How long should Chinese medicine be boiled?

Most Chinese medicines are used for decoction, and decocting medicine is a science. Many people hold the Chinese medicine bags, but don’t know how to decoct the medicine correctly. Here I will teach you some common sense about decocting Chinese medicine. In fact, this is very particular. The quality of Chinese medicine decoction is closely related to the selected decoction device. It is still better to use a casserole now, because the material of the casserole is stable and will not react chemically with the drug ingredients. So, let’s take a closer look.

1. Selection of decoction utensils

Its heat transfer is uniform and gentle, which is one of the reasons why it has been used since ancient times. In addition, enamel pots, stainless steel pots and glass frying pans are also available. However, iron pots and copper pots cannot be used, mainly because the chemical properties of iron pots and copper pots are unstable and easily oxidized.

When decocting medicine, it can react with the chemical components contained in the traditional Chinese medicine. For example, it can react with tannin components to produce tannic acid iron, which deepens the color of the medicine solution. It can form incompatible polymers with flavonoids. It can form salts with organic acids. These will affect the quality of the decoction and are directly related to the clinical efficacy of the Chinese medicine decoction.

2. The amount of water added for decoction

The amount of water added when decocting medicine is also very important, as the amount directly affects the quality of the decoction. If too little water is added, the medicine will not be boiled thoroughly and the effective ingredients will not be completely extracted. If too much water is added, more medicine liquid will be boiled, which is very inconvenient for patients to take the medicine. Due to the different textures of Chinese medicinal materials, their water absorption capacity varies greatly, and the amount of water added is generally controlled at 5-10 times.

Medicines of the same weight will have larger volumes if they have loose texture, and will naturally absorb more water. The firmer the texture, the smaller the volume and the less water it absorbs. Therefore, when decocting flowers, leaves, and whole herbs, more water should be added. When decocting mineral and shellfish medicines, add less water. According to the traditional method of adding water, the medicine is placed in the pot. The amount of water added for the first decoction should be 3-5 cm above the surface of the medicine. The amount of water added for the second decoction should be 3 cm above the surface of the medicine. This method of adding water is simple, easy to operate and easy to master.

3. Matters needing attention in decocting medicine

1. Soaking before decocting: The medicine must be soaked before decocting. This is because most of the Chinese medicines derived from plants are dry products. Soaking in water can soften the medicinal materials, and the tissue cells will expand and return to their natural state, making it easier for the effective ingredients to be leached out during decocting. Generally, for medicines based on flowers, leaves and stems, the soaking time is 1-1.5 hours. The soaking time for medicines mainly composed of roots, seeds, rhizomes and fruits is 2-3 hours.

2. Number of decoctions: Multiple decoctions are more effective than one long decoction. Practice has shown that decocting a decoction twice can extract about 80% of its ingredients, so it is appropriate to decoct the medicine two or three times.

3. The temperature of decocting medicine: The temperature of decocting medicine is called "fire" in traditional Chinese medicine, and is generally called "gentle fire" or "strong fire". The so-called low heat is a weak fire, the temperature rises slowly, and the water evaporates slowly. The so-called high fire is a strong fire. The temperature rises quickly and the water evaporates quickly.

4. Decoction time: mainly depends on the nature of the medicine and the disease, as well as the condition of the medicine. Generally, the first frying takes 20-30 minutes from the start of boiling, and the second frying takes 30-40 minutes. For cold treatment medicines, the first decoction should be for 10-15 minutes and the second decoction should be for 15-20 minutes. For tonic medicines, the first decoction should be 30-40 minutes, and the second decoction should be 40-50 minutes.

5. The amount of retained medicinal liquid: generally refers to the amount of medicinal liquid after two decoctions of a dose of medicine. Adults take 400-600 ml, twice a day. Children take 200-300 ml, divided into two or three times a day.

6. Method of taking the medicine: Generally, a dose of medicine is decocted twice and then the liquid is combined and taken in two doses. Children can take it in 2-3 doses. Medicines for treating colds, fever, enteritis, and diarrhea can also be taken frequently, that is, take it every 4 hours, 30-40 ml each time. Stop taking it when the illness is cured, and then change to taking it 2-3 times a day. It is better for children to take small amounts and multiple times.

7. Decoction of special medicines: The doctor will prescribe medicines with footnotes in the prescription according to the patient's condition and the nature of the medicine.

(1) Decoction of the medicine first: Generally, some mineral, shell, or horn-shell medicines are hard in texture and the effective ingredients are not easy to extract. Generally, they need to be decocted for 30-40 minutes before being mixed with other medicines and decocted. Common ones include raw gypsum, raw dragon bone, mother of pearl, raw ochre, etc. In addition, toxic drugs should be decocted first, and long-term decocting can achieve the purpose of reducing or removing toxicity. For example, long-term boiling of aconite drugs can decompose aconitine into aconitine, whose toxicity is only 1/2000 of the original. For example, long-term decoction of aconite can not only reduce its toxicity but also increase its cardiotonic effect.

(2) Add the medicine last: Generally, the medicine should be aromatic and contain volatile oils or be difficult to boil for a long time. It should be put into the pot 10-15 minutes before the medicine is boiled. Common ones include Pogostemon cablin, Uncaria rhynchophylla, and Rhubarb. For example, the antihypertensive components of Uncaria rhynchophylla contained in Uncaria rhynchophylla will be easily destroyed if the cooking time exceeds 20 minutes. Rhubarb has a laxative and heat-clearing component, which is rhubarb glycoside, but it is unstable to heat and will decompose if heated for a long time. The laxative effect of rhubarb glycoside is stronger than that of aglycone, so it is not easy to decoct for a long time and is often added later.

(3) Packaged decoction: Generally, the seeds and individual pollen medicines are packed in gauze bags and put into the group of medicines for decoction. Common ones include Plantago seed, Inula flower, etc. For example, psyllium seeds tend to stick to the pan and become gelatinized and burnt. So it needs to be wrapped and fried. Decoction of Inula japonica can prevent the villi from falling off and mixing into the soup, which can irritate the throat.

(4) Dissolved medicine: Dissolve the medicine in hot liquid and then take it. Common medicines include Xuanming powder and Glauber's salt.

(5) Melt and take: mainly some gelatinous drugs, which are dissolved in hot liquid medicine and then taken. If the medicine is mixed and decocted, the viscosity of the medicine will increase, which will affect the extraction of other ingredients and there will be certain losses of gelatinous drugs. Therefore, the method of melting the medicine for oral administration is adopted. Common ones include raw donkey-hide gelatin, deer antler glue, and tortoise shell glue.

(6) Some precious medicines need to be decocted separately and then the liquid medicine is added to the medicine for consumption. Common ones include ginseng, American ginseng, deer antler, etc.

(7) Take with water. Some precious drug powders cannot be decocted together with other drugs. They are usually taken with water, that is, the powder is dissolved in the drug solution. This is beneficial to the effect of the medicine and can save medicinal materials. Common ones include Panax notoginseng noodles, antelope horn noodles, bezoar noodles, etc.

When decocting Chinese medicine, you need to pay attention to the selection of utensils, the amount of water added, the decocting time, the temperature, etc. Decocting Chinese medicine requires patience and carefulness. If you want to decoct a prescription of Chinese medicine, you must concentrate, so that you can decoct a good medicine.

Finally, the editor needs to tell you that if the fire is too strong when decocting the medicine, the water will evaporate quickly, which will affect the extraction of effective ingredients and easily cause the pot to burn. On the contrary, if the fire is weak, the effect of the decocted medicine will be poor. Generally, high heat is used before boiling, and then low heat is used after boiling. Keeping it in a slightly boiling state can slow down the evaporation of water, which is conducive to the extraction of effective ingredients.