Traditional Chinese medicine (TCM) is one of the basic methods of traditional Chinese medicine treatment. The process of decoction is complex, and the time, heat, and utensils used for decoction have a great influence on the efficacy of the herbs. Most of the Chinese herbs need to be decocted before taking them, but many people are not familiar with the correct method of decoction. Let's learn how to decoct Chinese herbs correctly.
1. Soaking before decoction
Generally, soak the herbs in cold water until they are fully soaked before decoction, so that the active ingredients are easier to extract. Soaking for about 30 minutes is usually sufficient, but it should also be treated differently based on the texture of the herbs, the season, temperature, and other factors. Flowers, grass, and leaves can be soaked for 20 minutes; rhizomes, seeds, fruits, minerals, and shellfish herbs should be soaked for 30-60 minutes. In general, the herbs should be fully soaked.
2. Choice of decoction utensils
The choice of decoction container is closely related to the quality of the decoction. Historically, it is believed that "silver is the best, followed by ceramics." It is not recommended to use pots made of tin, iron, and other metals for decoction. Some herbs may precipitate or undergo chemical changes when they encounter tin, iron, and other metals, reducing their solubility and causing side effects. Currently, it is recommended to use ceramic or earthen pots instead of iron or copper pots. It is also best not to use aluminum pots, stainless steel, or enamel containers for decoction to ensure the efficacy of Chinese herbs.
3. Choice of decoction water
Water is the most commonly used solvent for decocting Chinese herbal medicine. Clean cold water such as tap water, well water, and distilled water should be selected. The amount of water used should be determined based on factors such as the weight, volume, water absorption capacity of the herbs, decoction time, heat, and required dosage. Generally, the water should cover the herbs by about half an inch. The amount of water used for decoction should be sufficient at once, without adding water multiple times in the middle. The dried herbs should be discarded and not re-decocted with water.
4. Degree of heat for decoction
Decoction of Chinese herbs can be divided into "strong heat" and "gentle heat". Generally, start with strong heat and switch to gentle heat after boiling. Different formulas require different decoction times. The decoction time for treating exterior syndrome with sweating herbs should be short, while the decoction time for treating deficiency syndrome with tonifying herbs should be long.
5. Proper administration
The decoction should be taken about an hour before meals. Medications that may irritate the gastrointestinal tract should be taken after meals. Tonifying herbs should be taken on an empty stomach, sedative herbs should be taken before bed, and chronic diseases should be taken at regular intervals. Generally, one dose should be divided into 2-3 administrations per day. If necessary, two doses can be taken in one day to enhance the efficacy. Chinese herbal decoctions should be taken warm, but depending on the specific situation, they can also be taken cold.
6. Avoidance of contraindications
TCM has long-standing contraindications. Therefore, folk remedies and secret formulas should not be used blindly, and one should not act as a self-taught doctor. It is necessary to formulate and prepare herbs under the guidance of a doctor. For example, certain medications have side effects that can harm the fetus or even cause abortion, so they should be considered contraindicated during pregnancy, such as croton, morning glory, rhubarb, blister beetle, musk, three edgewise, curcuma, and leeches. Medications that should be used with caution during pregnancy include peach kernel, safflower, rhubarb, aurantium, aconite, dried ginger, and cinnamon.
7. Avoidance of certain foods during medication
During medication, it is necessary to avoid foods that are difficult to digest or have irritating properties, such as raw and cold foods and strong-smelling foods. In addition to the common restrictions such as avoiding onions, garlic, and radishes when using Rehmannia and Polygonum multiflorum, crab meat when using Poria cocos, and raw onions when using honey, specific dietary restrictions should also be followed based on the specific condition and doctor's advice.
8. Why cover the pot when decocting herbs
Some people often do not cover the pot when decocting herbs for convenience. In this regard, TCM practitioners remind patients not to forget to cover the pot when decocting herbs.
According to research, the majority of plant-based Chinese herbs, such as Magnoliaceae, Rutaceae, Asteraceae, contain volatile oils. Volatile oils have functions such as dispelling wind, antibacterial, anti-inflammatory, and analgesic effects in medicine. However, the solubility of volatile oils in water is very small, and the majority of volatile oils have a lower density than water, so they easily evaporate with the steam. If the pot is not covered during decoction, the active ingredients in the herbs can easily "run away" with the steam, reducing the efficacy of the medication.
9. How to control the decoction time
The decoction of Chinese herbs requires attention to the heating power and duration of the decoction. The mastery of heat should also be based on the nature of the herbs. Herbs for treating exterior syndrome have a fragrant aroma and mostly contain volatile oils. Prolonged decoction can cause excessive evaporation, so it is generally recommended to use strong heat for a short decoction time. The initial decoction should be boiled for 15 minutes, and the second decoction should be boiled for 10 minutes. Tonifying herbs have a heavy and nourishing nature, and they require a long decoction time to extract the essence. It is generally recommended to use strong heat for boiling and then switch to gentle heat for decoction. After the initial decoction is boiled, it should be simmered for 20-30 minutes, and after the second decoction is boiled, it should be simmered for 30-40 minutes. For herbs with long decoction times, they should be stirred 2-3 times during decoction to prevent the herbs at the bottom from scorching. It is not appropriate to accidentally burn the herbs and then add water to decoct them again, as this may cause a qualitative change in the herbs.
10. Longer decoction does not mean stronger concentration
In daily life, most people believe that the longer the decoction of Chinese herbs, the stronger the effect. They think that a longer decoction time means more active ingredients. However, this is not true. Decoction of Chinese herbs is a process of continuously releasing and dissolving the active ingredients in the herbs. When the concentration of active ingredients in the herbs reaches a balance with the decoction liquid, the process stops. Continuous decoction will not continue to dissolve the active ingredients in the herbs, but instead evaporate and reduce the amount of active ingredients in the decoction, and may even damage the active ingredients at high temperatures, leading to a decrease in efficacy.
Therefore, it can be seen that longer decoction time does not mean better. Different prescriptions have different time requirements after boiling, and they should be followed according to the doctor's instructions.
11. Do not wash the herbs before decoction
The herbs should not be washed before decoction. This is because:
1. Washing with water can cause the loss of water-soluble components of the herbs: Many herbs contain sugars and glycosides that can dissolve in water. After washing with water, a part of the active ingredients will be lost, leading to a decrease in efficacy.
2. Washing can cause the loss of powdered herbs: Many Chinese herbs are in the form of powder, and some require grinding during preparation, such as peach kernel, dragon bone, talcum powder, etc. Washing with water will cause the loss of these herbs.
3. Washing can cause the loss of certain auxiliary materials: Some herbs require the addition of honey, alcohol, bile, and other auxiliary materials during processing, and these auxiliary materials are easily soluble in water. If washed with water, some auxiliary materials may be lost, such as bile arisaema and wine-processed rhubarb commonly used in Chinese herbs.
Therefore, it is not advisable to wash the herbs with water before decoction to avoid the loss of herbal components and the impact on the efficacy of the medication.
12. Discard the decoction if it becomes thick
The effectiveness of Chinese medicine lies in its active ingredients such as alkaloids, saponins, and tannins. The purpose of decoction is to extract the active ingredients from the herbs to facilitate the treatment of diseases.
The method of decoction has a great influence on its efficacy. If the decoction time is too short, the active ingredients may not be fully extracted, affecting the therapeutic effect. If the decoction time is too long, it can cause the destruction or loss of active ingredients (such as volatile components), and it can also make the decoction thick. Once the Chinese medicine becomes thick, its properties will change. For example, the taste of tonifying herbs will change from sweet to bitter, and they will no longer have a tonifying effect. Blood-activating and stasis-resolving herbs will become herbs with hemostatic effects. After becoming thick, most of the active ingredients in the Chinese medicine will be destroyed or have the opposite effect. Therefore, the decoction should be discarded if it becomes thick.
