1. Decoction method of Chinese herbal medicines 1.1 Whether Chinese herbal medicines need to be washed before decoction Chinese herbal medicines are mostly raw medicines, which are generally processed and prepared before being sold, so there is usually no need to wash them before decoction. If you feel that the herbs are dirty, you can rinse them with water quickly before soaking. 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. 1.2 Vessels for decoction of Chinese herbal medicines The vessels for decoction of Chinese herbal medicines are generally tile jars and casseroles, but enamel and aluminum products are also good, but iron and copper vessels should not be used to prevent these metal objects from reacting with the medicine and affecting its efficacy or even causing harm to human body. 1.3 How to decoct Chinese medicine 1.3.1 Soak the medicine into the pot and spread it out, then add cold water to an inch above the level of the medicine and soak for 0.5-1 hour. If there are more flowers and leaves in the formula and the water absorption is larger, add additional water before decoction so that the water is about 1-2 cm above the level of the medicine. 1.3.2 Heating fire is generally used before the drug is boiled, and it is advisable to change to civil fire after boiling. However, some herbal medicines for treating external diseases can also be decocted for about 5 minutes after boiling without changing the fire to the civil fire. 1.3.3 Decoction time Generally, the first decoction should continue to be cooked for 20-30 minutes after boiling. However, the specific time varies with different drugs. For example, for the treatment of exogenous diseases, most of the drugs are aromatic, so the decoction time should be short to avoid the loss of aroma and medicinal properties due to long cooking; most of the drugs for nourishment can be decocted for a longer time to make the active ingredients fully dissolved and the medicinal power complete; most of the mineral drugs such as shells and fossils should be decocted for a longer time. 1.3.4 After the first decoction, strain out the juice and add cold water until it is about 0.5-1 cm above the level of the medicine, then continue to decoct on a wu huo fire until it boils and then change to a wen huo fire for 15-20 minutes. 1.4.1 Decoction of certain toxic drugs (e.g. Radix et Rhizoma Polygonati, Aconite, etc.) can be detoxified by long decoction, while mineral drugs (e.g. keel bone), shellfish (e.g. oyster) and certain roots and tubers need to be decocted first because the active ingredients can be dissolved by longer decoction. The first decoction usually requires 1-2 hours of decoction in advance, and then other drugs are put into the decoction together, and the remaining method is the same as above. 1.4.2 The aromatic drugs (e.g. peppermint, sand, mullein, etc.) should be added 5-10 minutes before the decoction, because the aroma will volatilize and the medicinal properties will be lost if they are boiled for a long time. 1.4.3 Wrap decoction of some powdered drugs (such as cattail) and small plant seeds (such as psyllium), to be wrapped in gauze decoction, so as not to float or cause sticky pot, in order to decoction or drinking. 1.4.4 molten gum drugs (such as gum, antler gum, turtle board gum, etc.) are dissolved when the liquid is warm, and then mixed and taken; or put in a pot with water to steam and dissolve, into the liquid to take warm. 1.4.5 Some powder-like drugs (such as amber powder, vermilion) should not be decocted, but can be mixed directly into the decoction; or more valuable drugs (such as ginseng, panax ginseng) are usually made into bulk, and should be taken with other drugs decocted; liquid drugs in the prescription (such as bamboo leach, ginger juice, etc.) are also not decocted, and are mixed with other drugs. 1.5 How many times should a pair of Chinese medicine be decocted? Generally speaking, the active ingredients in a pair of Chinese medicine are greatly reduced after decocting twice, so it is better to decoct twice. However, for prescriptions with a large amount of medicine, the active ingredients that may remain after two decoctions are more, so it can be decocted a third time and taken three times a day to save Chinese medicine resources and improve the therapeutic effect to a certain extent. 2.1 When taking Chinese herbal medicines, it is the habit of many people to decoct a dose of Chinese medicine twice and take it in the first and second juices respectively. In fact, this way of taking is not scientific. Because the active ingredients such as glycosides, polysaccharides and volatile oils that are easily soluble in Chinese herbal medicines are more in the first decoction, while other insoluble active ingredients are less in the first decoction; while in the second decoction, the active ingredients that are easily soluble may be very low in content, while the insoluble active ingredients are more in the second decoction, so the active ingredients in the two decoctions are not consistent and the efficacy of the medicine is also very different. Therefore, it is better to mix the first decoction and the second decoction and take them in 2 times in the morning and evening in order to bring out the best effect of the medicine. 2.2 There is also a certain amount of attention to the timing of taking herbal medicines. Generally speaking, tonic drugs and laxative drugs should be taken on an empty stomach before meals; drugs for treating external diseases and head and facial diseases should be taken after meals; drugs for calming the mind should be taken before bedtime; drugs 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.