Bloodletting is one of the methods of acupuncture, which is the method of piercing the ligaments in the Internal Canon. According to different conditions, the superficial blood vessels in specific parts of the body are punctured with “three-pronged needles” to release the right amount of blood, which can activate the blood and regulate the qi to achieve the purpose of treatment. Ancient doctors attached great importance to bloodletting therapy, “Ling Shu Nine Needle Theory” said: “Therefore, for the treatment of needles, must tube its body and Feng Qi end, so that can be diarrhea heat bleeding and chronic disease exhaustion, …… main carbuncle heat bleeding.” “Suwen blood and gas form Zhi chapter” said: “Where the treatment of disease must first remove its blood.” The “Ling Shu Guan Needle Chapter” has even more “luo piercing”, “zan piercing”, “Bao Wen piercing” and other methods, although the needle tools are different, but all belong to the category of piercing the luo and releasing blood. It is said in Suwen’s treatise on malaria: “To prick a malaria, one must first prick the one whose disease starts first. For those who have headache and heavy headache first, first stab the head and bleeding between the forehead and eyebrows. For those who suffer from back and neck pain first, stab them first. If the pain in the lower back is first, stab the middle of the Qie and bleed first. For those who have arm pain first, first stab the hand Shao Yin and Yin Yang between the ten fingers; for those who have shin pain first, first stab the foot Yang Ming and bleed between the ten fingers.” The “Spiritual Pillar of Fever” says: “Heart hernia pain, take the foot Taiyin, Turk’s Yin all stabbing to remove its blood ligament” and so on not to mention. Not only this, but also shows that always combined with the doctrine of meridians, played a good role. Later generations of physicians have continuously enriched the content of bloodletting therapy in clinical practice. As contained in the “Thousand Gold Formula”: “The malaria of the stomach and the internal organs is also sick. Good hunger and can not eat, food and support full abdomen big. …… stabbing foot Taiyin, Yangming cross-loop bleeding.” Jin Yuan Zhang Zihe has: “eye disease head wind bleeding most urgent said” the monograph, discussing the understanding of the role of bloodletting and clinical application, widely circulated in folklore, and used by the general public. Ancestral medicine believes that disorders in the function of internal organs and disorders in the operation of meridians and blood are the root causes of diseases. Bloodletting therapy through the “regulation of blood and qi” to reach the meridians, so that the internal organs and qi and blood regulation, in order to restore the normal physiological function of the human body. The role of bloodletting therapy and the scope of application are mainly the following aspects: 1, the role of heat. Chinese medicine believes that there are two kinds of fever, one is Yang Sheng fever, one is Yin deficiency fever. The antipyretic effect of bloodletting is applicable to the former kind. Because Yang Sheng Sheng is bound to Blood Sheng, bloodletting can reduce Blood Sheng, thus reducing the evil heat in the blood vessels. The qi of the human body is based on blood, and at the same time goes in and out with blood, so releasing blood will inevitably remove the excessive yang qi, which changes the state of yang bloom and makes the qi and blood of the body normal. 2, pain relief effect. Traditional Chinese medicine believes that “the pass is not pain”, “pain is not pass”. This means that if a disease has painful symptoms, there must be a blockage in its meridians. Bloodletting therapy can directly bring out the stagnant evil in the meridians and adjust the blocked situation. In many clinical emergencies, such as sore throat and migraine, bloodletting therapy can be applied to get very good results quickly. 3, detoxification effect. By detoxification effect in Chinese medicine, it refers to the symptoms that occur when the organism is in pathological condition and cannot resist the poisonous evil due to its own dysfunction, such as “red silk boils” caused by hyperactive poisonous fire, and sores and carbuncles caused by the infiltration of poisonous evil. Bloodletting can not only make the poisonous evil invading the body expelled with blood, but more importantly, through the effect of “regulating blood and regulating qi”, the human body functions can be restored to normal to inhibit the expansion and regeneration of the disease evil. 4, the role of fire. Chinese medicine believes that the heart is the master of fire. If the heart fire is too hyperactive, the human body will show symptoms of fire, such as heart agitation, mouth and tongue sores, and even fever and delirium. Since the heart is the master of blood, bloodletting can directly reduce the symptoms of excessive heart yang, and achieve the effect of dipping the fire. Liver Yang is also known as “phase fire”, and the liver collects blood, so bloodletting can also treat hyperactive liver Yang and excessive phase fire. 5.Anti-swelling effect. Swelling and pain are mostly caused by stagnation of qi and blood, resulting in stagnation of meridians. Bloodletting can directly exclude the local meridians “Ivana Chen” of Qi, blood and disease, and promote the smooth flow of meridians, thus achieving the purpose of reducing swelling. 6.Anti-itch effect. The symptoms of itching are the manifestation of the presence of wind evil in the blood vessels, so there is a treatment principle of treating the wind first by treating the blood, and the wind will be extinguished when the blood flows. Bloodletting is to regulate the blood and regulate the qi, blood flow forcing the wind to stay, and to achieve the effect of dispelling wind and stopping itching. 7, stopping numbness. Qi deficiency can not be handsome blood to the four ends, then often appear numbness symptoms. The use of milli-needle puncture points on the affected limb to make a small amount of blood to treat numbness, is guided by the theory of blood flowing to the qi. 8. Anti-vomiting effect. Acute vomiting is mostly due to the incandescent heat of the stomach or liver Qi transverse to the stomach or food stagnation stagnation, bloodletting can diarrhea heat and calm liver rebellion, and has the effect of draining the stagnation of the intestines and stomach downstream. 9. Anti-diarrheal effect. The scope of bloodletting treatment for diarrhea, generally refers to the heat diarrhea caused by heat stagnation in the intestines and stomach, or epidemic epidemic, resulting in clear and cloudy diarrhea. The mechanism is to diarrhea fire and heat to achieve the effect of ascending clear and lowering turbidity. 10, the role of first aid. The so-called first-aid effect refers to the fainting and unconsciousness of the shutdown. Bloodletting can improve the condition of blood circulation, is a very good and effective rescue method. Bloodletting therapy has the characteristics of simple and inexpensive, and is popular among patients.