

Preparation

The dry raw herbs are ground into powder and are mixed either with water or with a viscous medium and shaped into pills. These may be of different sizes, depending on the practitioner’s specification.
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