Chinese herbology

thumb|right|Dried herbs and plant portions for Chinese herbology at a [[Xi'an market]]

Chinese herbology or Chinese materia medica () is the theory of traditional Chinese pharmacotherapy, which accounts for the majority of treatments in traditional Chinese medicine (TCM). It is analogous to other traditional materia medica systems.

The term herbology is misleading in the sense that, while plant elements are by far the most commonly used substances, animal, human, and mineral products are also used, some of which are poisonous. In the they are referred to as () which means "poison-medicine". Paul U. Unschuld points out that this is similar etymology to the Greek and so he uses the term pharmaceutic. Thus, the term medicinal (instead of herb) is usually preferred as a translation for ().

A Nature editorial described TCM as "fraught with pseudoscience", and said that the most obvious reason why it has not delivered many cures is that the majority of its treatments have no logical mechanism of action. Research into the effectiveness of traditional Chinese medicinal therapy is of poor quality and often tainted by bias, There are concerns over a number of potentially toxic Chinese medicinals,

History

thumb|right|upright=0.6|Chinese pharmacopoeia

The practice of Chinese materia medica stretches back for millennia. The earliest written record of prescriptions is the manuscript Recipes for 52 Ailments (, Wǔshí'èr Bìngfāng), discovered in the Mawangdui tombs, which were sealed in 168 BCE.

Later tradition credits the legendary figure Shénnóng (, lit. "Divine Farmer") as the founder of Chinese materia medica. He is said to have lived around 2800 BCE and to have tasted hundreds of substances to ascertain their medicinal value. The first and most important herbal classic attributed to him is the (, Shennong's Materia Medica). While the original text has been lost, it was transcribed and preserved in later commentaries. Modern scholarly research suggests that the text was compiled in the late Western Han period, likely around the first century BCE, and was not written by a single author. The Běn Cǎo Jīng classifies 365 substances, including plants, animals, and minerals into three categories:

"Superior" (, shàng pǐn): substances considered safe for long-term consumption to maintain health, with few to no side effects.
"Medium" (, zhōng pǐn): substances with some therapeutic action that may have mild toxicity depending on the dosage.
"Inferior" (, xià pǐn): substances taken for specific illnesses, often for shorter periods, as they are considered to have a higher potential for toxicity. After passing through numerous changes, the original work now circulates as two separate books: the Treatise on Cold Damage Disorders and the Essential Prescriptions of the Golden Casket, which were edited separately in the eleventh century during the Song dynasty.

Succeeding generations augmented these works, as in the (), a 7th-century Tang dynasty Chinese treatise on medicinal substances.

There was a shift in emphasis in treatment over several centuries. A section of the Huangdi Neijing Suwen including Chapter 74 was added by Wang Bing in his 765 edition. In which it says: "The ruler of the disease is called the Sovereign, the aid to the Sovereign is called the Minister, the one that complies with the Minister is called the Envoy (Assistant), this is not a distinction between the three ranks of superior and inferior." The last part is interpreted as stating that these three rulers are not the three classes of Shénnóng mentioned previously. This chapter in particular outlines a more forceful approach. Later on Zhang Zihe ( Zhang Cong-zhen, 1156–1228) is credited with founding the 'Attacking School' which criticized the overuse of tonics.

Arguably the most important of these later works is the Compendium of Materia Medica (, ) compiled during the Ming dynasty by Li Shizhen, which is still used today for consultation and reference.

The use of Chinese herbs was popular during the medieval age in western Asian and Islamic countries. They were traded through the Silk Road from the East to the West. Cinnamon, ginger, rhubarb, nutmeg and cubeb are mentioned as Chinese herbs by medieval Islamic medical scholars Such as Rhazes (854–925 CE), Haly Abbas (930–994 CE) and Avicenna (980–1037 CE). There were also multiple similarities between the clinical uses of these herbs in Chinese and Islamic medicine.

Raw materials

There are roughly 13,000 medicinals used in China and over 100,000 medicinal recipes recorded in the ancient literature. Plant elements and extracts are by far the most common elements used. In the classic Handbook of Traditional Drugs from 1941, 517 drugs were listed – out of these, only 45 were animal parts, and 30 were minerals.

Some animal parts used as medicinals can be considered rather strange such as cows' gallstones.

Furthermore, the classic materia medica describes the use of 35 traditional Chinese medicines derived from the human body, including bones, fingernail, hairs, dandruff, earwax, impurities on the teeth, feces, urine, sweat, and organs, but most are no longer in use.

Preparation

Decoction

[[File:Chinese herbal decoction (一貫煎) on snow.jpg| thumb | 220x124px | right | alt= An image of decocted Chinese medicine 一貫煎 on snow, taken in the United States. The snow is on the border of a forest near a residential area, with a small lake in the background near trees. |

A traditional Chinese herbal decoction (湯劑/汤剂)]]

Typically, one batch of medicinals is prepared as a decoction of about 9 to 18 substances. Some of these are considered as main materials, some as ancillary; within the ancillary , up to three categories can be distinguished. Some ingredients are added to cancel out toxicity or side-effects of the main ingredients; on top of that, some medicinals require the use of other substances as catalysts.

Chinese patent medicine

Chinese patent medicine () is a kind of traditional Chinese medicine. They are standardized herbal formulas. From ancient times, pills were formed by combining several medicinals and other ingredients (excipients), which were dried and ground into a powder. They were then mixed with a binder and formed into pills by hand. The binder was traditionally honey. Modern teapills, however, are extracted in stainless steel extractors to create either a water decoction or water-alcohol decoction, depending on the medicinal substance used. They are extracted at a low temperature (below ) to preserve essential ingredients. The extracted liquid is then further condensed, and some raw medicinal powder from one of the medicinal ingredients is mixed in to form a medicinal dough. This dough is then machine cut into tiny pieces, a small amount of excipients are added for a smooth and consistent exterior, and they are spun into pills.

These medicines are not patented in the traditional sense of the word. No one has exclusive rights to the formula. Instead, "patent" refers to the standardization of the formula. In China, all Chinese patent medicines of the same name will have the same proportions of ingredients, and manufactured in accordance with the PRC Pharmacopoeia, which is mandated by law. However, in western countries there may be variations in the proportions of ingredients in patent medicines of the same name, and even different ingredients altogether.

Several producers of Chinese herbal medicines are pursuing FDA clinical trials to market their products as drugs in U.S. and European markets.

Chinese herbal extracts

Chinese herbal extracts are herbal decoctions that have been condensed into a granular or powdered form. Herbal extracts, similar to patent medicines, are easier and more convenient for patients to take. The industry extraction standard is 5:1, meaning for every five pounds of raw materials, one pound of herbal extract is derived.

Categorization

There are several different methods to classify traditional Chinese medicinals:

The Four Natures ()
The Five Flavors ()
The meridians ()
The specific function.

Four Natures

The Four Natures are: hot (), warm (), cool (), cold () or neutral (). Hot and warm medicinals are used to treat cold diseases, while cool and cold medicinals are used to treat hot diseases. A flavor implies certain properties and presumed therapeutic "actions" of a substance: saltiness "drains downward and softens hard masses"; or exterior-resolving

heat-clearing
transforming phlegm, stopping coughing and calming wheezing

Color

Color is not only a valuable means of identifying herbs, but in many cases also provides information about the therapeutic attributes of the material. For example, yellow herbs are referred to as (yellow) or (gold). (Cortex Phellodendri) means 'yellow fir", and (Flos Lonicerae) has the label 'golden silver flower." Since TCM has become more popular in the Western world, there are increasing concerns about the potential toxicity of many traditional Chinese medicinals including plants, animal parts and minerals. The toxicity in some cases could be confirmed by modern research (i.e., in scorpion); in some cases it could not (i.e., in Curculigo). Further, ingredients may have different names in different locales or in historical texts, and different preparations may have similar names for the same reason, which can create inconsistencies and confusion in the creation of medicinals, with the possible danger of poisoning. Edzard Ernst "concluded that adverse effects of herbal medicines are an important albeit neglected subject in dermatology, which deserves further systematic investigation." Research suggests that the toxic heavy metals and undeclared drugs found in Chinese medicines might be a serious health issue.

Substances known to be potentially dangerous include aconite, powdered centipede, the Chinese beetle (Mylabris phalerata, Ban mao), and certain fungi. There are health problems associated with Aristolochia.

Also, adulteration of some Chinese medicine preparations with conventional drugs which may cause serious adverse effects, such as corticosteroids, phenylbutazone, phenytoin, and glibenclamide, has been reported.

However, many adverse reactions are due to misuse or abuse of Chinese medicine.

Most Chinese medicinals are safe but some have shown not to be. Reports have shown products being contaminated with drugs, toxins, or false reporting of ingredients. Some medicinals used in TCM may also react with drugs, have side effects, or be dangerous to people with certain medical conditions.

Efficacy

Only a few trials exist that are considered to have adequate methodology by scientific standards. Proof of effectiveness is poorly documented or absent. A 2016 Cochrane review found "insufficient evidence that Chinese Herbal Medicines were any more or less effective than placebo or hormonal therapy" for the relief of menopause related symptoms. A 2012 Cochrane review found no difference in decreased mortality for SARS patients when Chinese herbs were used alongside Western medicine versus Western medicine exclusively. A 2010 Cochrane review found there is not enough robust evidence to support the effectiveness of traditional Chinese medicine herbs to stop the bleeding from haemorrhoids. A 2008 Cochrane review found promising evidence for the use of Chinese herbal medicine in relieving painful menstruation, compared to conventional medicine such as NSAIDs and the oral contraceptive pill, but the findings are of low methodological quality. A 2012 Cochrane review found weak evidence suggesting that some Chinese medicinal herbs have a similar effect at preventing and treating influenza as antiviral medication. Due to the poor quality of these medical studies, there is insufficient evidence to support or dismiss the use of Chinese medicinal herbs for the treatment of influenza.

Ecological impacts

thumb|upright|Dried [[seahorses like these are extensively used in traditional medicine in China and elsewhere.]]

The traditional practice of using now-endangered species is controversial within TCM. Modern Materia Medicas such as Bensky, Clavey and Stoger's comprehensive Chinese herbal text discuss substances derived from endangered species in an appendix, emphasizing alternatives.

Parts of endangered species used as TCM drugs include tiger bones and rhinoceros horn. Poachers supply the black market with such substances, and the black market in rhinoceros horn, for example, has reduced the world's rhino population by more than 90 percent over the past 40 years. Concerns have also arisen over the use of turtle plastron and seahorses.

TCM recognizes bear bile as a medicinal. In 1988, the Chinese Ministry of Health started controlling bile production, which previously used bears killed before winter. Now bears are fitted with a sort of permanent catheter, which is more profitable than killing the bears. More than 12,000 asiatic black bears are held in "bear farms", where they suffer cruel conditions while being held in tiny cages. The catheter leads through a permanent hole in the abdomen directly to the gall bladder, which can cause severe pain.

Increased international attention has mostly stopped the use of bile outside of China; gallbladders from butchered cattle () are recommended as a substitute for this ingredient.

Collecting American ginseng to assist the Asian traditional medicine trade has made ginseng the most harvested wild plant in North America for the last two centuries, which eventually led to a listing on CITES Appendix II.

Chinese medicinal plant materials (CMPMs) release chemicals that attracts the Drugstore beetle, leading to the accumulation of this pest and further infestation and damage to these plants.

Herbs in use

Chinese herbology is a pseudoscientific practice with safety hazards and misleading health advice. Product quality is also potentially unreliable, though regulatory bodies and standards such as China GMP (Good Manufacturing Process) have been set up to maintain quality in their respective jurisdictions.

There are over 300 herbs in common use. Some of the most commonly used herbs are Ginseng (), wolfberry ( (Angelica sinensis, ), astragalus (), atractylodes (), bupleurum (), cinnamon (cinnamon twigs () and cinnamon bark ()), coptis (), ginger (), hoelen (), licorice (), ephedra sinica (), peony (white: and reddish: ), rehmannia (), rhubarb (), and salvia ().

To reitertate, there is a lack of high-quality scientific research on herbology practices and product effectiveness for anti-disease activity. although these herbs are not universally recognized as such in other texts. The herbs are:

{| class="wikitable"

!Binomial nomenclature

!Chinese name

!English common name (when available)

| Agastache rugosa (藿香) or Pogostemon cablin (廣藿香, 广藿香) || (), (, )||Korean mint, Patchouli

| Alangium chinense || (, )||(translated) Mountain henbane

| Ardisia japonica || ()||Marlberry

| Aster tataricus ( Galatella tatarica) || ()||Tatar aster, Tartar aster

| Astragalus mongholicus ( A. membranaceus, A. propinquus) || (, ) or () || , (Tw.): ()|| Sichuan lovage, Szechuan lovage (Szechwuan lovage), belongs to the genus hemlock-parsley

| Coptis chinensis || (, )||Chinese goldthread

| Corydalis yanhusuo || ()||Chinese poppy, Yan Hu Suo, close relative to Corydalis ambigua and fumewort

| Croton tiglium || ()||Purging croton

| Daphne genkwa || ()||Lilac daphne

| Datura metel || ()||Devil's trumpet

| Datura stramonium || (, )||Jimson weed

| Dendrobium nobile || () or (, )||Noble dendrobium

| Dolomiaea costus ( Saussurea costus) || (, )||Costus root

| Ephedra sinica || (, )||Chinese ephedra

| Eucommia ulmoides || ()||Hardy rubber tree

| Euphorbia pekinensis || ()||Peking spurge

| Flueggea suffruticosa ( Securinega suffruticosa) || (, )

|a type of shrub-like bushweed of the family Phyllanthaceae

| Forsythia suspensa || (, , )||Weeping forsythia

| Gentiana loureiroi || ()

||Loureiro's gentian

| Gleditsia sinensis || ()||Chinese honeylocust

| Glycyrrhiza uralensis || ()|| Licorice

| Hydnocarpus castaneus ( Hydnocarpus anthelminthicus) || (, )||Chaulmoogra tree

| Hydrangea febrifuga ( Dichroa febrifuga) || ()||Blue evergreen hydrangea, Chinese quinine

| Ilex chinensis ( Ilex purpurea) || ()||Purple holly

| Leonurus japonicus || ()||Chinese motherwort

| Lobelia chinensis || (, )||Creeping lobelia

| Phellodendron amurense || (, )||Amur cork tree

| Platycladus orientalis (formerly Thuja orientalis) || (, )|| Chinese arborvitae

| Pseudolarix amabilis || (, )|| Golden larch

| Psilopeganum sinense || (, )||Naked rue

| Pueraria montana var. lobata || ()||Kudzu

| Pulsatilla chinensis ( Anemone pulsatilla var. chinensis) || (, )||Chinese foxglove

| Rheum officinale || (, )||Chinese or Eastern rhubarb

| Rhododendron qinghaiense || (, )

|Qinghai rhododendron (Qinghai alprose)

| Schisandra chinensis || () ||Chinese magnolia vine

| Scutellaria baicalensis || (, )|| Baikal skullcap

| Stemona tuberosa || ()

| tuberous stemonia of the family Stemonaceae

| Stephania tetrandra || ()||Stephania root

| Styphnolobium japonicum (formerly Sophora japonica) || (), (, ), or ()|| Pagoda tree

| Trichosanthes kirilowii || ()|| Chinese cucumber

| Wikstroemia indica || ()|| Indian stringbush

Other Chinese herbs

In addition to the above, many other Chinese herbs and other substances are in common use, and these include:

Akebia quinata ()
Arisaema heterophyllum ()
Chenpi (sun-dried tangerine (mandarin) peel) ()
Clematis chinensis ()
Concretio silicea bambusae ()
Cordyceps sinensis ()
Curcuma longa, Curcuma aromatica ()
Dalbergia odorifera ()
Myrrh ()
Frankincense ()
Prunus persica ()
Patchouli ()
Polygonum ()
Sparganium stoloniferum ()
Zedoary (Curcuma zedoaria) ()

Herbal Formulas

Types of Formulas

Traditional Chinese herbs are used either standalone, or in a grouping, jointly with other herbs. When several herbs are used together, this amalgamation is called a 'herbal formula'.

There are, generally speaking, three types of herbal formulas used in TCM:

Classic Formulas – these are formulas which TCM practitioners believe have withstood the test of time over the centuries, and are mentioned in classical texts, such as the Shanghan Lun.
Patent Formulas – these are either classic formulas, or newer commonly used formulas created in recent decades. The patent formulas stand out in that their usage is common enough, that they are frequently mass-produced by large companies, in China, the United States, and elsewhere.
Custom-Made Formulas – these formulas are composed by a TCM Practitioner, to match the specific diagnosis and medical condition of a patient. These formulas are often partially based on the older, classic formulas.

Formula Hierarchy

The prescription of TCM formulas, is based on 4-tier system of hierarchy. The 4-tiers are: Jun (君), Chen (臣), Zuo (佐) and Shi (使). These four tiers are often translated as: Sovereign, Minister, Assistant, Courier; or Monarch, Minister, Assistant, Envoy (also: 'Guide').

thumb|An illustrative summary of commonly-used Envoy Herbs (Guiding Herbs) in Traditional Chinese Medicine

This feudal-like hierarchy denotes the power and role of each substance in a given formula. The Jun is the substance which is usually of the highest relative dosage, and leads the main action of the formula. In the majority of formulas, there is only one Jun (Monarch) substance. Sometimes, a formula may feature 2-3 Jun substances, or lack a dominant Jun substances altogether. The Chen support the Jun in its actions, and provide additional uses for the medical purpose of the formula. The Zuo assist the Jun and Chen, but are given at a much lower dosage (relative to themselves), to deemphasize their influence, for various reasons. The Shi's main role is to help guide the formula to the correct bodily areas or organ systems inside of which it is meant to act. The Shi are also sometimes used "to harmonize the properties of other substances in the formula".

Most substances can serve as either Jun (Monarch), Chen (Minister) or Zuo (Assistant) – the first three tiers in the medicinal hierarchy. But only certain substances are considered fit to serve as Shi. This is because only some substances are believed to have the ability, to guide other substances into a given bodily area or organ system.

Matching and contrasting herbs

Within TCM formulas, there are also strict rules about which herbs pair well together (Dui Yao), and which are either contradictory, incompatible, or may cause a reaction amongst themselves, or with Western Medicine Drugs. For example: Gan Cao (Licorice) is incompatible with the herbs Yuan hua, Jing Da Ji, Hai Zao and Gan Sui. It may also alter the therapeutic effects of corticosteroids.

Notable people

Ji Desheng (1898–1981), Chinese herbalist from Nantong.
Li Ching-Yuen (died 1933), Chinese herbalist, martial artist and tactical advisor.
Aw Chu Kin (died 1908), Burmese Chinese herbalist, inventor of Tiger Balm.
Ing Hay (1862–1952), migrated to the United States in 1887 and practiced traditional Chinese medicine in Oregon.