When a patient visits a TCM clinic, he or she has to take and cook the medicine. However, the correct cooking of medicine has a great influence on the efficacy of treatment. Famous doctors in China have attached great importance to the method of decoction of Chinese medicine for many generations. During the decoction process of Chinese medicine, two kinds of changes occur: one is the dissolution of the active ingredients of the medicine; the other is the chemical reaction of various physiologically active ingredients in the medicine. Therefore, the decoction method of tonics has many special considerations. It can be seen that the decoction method of Chinese medicine is very important for effective utilization of drugs and improvement of therapeutic effect. Proper decoction of Chinese herbal medicines can bring out the full effect of the drugs and is important for the prevention and treatment of diseases. The decoction of Chinese herbal medicines is multifaceted, mainly including: 1. Cleaning: Most of the herbal medicines are raw and are generally processed and prepared before sale, so there is no need to wash them before decoction. If you feel that the herbs are dirty, you can rinse them with water quickly before soaking, but do not soak and rinse them to prevent the loss of a large amount of active ingredients that are easily soluble in water, thus affecting the efficacy of the herbs. 2. Apparatus: Decoction apparatus is better than casserole, because the material of casserole is stable and does not react chemically with the ingredients of the drug, and the heat conduction is even, the heat is gentle, the insulation around the pot is strong, and the evaporation of water is small, which is one of the reasons why it has been used since ancient times, but the casserole is more porous and easy to “string taste” and easy to break. In addition, you can also choose enamel pots, stainless steel pots and glass decoction, with acid and alkali resistance, can avoid the reaction with the ingredients of Chinese medicine, a large number of preparations are used. Copper, iron decoction although fast heat transfer but chemically unstable, easy to oxidation, in the decoction of medicine with a variety of ingredients in Chinese medicine chemical reaction and affect the quality, can not use with copper, iron, aluminum pot, tin and other appliances, aluminum pot although fast heat transfer, chemically stable, but aluminum pot is not strong acid strong alkali, not very strong acid and alkali medicine can be used, but is not the ideal decoction appliances. 3, soak Chinese medicine before decoction soak is conducive to the full dissolution of the active ingredients, but also to shorten the decoction time, to avoid the decoction time is too long, resulting in part of the active ingredients depletion, destruction of too much. Most of the drugs should be soaked in cold water, pour the drug into the pot and spread it out, then add room temperature water – room temperature water to soak for 60 minutes, lightly press the herbs when the water is about 2 cm above the plane of the drug. The principle of soaking the herbs through. In summer, the temperature is high, soaking time should not be too long to avoid corruption and deterioration, and in winter it can be longer. Special attention should be paid to the fact that herbs should never be soaked in boiling water. 4. Water The water used for decoction must be odorless, clean and clarified, and contain few minerals and impurities. Generally speaking, any water that people can use for drinking can be used for decocting Chinese medicine. Generally, clear spring water, river water and tap water can be used, while well water must be of good quality. It is best to use purified and softened drinking water to reduce impurities and prevent the precipitation reaction between calcium and magnesium plasma in water and herbal ingredients. How much water to add: According to the theoretical calculation, the amount of water to be added should be the sum of the amount of water absorbed by the tablets, the amount evaporated during the decoction process and the amount of liquid required after the decoction. Although it is difficult to be very precise in adding water in practice, at least the amount of water should be determined according to the dense texture of the tablets, water absorption and the length of decoction time. The amount of water should be 5-8 times the amount of herbs for the first decoction, or the liquid surface should be submerged through the tablets after the tablets are properly pressurized. The amount of water used in the second decoction can be less. After the first decoction is finished, strain out the juice, add water again until it is about 0.5-1 cm above the level of the medicine, and continue to decoct on a martial fire until it boils and then change to a civil fire for 15-20 minutes. For drugs that are hard, sticky or require long decoction, add slightly more water than normal drugs; for drugs that are lax in texture or have a short decoction time because the active ingredients evaporate easily, the liquid surface can be submerged in the drug. Generally, if there are more herbs, flowers and leaves in the formula, which absorb more water, the water should be added before decoction, and more water can be put in. 5. Method (1) Decoction of Chinese medicine should pay attention to the fire and decoction time. Fire refers to the size of the fire and the speed of the fire (large fire and rapid fire are called wu huo, while small fire and slow fire are wen huo). Generally, before boiling, use wu huo, after boiling, use wen huo – small fire to maintain a slight boiling state, so as not to overflow the juice or boil dry too quickly, slow down the evaporation of water, which is conducive to the dissolution of the active ingredients. As for the control of fire and time, it mainly depends on the nature and texture of different drugs. During the decoction process, open the lid of the pot as little as possible to avoid the evaporation of medicinal flavor. (2) Decoction frequency and method. Decoction of Chinese medicine is usually done twice. If the number of decoction is too small, the extraction will be incomplete and the loss of herbs will be large; if the number of decoction is too many, it will not only consume labor and fuel, but also increase the impurities in the decoction. Generally speaking, the active ingredients contained in a pair of Chinese herbs are greatly reduced after two decoctions, so it is better to decoct twice. Generally, the decoction time is calculated after the water is boiled, which is 20-30 minutes for the first decoction and 10-20 minutes for the second decoction. For the treatment of cold and flu, it is advisable to use martial fire and short time, boiling time is l0-20 minutes, and take it while it is hot. Minerals, bones and horns, shells and crustaceans and tonic medicines, which are not easily decocted, should be decocted for a long time with a gentle fire to fully dissolve the active ingredients. The above decoction process requires frequent stirring. The decoction should be filtered out while it is still hot so that the active ingredients do not precipitate on the residue; if the drug is accidentally boiled dry and scorched, the drug cannot be taken because it produces many toxic substances that are harmful to the body. (3) Decoction and extraction of juice. The liquid obtained after decoction of Chinese medicine is generally 150 ml for adults, 100 ml for school-age children and 50 ml for infants. It should be taken twice a day, 300 ml per dose for adults, 200 ml for school-age children and 100 ml for infants. 6. Serving method When taking Chinese medicine, many people are used to decocting a dose of Chinese medicine twice and taking the first and second juices separately. In fact, this method of serving is not scientific. Because the active ingredients such as glycosides, polysaccharides and volatile oils that are easily soluble in Chinese medicine are more in the first decoction, while other insoluble active ingredients are less; while in the second decoction, the content of the soluble active ingredients may be very low, while the insoluble active ingredients are more, so the active ingredients of the two decoctions are not consistent, and the efficacy of the medicine is also very different. Therefore, Chinese herbal medicines should be combined with two decoctions, stirred and divided into two portions, and taken in the morning and evening in order to achieve the best effect. Generally speaking, tonic medicines and laxative medicines should be taken on an empty stomach before meals; medicines for external diseases and head and facial diseases should be taken after meals; medicines for calming the mind should be taken before bedtime; medicines for passing down stools should be taken in the early morning and during the day, avoiding taking them before bedtime and at night. Chinese medicines that stimulate the stomach and intestines should also be taken after meals. The time to take them after meals is usually about half an hour after eating. 7. Appropriate avoidance of food During the period of taking Chinese medicine, attention should be paid to avoid eating raw, cold, sticky and spicy food, and there is no need for additional vitamin supplements. Generally, those who suffer from febrile diseases should avoid spicy, spicy, greasy and indigestible foods, tobacco and alcohol; cold diseases should avoid eating raw and cold foods; jaundice, allergic diseases, carbuncles, tumors and certain skin diseases should avoid eating fishy foods such as fish, shrimp and other stimulating foods; edema patients should avoid eating salt; blood tonic medicine should avoid drinking tea, etc. 8. Handling of special Chinese medicines General drugs can be decocted at the same time, but some of them require different decoction time due to their different nature, performance and clinical use. Some of them need special treatment, and even the same drug has different performance and clinical application due to different decoction time. Therefore, the decoction method should also be considered. (1) Decoction: Minerals, shells, crustaceans, bones, fossils are hard, and the active ingredients of these drugs are difficult to be decocted in a short time, so they should be decocted separately first. In addition, there are some more toxic drugs such as Chuanwu, Radix et Rhizoma, Cao Wu, etc., which can be reduced by long time high temperature decoction, which can play a detoxifying role to reduce their toxicity, and the hydrolysis products after long decoction can play a therapeutic role and make their application safer. (2) after the next: flowers, leaves, and some aromatic herbs containing volatile ingredients (such as mint, Elsholtzia, etc.) long cooking will cause the aroma volatilization, loss of medicinal properties, so it is appropriate after the next, some roots and stems of the active ingredients decoction of Chinese herbal ingredients to heat instability, not resistant to decoction, not easy to long decoction should also be after the next. For example, saffron, rhubarb, senna, etc. should be added to the medicine afterwards. After the other drugs are decocted, they are included in the decoction for 5-10 minutes before the ceasefire, and the decoction can be boiled for 5-10 minutes. (3) Wrap decoction: Wrap a certain medicine in gauze and then decoct it together with other medicines. There are four types of drugs that need to be wrapped for decoction, one is the small seeds, such as carthamus, scape seeds, Celosia, etc., which are particularly sticky when decocted, so if they are not wrapped, they will easily stick to the pot and the juice will not be easily filtered out: secondly, some drugs, such as pu huang, haijin sha, zao shin tu, talc, etc., will easily float on the surface of the liquid or settle at the bottom of the pot when decocted, so they need to be wrapped for decoction; thirdly, some drugs with fluff, such as xin yi, If the decoction is not wrapped, it is not easy to filter out after decoction, and the lint will irritate the throat and cause side effects such as coughing and vomiting after serving. Fourth, drugs containing more starch and mucilage, such as yam, are easy to stick to the pot during the decoction process and need to be decocted; when decocting the above drugs, first wrap the drugs in gauze and then put them into the pot with other drugs, called package decoction. When decocting, the bag should be as loose as possible to avoid the lack of space when the drug is swollen, so that it cannot absorb more water and cannot be decocted thoroughly. (4) Separate decoction: Some valuable drugs (such as ginseng, panax ginseng, antelope horn, wormwood, antler, etc.) can be decocted separately to obtain juice and then added to the decoction to be taken together. In order to avoid the loss of active ingredients in the decoction process with other drugs, resulting in waste. (5) melting: also known as melting, refers to some colloidal Chinese medicine (such as gum, antler gum, turtle gum, etc.) or viscous soluble drugs (such as syrup), decoction is easy to bond with other drugs into a lump, or cause the solution colloid osmotic pressure increases, which is not conducive to the dissolution of the active ingredients of the drug, affecting the decoction effect of the entire drug, or adhering to the bottom of the pot, easy to boil scorched and waste of herbs, should not be decocted with other general drugs. It should be put into another container and stewed in water, or boiled in a small amount of water – note that it should be stirred diligently, then mixed with other drugs and taken together, or taken directly after dissolving with the decoction. (6) Soak: some dosage, and the active ingredients in the drug is easy to dissolve the Chinese medicine (such as senna, fat sea, etc.), do not need to decoction, directly with boiling water can be taken after soaking. (7) Punch: Some drugs that are difficult to dissolve in water, some powder-like drugs (such as amber powder, vermilion) should not be decocted, or some more valuable Chinese medicines (such as Panax ginseng powder, ginseng powder) or drugs that should not be decocted (such as mannitol), liquid drugs (such as bamboo leach, ginger juice, etc.), can be taken directly into the decoction and mixed, or directly with warm water to avoid drug loss. Some drugs are more valuable and the dosage is small, if decocted with other drugs, the juice will be adsorbed by other drugs, thus affecting the efficacy of the drug. For example, ox huang, musk, pearl powder, amber, cordyceps, panax quinquefolium powder and so on. In addition, there are some drugs such as mother-of-pearl powder, although not a valuable drug, but research into fine powder, than adding other drugs decoction after taking the effect is better.