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Chapter 1 General
Introduction of Herbology Section 1 Concepts and Origin of
Chinese Herbology
l. Concepts of Chinese Herbs
Chinese Herbs: The traditional Chinese herbs are of two major characteristics, most of
which are produced in China; and they are clinically used to treat diseases according to
the basic theory of traditional Chinese medicine and herbology. Chinese herbs reflect
traditional cultural features in the Chinese history in certain aspects.
Herbology: The herbology, an important component part of the traditional Chinese medicine,
is a special subject for studying the theory on properties of Chinese herbs, their
collection, preparation, effects, dosage and administration.
2. The Origin and
Development of Chinese Herbology
Chinese herbs originated from productive and medical practice by the laboring people in
ancient China. The record of "Shen Nong tasting a hundred herbs came across 70 toxic
substances in a single day'' is a vivid description of the discovery and development of
Chinese herbs by the laboring people in ancient China at enormous costs in the struggle
against diseases.
As early as the primitive times, while looking for food, mankind accidentally discovered
that some plants could alleviate or eliminate sufferings from diseases. Since then, people
have been actively looking for herbs.
In remote antiquity when written languages were not invented, the knowledge about herbs
could only be disseminated and accumulated generation by generation in spoken languages.
After the invention of written languages, the knowledge about herbs closely related to
birth, senility, illness and death of people was naturally recorded in written languages.
Medicinal wine was recorded with inscriptions on bones or tortoise shells in the Shang
Dynasty. Herbs were also recorded in early historical books.
With the increase in Chinese herbs, the development of their practical use and the
research into theory on their properties, special books on Chinese herbs were published.
In the history of the development of Chinese books, there were five herbal classic,
namely, Shen Nong's Herbal Classic, Variorum of Shen Nong's Herbal, The Newly Revised
Herbology, Classic Classified Herbology for Emergency, Compendium of Herbology, and
Supplement to the Compendium of Herbology. Among them, Compendium of Herbology has a
relatively enormous influence in the world.
Section
2 Collection and Preparation of Herbs
Part 1 Collection of
Herbs
Amount of active ingredients in medicinal parts of animals or plants vary from time to
time during their growth, which directly influences their qualities and curative effects.
Therefore, it is important to collect in good time when the contents of active ingredients
in medicinal parts reach the peak level. The time for collecting different medicinal parts
of plants can be summed up as follows:
1. Whole plants, stems and leaves are mostly collected when plants are in full bloom or in
early blossom either by cutting off their parts above the ground or by pulling up whole
plants with their roots. Seedlings or withered leaves are also used in some herbs, such as
oriental wormwood and mulberry leaf.
2. Flowers are generally collected in bud or in early blossom in order to avoid dispersion
of their fragrant smell and shedding of their petals. Pollen ar6 collected in full blossom
3. Fruits and seeds are mostly collected when they are ripe. Only a few of fruits are
collected when they are unripe, such as black plum, green tangerine orange peel and unripe
bitter orange. Some kinds of seeds easily shed when they are full ripen. Therefore, these
seeds should be collected when they are just nature.
4. Roots and rhizomes are mostly collected in early spring when plants have not sprouted
or in late autumn when the stem and leaves start withering. At that time, nutrients stored
in roots and rhizomes active ingredients are highest con tents. A small number of herbs
can be collected in summer, such as pinellia tuber and corydalis tuber.
5. Bark should be collected in spring and summer when it is thick with adequate fluid and
nutrients and easily stripped off. Root-bark should be collected in autumn, such as moutan
root-bark and wolfberry root-bark.
Part 2 Preparation of
Herbs
Herbs should be processed before using or making into various forms. Because most Chinese
herbs are used unprepared, besides general handling, quite a few should be specifically
processed to meet demands for their clinical use. Preparation, a traditional Chinese
pharmaceutical technology, was formed in a long history of practice with its complete
theoretical system and strict technique.
1. Aims of Preparation
High effects, low toxicity and convenience for use are the main aims of preparing Chinese
herbs.
1.1. To enhance curative effects
For example: corydalis tuber can obviously strengthen its analgesic effect by stir-baking
with vinegar; ephedra can strengthen the effects of alleviating cough, and relieving
asthma by stir-baking with honey; and eucommia bark can strengthen the effects of calming
the liver and reducing blood pressure by stir-baking with salt.
1.2. To reduce toxic effects
Some extremely toxic should not be used orally without preparation for reducing their
toxicity. For example: defatted powder of croton seed, kansui root and knoxia root boiled
with vinegar, Sichuan aconite root and wild aconite root boiled for a long time, and
pinellia tuber and arisaema tuber decocted with ginger and alum can all reduce their toxic
effects.
1.3. To change properties of herbs and expand their uses
Appropriate preparation can change cold or hot nature and augment effects of herbs. For
example, dried rehmannia root, being cold in nature for removing heat from blood to stop
bleeding, can be made into prepared rehmannia root for warming and tonifying essence and
blood. Prepared arisaema being warm and dry in nature for resolving cold phlegm, expelling
wind and alleviating spasm, can he made into biled arisaema with cool and moist nature for
removing heat, resoling phlegm, expelling wind and arresting convulsion. Fleece-flower
root with its main effects of treating malaria and loosing the bowels can be made into
prepared fleece flower root with its special effects of tonifying the liver and kidney and
nourishing essence and blood.
In addition, through preparation, herbs become easy to use and store. Also, the abnormal
flavor and some un-beneficial ingredients are removed.
2. Methods for
Preparation
Methods for preparation of Chinese herbs include purification, preparation with water,
preparation with fire and preparation with both water and fire. Methods for preparation of
Chinese herbs are closely related to their clinical usage;
2.1. Stir-baking
Herbs are put into a pot over a fire, continually stir-baked to a certain extent and taken
out. According to extent of heating, herbs can be stir-baked yellow in color, stir-baked
charred or stir-baked carbonized. To be stir-baked yellow or stir-baked charred can
moderate herbs' properties or strengthen the effect of invigorating the spleen; and to be
stir-baked carbonized can strengthen the effects of stopping bleeding and arresting
diarrhea.
2.2. Stir-baking with auxiliary fluid
The common auxiliary fluid includes wine, vinegar, and honey, saline and ginger juice.
Herbs stir-baked with auxiliary fluid can strengthen effects, reduce toxicity and remove
abnormal flavor. For example: Chinese angelica root stir-baked with wine can strengthen
the effects of promoting circulation of blood; corydalis tuber stir-baked with vinegar can
strengthen its analgesic effect; and kansui root stir-baked with vinegar can reduce
toxicity. In addition, herbs stir-baked with other auxiliary materials including sand and
talc powder can make them crispy and en able their active ingredients to be easily
decocted out, such as pangolin scales, stir-baked with sand and hedgehog skin stir-baked
with talc powder.
2.3. Calcination.
Herbs are directly or indirectly calcined over a fierce fire to make them crispy for
easily crushing or carbonized. Most of the solid and hard mineral herbs or shells are
directly calcined, such as dragon's bone and oyster shell. Carbonize6 palm and carbonized
hair are made by means of calcination in a sealed refractory vessel.
2.4. Roasting
Wrapped in moistened paper or flour paste, herbs are heated in smoldering cinder or
roasted in a oven until the coating becomes charred in order to remove oil from herbs or
to moderate their properties, such as roasted aucklandia root roasted ginger and roasted
nutmeg.
2.5. Steaming
Herbs are steamed solely or with auxiliary materials to change their proper ties,
strengthen their potency and reduce their toxic effects.
2.6. Boiling
Herbs are boiled in water and auxiliary materials to reduce their toxicity, such as genkwa
flower boiled with vinegar, and Sichuan aconite root boiled with bean curd.
2.7. Water-refining
Mineral herbs insoluble in water are crushed, put in a mortar, ground with water into fine
powder in suspension, then poured into a vessel for precipitation and dried, such as
wet-refined cinnabar then and water-refined talc.
In addition, there are fermentation, germination, frosting and many other methods for
preparation, such as medicated leaven, germinated barley and defatted powder of croton
seed.
Section
3 Theory on Herb Properties
Diseases are caused by pathogenic
factors, which affect the human body, resulting in dysfunction of the internal organs and
in hyperactivity or hypo-activity of yin, yang, qi and blood. Herbs are used to eliminate
pathogenic factors restore normal function of the internal organs and rectify
hyperactivity or hypo-activity of Yin, Yang, qi and blood, enable the body to recover from
illness.
Curative effects of herbs come from their polarizing properties. Rectification of
deviation by polarity is the essence of their curative effects. The theory on herb
properties and the law governing applications are pharmacology of Chinese herbs, including
four natures and five flavors, effects of lifting, lowering, floating or sinking, meridian
tropism and toxicity.
Part 1 Four Natures and
Five Flavors
Four natures and five flavors are the main contents of the theory on herb properties.
Natures and flavors of herbs are the first principle of all indicated in books on
herbology of all ages.
1. Four Natures
1.1. Concept of four natures
Four natures are cold, hot, warm and cool natures of herbs. Cold and cool natures are
different in essence form and antagonistic against warm and hot natures, forming the two
major properties. Cold nature is the same in essence as but, stronger than cool nature;
and hot nature is the same in essence as but stronger than warm nature.
1.2. Determination of four natures
Four natures of herbs are determined by their curative effects on cold and heat syndromes.
For example, patients with extreme heat, extreme thirst and energetic pulse, belonging to
heat syndrome of excess type, are treated with gypsum anemarrhena rhizome and other herbs.
If these heat symptoms are alleviated or eliminated, gypsum and anemarrhena rhizome should
belong to cold nature. Warm and hot natures of herbs are determined according to the same
principle.
1.3. Effects of four natures
In general, warm and hot herbs have the effects of warming and clearing the meridians,
warming the interior to disperse cold, supplementing fire to support yang, warming yang to
induce diuresis, and recuperating depleted Yang to rescue patients from collapse. Cold and
cool herbs have the effects of clearing heat to purge fire, removing heat from blood to
eliminate toxicity, purging heat to relax the bowels, inducing diuresis to treat
stranguria, and removing heat from the heart and liver.
"To treat cold syndrome with hot, and to treat heat syndrome with cold herbs'' is the
basic principle of using Chinese herbs. That is to say, warm and hot herbs are used to
treat cold syndrome, and cold and cool herbs are used to treat heat syndrome. In addition,
neutral herbs, such as liquorice, which has mild effects without obvious cold or hot
properties, can be used for both cold and heat syndromes.
2. Five Flavors
2.1. Concept of five flavors
Five flavors are pungent, sweet, sour, bitter and salty tastes of herbs, representing
their different effects. In addition, tasteless and puckery flavors still belong to five
tastes.
2.2. Determination of five flavors Five flavors are determined by actual tasting and
experience of clinical applications. Therefore, five flavors as a theory of herb
properties are far beyond the concept of tasting sensations but closely linked to effects
of herbs. That is the reason why flavors recorded in books on herbology are sometimes
different from actual tasting sensations.
2.3. Effects of five flavors are
briefly described as follows:
Pungent flavor herb has the effects of inducing diaphoresis, promoting
flow of qi and blood circulation. Pungent herbs include ephedra, purple perilla,
aucklandia root, cyperus tuber and green tangerine orange peel as well as chuanxiong
rhizome, Chinese angelica root and safflower, etc.
Sweet flavor herb has the effects of tonification, relieving spasm and
gentling other herbs, including astragalus root, prepared rehmannia root and polise
antler, White peony root, liquorice and malt extract as well as liquorice and Chinese
date.
Sour flavor herb has the astringent effect of suppressing sweating,
arresting bleeding, relieving diarrhea and controlling nocturnal emission. Sour herbs
include white peony root and schisandra fruit, dogwood fruit, black plum and Chinese gall
etc.
Bitter flavor herb has the effects of eliminating dampness, lowering
rebellious qi, purging heat and relaxing the bowels, such as apricot kernel and lepidium
seed, pinellia tuber and tangerine peel etc.
Salty flavor herb has the effects of softening and resolving hard lumps
to treat scrofula, subcutaneous nodule, mass in the abdomen, and other pathologically
formations, such as seaweed, oyster shell, fresh water turtle shell and eupolyphaga. In
addition, it is said that "salty herbs act on blood'' and "salty herbs act on
the kidney''. Therefore, some herbs with the effects of removing heat from blood and
tonifying the kidney taste salty.
In addition, tasteless flavor belongs to sweet with the effect of inducing diuresis to
remove dampness. Tasteless herbs include poria and lophatherum. Puckery flavor belong to
sour has the effect of astringency. Puckery herbs include dragon's bone and cuttlefish
bone.
Natures and flavors reflect properties and the principle of applications in limited
aspects. Therefore, only by combining natures with flavors, can the properties be
comprehensively grasped. For example, both scutellaria root and dried rehmannia root are
cold with the effect of clearing heat. However, scutellaria root, bitter in taste and cold
in nature for clearing heat and dampness, is indicated for damp-heat syndrome; while dried
rehmannia root, sweet in flavor and cold in nature for clearing heat and nourishing yin,
is indicated for yin deficiency and interior heat syndrome. All the herbs for relieving
exterior syndrome belong to pungent flavor. However, herbs, pungent in flavor and warm in
nature for relieving exterior syndrome, are indicated for wind-cold type of common cold;
while herbs, pungent in flavor and cool in nature for relieving exterior syndrome, are
indicated for wind-heat type of common cold. It can thus be seen that natures and flavors
are inseparably linked to each other.
Part 2 Effects of
Lifting, Lowering, Floating and Sinking
Lifting, lowering, floating and sinking refer to curative effects of herbs
relative to the tendency of illness. Only by grasping lifting, lowering, floating and
sinking effects of herbs and according to different causes and states of illness, can
physicians correctly use herbs to eliminate pathogenic factors, restore Qi and purge heat,
enable patients to recover from illness.
The tendency of disease development can be downward, upward, inward or outward. For
example, downward chronic diarrhea with proctoptosis, upward vomiting with hiccup, inward
exopathy with anhidrosis, and outward spontaneous perspiration with night sweating, are
all of obvious tendency of illness. Herbs for the above-mentioned syndromes
correspondingly have lifting, lowering, floating and sinking effects. For example,
astragalus root for diarrhea with proctoptosis has lifting effect; pinellia tuber for
vomiting with hiccup has lowering effect; ephedra for inducing sweating and dispel
exogenous pathogenic factors has floating effect; and oyster shell for astringency and
hidroschesis has sinking effect.
Lifting is the opposite of lowering; and floating is the opposite of sinking. Lifting
means ascending and elevating; lowering means moving downward and lowering the adverse
flow of Qi; floating is moving outward and dispersing; and sinking is descending and
removing water retention and inducing diuresis. In generally, properties of lifting upward
and floating outward have the effects of lifting Yang and arresting diarrhea, inducing
sweat and dispelling exogenous pathogenic factors, promoting eruption and inducing
vomiting, and may be indicated for deficiency of Qi and sinking of Qi of middle jiao.
Properties of Sinking inward and lowering downward have the effects of calming the liver,
removing heat from the lung, arresting vomiting, relieving asthma, easing the bowels, and
are indicated for hyperactivity of the liver-yang, flaring up of the heart-fire, reversed
flow of Qi in the lung and stomach, etc..
Lifting, lowering, floating and sinking effects of herbs are apparently linked to their
natures and flavors. Generally, pungent, sweet, warm and hot herbs mostly have lifting and
floating effects; sour, bitter, salty and cold herbs mostly have sinking and lowering
effects; flowers and leaves being light mostly have lifting and floating effects; and
minerals and shells being heavy mostly have sinking and lowering effects. However, there
are some exceptions.
In addition, lifting, lowering, floating and sinking effects of herb are also linked to
preparation, compatibility and other factors.
Part 3 Meridian Tropism
Herbs have strong affinity to internal organs and meridians. Meridian tropism means what
area the herb acts on. A remedy used to treat diseases of one meridian or several
meridians is called acting on the meridian or the meridians.
The theoretical basis for meridian tropism of herbs is the theory of zang-fu, and the
basis for practice is that the curative effects of meridians and collateral play the role
physiologically of linking various organs of the human body from exterior to interior.
Therefore, exterior syndrome influences the internal organs, and interior syndrome can be
reflected on the exterior. Through synthesis and analysis of the 4ata gained with the four
methods of diagnosis, the meridians in the internal organs with pathologic change can be
determined. Through the curative effects of a herb, what meridians the herb acts on can be
determined. For example, anxiety and insomnia, sore in the mouth and on the tongue, and
difficulty and pain in urination with dark yellow urine belong to excessive heat in the
heart meridian. Coptis root, lophatherum and fiveleaf akebia used to treat the syndrome
certainly act on the heart meridian.
The theory on meridian tropism in combination with therapeutic effects enables beginners
to grasp properties and practitioners to choose herbs in term of meridians in clinical
practice. For example, although scutellaria root, coptis root and phellodendron bark have
the same effects of purging heat and fire, they act on different meridians: scutellaria
root on the lung meridian, coptis root on the heart meridian, and phellodendron bark on
the kidney meridian. Therefore, scutel laria root is for cough due to the lungheat, coptis
root is for excessive heat in the heart and stomach, and phellodendron bark is for
hyperactivity of the ministerial fire.
Meridian tropism of herbs is inseparably linked to their four natures and five flavors as
well as lifting, lowering, floating and sinking effects. Remedies acting on the same
meridian can have different natures and flavors as well as quite different effects of
lifting and lowering. For example, although ephedra, dried ginger, scutellaria root and
dangshen act on the same lung meridian and are used to treat cough. Ephedra being pungent
and warm for facilitating the flow of the lung-qi to relieve asthma is used to treat cough
and asthma due to wind-cold dried ginger being pungent and hot for warming the lung to
reduce watery phlegm is used to treat cough and asthma due to cold-phlegm. Scutellaria
root being bitter and cold for removing heat from the lung is used to treat cough due to
lung-heat; and dangshen being sweet and neutral for supplementing the lung-qi is used to
treat chronic cough due to deficiency of the lung. Therefore, meridian tropism should be
comprehensively understood in combination with four natures and five flavors as well as
lifting, lowering, floating and sinking effects.
Part 4 Toxicity
Toxicity is referred to as harmful effects or toxic effects of herbs on the human body.
Attention should be paid to this problem in grasping herb properties of remedies.
Poisonous is different in their toxic effects. Therefore, herbs are distinguishably marked
by "slightly toxic'' or "extremely toxic'' in books on herbology of all ages. In
general, the toxic dose of a poisonous herb is close to its therapeutic dose with a
relatively small safety coefficient in its clinical use. If used improperly, a poisonous
remedy could cause severe damage to tissues and organs of the human body and even lead to
death. Therefore, when using a toxic remedy, an extremely toxic one, in order to guarantee
its safety dose, physicians should pay attention to the following points:
1. The dose of a poisonous herb should be strictly controlled.
An excessive dose is one of the main causes for intoxication of Chinese herbs. Therefore,
when using a toxic herb, physicians should strictly control its dose based on the
patient's age, constitution and the state of illness, and stop using it before going too
far. Toxic herbs should not be taken in an excessive dose or for a long time in order to
avoid excessive or accumulative intoxication of Chinese herbs.
2. Attention should be paid to use the toxic herbs correctly.
The key point to preventing intoxication of herbs is to use different herbs in different
way. Some toxic herbs should be taken in pill or powder but not in decoction; some should
be externally applied but not be orally taken; and some should be decocted for a long
time. Intoxication is often clinically caused by the improper use of a toxic herb. For
example, intoxication of Sichuan aconite root or prepared aconite root is mainly
attributed to inadequate decoction.
3. Preparation technique should be followed
One of the objects of preparation is to reduce or eliminate the toxic effects of 4rugs.
Therefore, strict technology of preparation and scientific standard of quality are
important guarantee for safe use of Chinese herbs in clinical practice.
In addition, specific attention should be paid to appropriate compatibility and avoiding
incompatibility.
Everything has its duality, and so has herb toxicity. The therapy of attacking toxicity
with poisonous remedies is often used to treat scrofula, malignant lump and tumor.
Section 4 Applications of Chinese Herbs
Attention should be paid to the
clinical use of Chinese herbs, including compatibility, contraindication, dosage and
administration.
1. Compatibility
Compatibility of herbs means the combined use of more than one herb according to treatment
needs.
The pathogenesis and development of illness are often complicate and changeable with
manifestations that deficiency and excess syndromes are simultaneously seen, cold
alternates with heat, and several diseases coexist. It is difficult for various symptoms
to be treated with a single herb. Therefore, appropriate compatibility, a main method of
the clinical use, can enhance their curative effects, expand the scope of their
applications, reduce their toxic effects, to suit the complicate state of illness.
Predecessors summarized six kinds of variations in herb compatibility, which plus that
being used alone without combination are called "seven different combination"
Single Remedy Alone: A single herb can be used to cure a disease. For example, Qingjin
Powder made from scutellaria root alone can be used to cure hemoptysis due to lung-heat.
Synergism: Herbs with similar effects used together can strengthen their curative effects.
For example, atractylodes rhizome and white atractylodes rhizome used together can
strengthen the effects of removing dampness and tonifying the spleen.
Assisting: When a main herb is used in combination with another auxiliary herb, the
auxiliary herb can strengthen the effect of the main herb. For example, poria can
strengthen the effects of astragalus root to strengthen the spleen and induce diuresis.
Their combination is called poria assisting astragalus root.
Restraint and detoxication: Restraint and detoxication are two aspects of one combination.
For example, fresh ginger can detoxify pinellia tuber. Their combination is called
pinellia tuber 6eing restrained by fresh ginger and fresh ginger detoxifying pinellia
tuber.
Antagonism: Herbs used together can reduce their curative effects. For example, when used
together, radish seed can weaken the effect of ginseng to supplement Qi.
Increasing Toxicity: Herbs used together can strengthen their toxic effects or produce new
toxicity, such as herbs in "eighteen incompatible medicaments''. Among the
above-mentioned compatibility, synergism and assisting should he fully used in clinical
practice to enhance curative effects; restraint and detoxication can be used to detoxify
poisonous herbs; and inhibition and increasing toxicity, belonging to incompatibility of
herbs, should be prevented from reducing curative effects or producing toxic reactions.
2. Contraindications
Herbs have their duality of curative effects and toxic effects. To use their curative
effects and avoid their toxic side effects are the basic principle for making up a
prescription. To avoid toxic effects is called contraindications, including in
compatibility of herbs and contraindication in pregnancy.
1.l. Incompatibility of Herbs:
Antagonism and increasing toxicity belong to contraindication. Incompatible 4rugs are
differently recorded in books on herbology of all ages and general lyrecognized in later
ages as "eighteen incompatible medicaments" and "nineteen medicaments of
mutually increasing toxicity'' which have great influence. In "eighteen incompatible
medicaments'' it says that: Sichuan aconite root is incompatible with pinellia tuber,
trichosanthes fruit, fritillary bulb, ampelopsis root and heacintbletilla; liquorice is
incompatible with seaweed, knoxia root, kansui root and genkwa flower; and veratrum root
is incompatible with ginseng, ladybell root, red sage root, scrophularia root, flavescent
sophora root, asarum herb and peony root. In "nineteen medicaments of mutually
increasing toxicity'' it says that: sulphur is antagonistic to crude mirabilite; mercury
to white arsenic; langdu root to litharge; croton seed to morning glory seed; cloves to
curcuma root; Sichuan aconite root and wild aconite root to rhinoceros horn; crystalized
mirabilite to burreed tuber; cinnamon bark to red halloysiie; and ginseng to trogopterus
dung. "Eighteen incompatible medicaments'' and "nineteen medicaments of mutually
increasing toxicity'' are recorded in books on herbology of all ages. Chinese Pharmacopeia
stipulates that incompatible herbs should not be used together. However, judged by actual
conditions, either ancient use or modern researches of Chinese herbs, there has been no
unified recognition on whether incompatible herbs can be used together or not. This
problem needs further clinical and experimental studies. At present, it will be better to
not use Chinese herbs together blindly.
1.2. Contraindications in Pregnancy:
Some herbs can damage the primordial Qi of fetus and even cause mis-carriage. Therefore,
women in pregnancy should be careful to use pungent and dry herbs with the effects of
relieving Qi and blood stasis, such as unripened bitter orange, peach kernel, rhubarb,
prepared aconite root and Chinese cassia bark. And they should be prohibited to use herbs
with strong toxicity or drastic effect, such as croton seed, kansui root, nux-vomica seed
and burreed tuber.
Contraindicated herbs should absolutely be prohibited; and carefully used herbs should not
be used unless obliged and safety is guaranteed.
In addition, there are contra-syndromes for herb applications and food taboo under which
patients should be prohibited to eat certain food during the herb taking period.
3. Dosage
The dosage indicated in this book refers to the amount of a dry raw herb in a decoction
orally taken by an adult per day.
Whether the dosage of an herb is proper or not directly influences its curative effect and
safety use. For example, it is difficult for small dosage to cure severe illness; and in
light illness the vital qi is prone to be damaged. The excessive dosage is one of the
common causes for intoxication of Chinese herbs.
Therefore, reasonable dosage is important. How to determine the dosage of herbs is related
to the following factors:
3.1. Properties: Neutral, heavy and non-toxic herbs (minerals and shells) should be used
in large dosage; drastic, light and toxic herbs should be used in small dosage. In
addition, some rare and expensive herbs, such as rhinoceros horn, cow bezoare and musk,
should be used in small dosage.
3.2. State of illness, Age and Constitution of the Patients:
In general, large dosage should be used for the patients with acute and heavy illness; and
small dosage for the patients with mild and light illness. For old and weak patients,
tonifying herbs should be used in large dosage; and for eliminating pathogenic factors in
small dosage.
3.3. Compatibility and Combination:
A single herb should be used in large dosage; and herbs in a complex prescription in small
dosage. Herbs in decoction should be used in larger dosage than in pill and in powder.
The dosage of Chinese herbs is calculated mainly in weight. In the past, an obsolete
system of weight was used in China with 1 Jin equal to 16 Liang and 1 Liang equal to 10
Qian. At present, the metric system of weight has been introduced with gram as the unit.
The obsolete system of weight can be approximately converted into the metric system of
weight: 1 Liang is equal to 30 grams; 1 Qian is equal to 10 grams; and 1 Fen is equal to
0.3 gram. For children over 6 months and under 5 years old, herbs can be used in a half
and a quarter of an adult dosage respectively. Smaller dosage should be used for babies
and infants.
4. Administration
The administration of Chinese herbs mainly refers to the methods of making a decoction,
points for attention and specific methods of making a decoction for some herbs.
4.1. Methods of Making a Decoction: It is appropriate to use an earthenware pot for making
a decoction. Before decocted, herbs should be soaked in cold water in the pot for half an
hour with water just submerging the Chinese medicines. A dose of Chinese herbs is
generally decocted two times, and 250-300 milliliters of strained herbal tea is taken each
time.
The decocting time varies with herbal properties. For example, diaporetics and aromatics
should be decocted with a strong fire for a short time, boiling for 35 minutes; and tonics
should be simmered, boiling for 30-60 minutes.
Because of their different properties, some herbs should be decocted with specific
methods:
To be decocted ahead:
Some minerals and shells with their active ingredients difficult to dissolve in water,
such as talc, dragon's bone, oyster shell and pearl shell, should be kept boiling for
20-30 minutes before other herbs are added.
To be decocted later:
Some aromatics with their active ingredients easy to volatilize, such as peppermint,
amomum fruit and sweet wormwood, should be added after other herbs have been kept boiling
for 5-10 minutes, in order to prevent their active ingredients from escaping.
To be wrapped for decoction:
Some herbs in fine powder or with fine hair, such as talc, plantain seed and inula flower,
should be wrapped in a piece of cloth before decocted with other herbs in order to prevent
stimulation of the throat by turbid herbal tea to cause cough.
To be decocted alone:
Some expensive herbs, such as ginseng, American ginseng and rhinoceros horn, should be
decocted alone. Their herbal tea should be taken alone or after mixed with other herbal
tea.
To be taken following infusion with warm boiled water:
Some herbs with their active ingredients difficult to dissolve in water or easy to be
destroyed after decocted, such as omphalia, hairy vein agrimony and cinnabar, should be
made into fine powder for oral taken following infusion with warm boiled-water or with hot
decoction. Some expensive herbs are often ground into powder for oral taken following
infusion with warm boiled-water in order to save medicinal materials.
To be melted:
Gluey herbs, such as donkey-hide gelation, tortoise-plastron glue and malt extract, should
be dissolved in boiling water or in a decoction before oral administration in order to
prevent them from sticking on the pot and turning charred when decocted with other herbs.
4.2. Methods of Taking:
For decoction, generally one dose is decocted and take two times each day. Patients with
acute and heavy illness can take two doses a day, and those with chronic diseases can take
a dose in two days or every other day. Time for taking herbs:
In general, tonics should be taken before meals; Irritant to the stomach and intestine
should be taken after meals; anthelmintics and cathartics should be taken when stomach is
empty. Antimalarial herbs should be taken two hours before the patient has a fit of
malaria; sedatives should be taken before going to bed; patients with acute diseases take
at any time; and patients with chronic diseases take herbs on time or drink decoction
instead of tea.
Besides decoction of Chinese herbs, there are pill, powder, soft extract, granule or
powder to be taken after infused in warm boiled water, and syrup. In recent years, tablet
and injection of Chinese herbs have been developed. Their characteristics and
administrations are shown in detail in Pharmacology of Traditional Chinese Medical
Formulae.
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