The theory of Chinese herbal medicine

Chinese herbal medicine does not primarily see illness as a named condition, but as a disturbed balance. Lifestyle, emotions, diet, hereditary disposition and environment are all part of it. The diagnosis establishes which pattern is present (for example heat, cold, dampness, wind, phlegm, deficiency or excess), and each pattern has herbs and formulas with an opposite action.

Hence the saying: one disease, different treatments; different diseases, the same treatment. Two people with the same Western diagnosis can have a very different pattern and thus receive a different formula, while one formula can suit widely different diseases if the underlying pattern is the same. In practice many therapists combine both: they name the disease the Western way and distinguish the Chinese patterns within it.

Traditional diagnosis rests on four pillars: asking, looking (among other things at the tongue), feeling (among other things the pulse) and listening or smelling. A tongue can be red, pale, swollen or coated; a pulse rapid, slow, superficial, deep, slippery or wiry. That is why each formula lists the tongue and pulse by which the pattern can be recognized.

Qi has no Western counterpart. It is usually translated as energy or life force, but it is at the same time the material basis of everything and the force that sets everything in motion. The Chinese character shows a bowl of rice with steam rising from it: the rice stands for the nourishing, material part, the steam for the warm, moving part that can do work.

Qi warms and animates the body, protects against illness, makes organs and systems work and makes consciousness possible. A classical saying goes: 'no free flow, then pain; free flow, then no pain'. Where qi is blocked, pain arises and a deficiency arises elsewhere, just as a dam builds up water behind it and leaves it dry in front. With age, qi declines.

Many kinds of qi have been described, such as the defensive qi (wei qi) at the surface, the nourishing qi (ying qi) and the qi extracted from food in spleen and stomach, but according to tradition they are all forms of one qi.

Qi flows through meridians: non-material pathways that connect the body with the internal organs. There are twelve regular meridians, six for the hand and six for the foot, each with its own series of acupuncture points. They run more or less vertically; the hand meridians begin or end at the fingertips, the foot meridians at the toes.

The Chinese organs are functional systems, not anatomical organs. The 'kidney' stores the essence, governs the bones and marrow, shows in the hair and hearing and also includes reproduction and hormones. A deficiency of kidney qi closely resembles ageing: lower back pain, brittle bones, weakness, fatigue, dizziness and forgetfulness, with thinning hair and poorer hearing. The 'spleen' transforms food and fluids and is the source of acquired qi; the 'liver' ensures a free flow of qi and blood and is sensitive to stress.

Each herb has a preference for certain meridians; this is called the channel entry. For cough from lung heat, choose herbs that go to the lung meridian and cool lung heat, such as huang qin and mulberry root bark; for liver fire, herbs that go to the liver, such as long dan cao and self-heal. If liver fire affects the lung, combine both.

Each herb has a nature: cold, cool, warm or hot. Herbs without a clear tendency are called neutral, although they too often lean slightly towards warm or cool. The nature is derived from how the body reacts to the herb. What relieves heat, such as gypsum and shan dou gen for fever, thirst and a red, sore throat, is cold or cool. What relieves cold, such as dried ginger, cinnamon bark and aconite for cold abdominal pain and ice-cold limbs, is warm or hot.

Herbs are classified by five tastes: pungent, sweet, sour, bitter and salty, plus astringent and bland. The taste can partly really be tasted, but is mainly derived from the action. Kudzu root tastes sweet, which fits with generating body fluids; because it also works outwards and brings out rashes, it is also given the taste pungent.

Herbs have a direction. Light parts such as flowers, leaves, bark and twigs usually rise and float; heavy parts such as seeds, fruits, minerals and shells descend and sink. Perilla leaf, chrysanthemum and mulberry leaf go up and outwards; perilla seed, immature bitter orange, magnetite and hematite go down and inwards. Yet in the end the action decides: platycodon lifts the lung qi and works on the throat, while bai qian makes the qi descend in cough with much phlegm.

Rising and floating herbs suit complaints in the upper body and at the surface, such as colds, or sinking complaints such as prolapse. Descending and sinking herbs suit complaints in the lower body and inside, and complaints that want to go upwards, such as vomiting, hiccups, cough, restlessness and rising liver yang.

Many Chinese herbs are processed before use. This is called pao zhi. It includes washing and cutting, but above all roasting with honey, wine or vinegar, steaming and processing with ginger juice. The processing changes the action.

Chinese doctors preferred 'genuine regional herbs' (dao di yao cai): herbs from the region where they have traditionally grown best. Examples are dang gui from Gansu, goji from Ningxia, rhubarb from Qinghai, huang qi from Inner Mongolia, ginseng, xi xin and schisandra from the north-east, huang lian, chuanxiong and bei mu from Sichuan, rehmannia, niu xi and Chinese yam from Henan, tangerine peel and sha ren from Guangdong, and notoginseng and fu ling from Yunnan.

Good quality can be recognized by large, whole pieces rather than finely cut or ground herb (ground herb oxidizes quickly and is easy to adulterate, for example goldenseal with turmeric), a bright colour, the right moisture (not brittle, not clammy), a characteristic smell and above all the taste. Old herb tastes different.

Cultivated herbs can be harvested at the right moment; with wild-collected herbs that is not always the case. Many wild plants, such as goldenseal and American ginseng, are under pressure from overharvesting. Where possible, choose organically grown or forest-grown herbs.

Shen Nong's classical materia medica describes seven ways in which herbs relate to one another. They form the basis for composing a formula.

Chinese herbal medicine works mainly with formulas: fixed combinations of three to more than twenty herbs that have been refined over centuries. They treat a complex pattern rather than a single complaint, and the herbs work more strongly together than separately. A therapist starts with a classical base formula and adapts it to the person.

The roles in a formula are borrowed from the Confucian court. The emperor carries the main action, the minister strengthens it, the assistant reduces unwanted effects and the servant harmonizes the whole. In ma huang tang, ma huang induces sweating (emperor), cinnamon twig strengthens this (minister), apricot kernel softens the drying action (assistant) and licorice brings everything into balance (servant).

Tierra's book lists as base formulas, among others: gui zhi tang and ma huang tang (exterior), bai hu tang (heat), xiao chai hu tang (harmonizing), si jun zi tang (qi), si wu tang (blood), liu wei di huang wan (yin), ba wei di huang wan (yang), da cheng qi tang (purging), wu ling san (dampness), bao he wan (digestion), xiao yao san (regulating qi), suan zao ren tang (calming), er chen tang (phlegm) and du huo ji sheng tang (rheumatism).

Many classical formulas come from the Shang Han Lun ('Treatise on Cold Damage') by Zhang Zhongjing from the second century. Via Japan this gave rise to kampo. Kampo doctors work more with abdominal diagnosis and use about half to a third of the Chinese dosage.

The Chinese materia medica is the result of thousands of years of uninterrupted clinical experience and distinguishes much more finely than most Western herbals. Where a Western book lists ten herbs 'for cough', a Chinese book classifies them by the kind of cough. Yet many Western herbs can be described with the same concepts, and many 'Chinese' herbs come from elsewhere: frankincense, myrrh and dragon's blood from the Middle East, clove, pepper and cinnamon from South-East Asia, and American ginseng, corn silk and echinacea from America.

In Chinese practice herbs are mainly used as decoctions; aromatic herbs such as mint, huo xiang and gou teng go in only for the last few minutes. Western herbalists use many tinctures. According to Chinese medicine, alcohol warms, disperses and moves the blood; this suits cold, dampness and wind, but less so yin deficiency.

In the Chinese materia medica the pharmaceutical name first gives in Latin the part used and then the plant. That way you can tell what is used.