Questions about Chinese Herbs
Q : What are Chinese Medicines made out of?
| A: Any type of material can be a Chinese medicine. However, plants (herbs) make up the bulk of prescriptions, followed by animal products and then minerals. Plants cover whole grasses, roots, stems, leaves, flowers, barks and fruits. Animal products consist of insects, fishes, shells, worms and animals, while minerals include gypsum, realgar and sulphur.
Q : How do you take Chinese medicine?
A: Traditionally, Chinese medicines are placed in water and boiled. When the residue is removed, the end product is called a decoction. Other forms of Chinese medicines include boluses, powders, pastes, pills as well as capsules, tablets, granules, syrups, fluids for injection, etc.; these are used to suit the individual needs of each patient.
Q : What are the "four natures" and the "five flavors?"
A: The four natures in Chinese medicine are "cold, cool, warm and hot". The five flavors are "sour, bitter, sweet, spicy hot and salty". TCM believes that since Chinese medicines have such different properties they have different effects and can work on specific organs or meridians. For example, hot and spicy medicines like ginger and onion make one sweat; sweet-tasting herbs like red dates and pilose asiabell root have tonifying effects. Clinically, people with a dry throat and bitter taste in their mouth are regarded as having excessive heat inside their bodies; they need to take medicines that are relatively cold and cool. People who tend to suffer from internal coldness need to ingest medicines that are relatively warm and tonifying.
Q : What are the lifting, descending, floating and sinking effects of TCM medicines?
A: These different "spatial" effects reflect the effects of tendencies of Chinese medicines. A "lifting" effect enables the medicinal properties to move from the lower region towards the upper region; a "descending" effect enables the medicinal properties to descend to the lower parts of the body; a "floating" effect drives the medicinal properties to reach the different parts of the body or to move from upper to the lower region; while a "sinking" effect means consolidating and restricting, enabling the facilitation of urination and defecation. Since different diseases have various developmental tendencies (moving upwards, downwards, spreading outwards and moving inwards), medicines that can match the conditions of these diseases or improve on or eliminate their symptoms are used. For example, for Influenza (common cold), TCM believes that the position of the disease lies on the upper part and on the exterior, and then it is appropriate to use medicines that have the nature of rising and dispersing, such as ephedra and cassia twig, medicines that have descending and sinking natures should not be used.
Q : What is meant by medicine being prescribed by meridian?
A: Applying medicine according to the meridians is to demonstrate the position where the medicine will have the most effect on. Medicines are grouped according to their natures. Meridians mean the different internal organs that are linked by energy channels.
There are some medicines that apply to only one meridian, but others can be applied to several meridians. The matching of medicines with meridians helps raise the efficacy of the medicine. However, since the meridians and the internal organs are interrelated and influence one another biologically, in applying medicines it is necessary to consider the relationship between the meridians and the internal organs. Therefore, most TCM practitioners usually apply medicines that match more than one meridian.
Q : How do different herbal combinations work together in TCM?
A: Herbal medicines can complement and assist each other in certain combinations:
|| Mutual reinforcement leads to a synergy effect when two drugs of a similar nature are used simultaneously. For example, when Rhizoma Anemarrhenae and gypsum are used together, the effect of heat clearing is enhanced.
|| Mutual assistance means the major ingredient of a prescription is enhanced by other subsidiary drugs, for example when Rhizoma Coptidis is used to treat dysentery, Radix Aucklandiae can assist to smooth bowel movements and arrest abdominal pain.
|| Mutual suppression helps to reduce the toxicity of a drug. For example, the toxicity of Fructus Crotonis can be reduced by mung beans.
|| Mutual restraint occurs when two drugs, when combined together inhibit the toxicity of each other, for example, ginseng and Faeces Trogopterorum.
|| Mutual aversion means when two drugs are used together, the healing effect of one drug is inhibited by another, such as the invigoration effect of ginseng can be inhibited by radish seeds.
|| Mutual incompatibility means that certain drugs in combination can lead to adverse effects; for example, liquorice root will increase the toxicity of Flos Genkwa .
|| Single application refers to a drug used alone in order to exert its own specific action, e.g. using ginseng to replenish primordial qi.
These contraindications are not absolute and are for reference only. However, in actual practice, TCM practitioners base their prescriptions on these principles.
Q : What is the medicinal guiding effect in herbal prescriptions?
A: In TCM, the medicinal guiding effect means augmenting the overall efficacy of the medicine, enabling it to work on specific meridians, reducing toxicity and improving flavor.
|| Harmonize and reinforce the drug's actions: Example: in wind-heat type influenza when individuals present with a high fever and thirst, bamboo leaf and reed rhizome are used. These two herbs together can strengthen the effect of clearing heat and bringing down the fever.
||Guiding drugs to work on specific meridians: Example: if the pain is located in the lower limbs and feet, then achyranthes root is said to act as a guide to let other drugs travel to the painful location.
|| Reducing the toxicity of drugs: Mylabris is usually used to treat liver cancer, however since this insect also has severely toxic, mung beans would also be used as the guiding medicine to prevent harmful effects from occurring.
|| Improving flavor: Example: the fishy smell of some animal products can be eliminated by the addition of millet wine. Ingredients like honey, malt sugar and sugar cane juice are generally used to make medicines more palatable.
Q : Why is Chinese medicine prepared in various ways?
A: Chinese medicines are prepared in such a way to:
- Lower / eliminate toxicity and side effects;
- Alter or ameliorate the nature of the medicine, and to elevate its healing effects:
- Alter or reinforce the parts and tendencies of the medicine for their special effect;
- To facilitate their mixing with other medicines so that they can be made into different forms;
- To maintain the purity of the medicinal materials;
- Facilitate storage and aid consumption.
Q : How can you determine the quality of Chinese medicinal materials?
A: Due to differences in growing environment and the nature of the soil, there are big differences in the effective ingredients of plants used as TCM. There are also differences in quality. Generally speaking, medicinal materials which are grown in the wild and from well known area are considered to be of better quality than those which are cultivated by man. Furthermore, the size, shape, color, texture and flavor of medicinal materials are factors determining the quality of a Chinese medicine. To ensure that you buy high quality herbs, please purchase Chinese medicine from creditable herbal pharmacies.
Q : How do you store Chinese medicines?
A: If Chinese medicines are not stored properly, their effectiveness could become compromised. This is indicated by certain physical changes, like changes in colour. Worm infestation and mould can also occur if the medicine has been stored in a place with a relatively high room temperature and humidity (>70%) or when the medicines have a relatively higher water content. In such a situation, medicinal materials could also lose their essential oils and become "covered with oil". In order to keep your Chinese medicine from deteriorating, place it in a dry, well-ventilated and dark place. Ideally, storage in a cool place will lessen the likelihood of mould or pest infestation occurring.
Chinese Pharmaceutics Identification
Published by Shanghai Science and Technology Publishing House, 6th edition.
CM Promotion Group - School of Chinese Medicine, CUHK.
Translated and Edited by:
Jennifer Eagleton, BA, MA (Asian Studies), Integrated Chinese Medicine Holdings Ltd.
Lawrence Lau, Ph.D., Integrated Chinese Medicine Holdings Ltd.
Rose Tse, Integrated Chinese Medicine Holdings Ltd.