The principles and methods of treating blood deficiency in TCM mainly include invigorating the spleen and regulating the stomach, invigorating qi and generating blood, tonifying kidney and generating blood, removing blood stasis and detoxifying and generating blood. (1) Strengthening the spleen and regulating the stomach, spleen and stomach are the source of blood biochemistry. If the diet is moderate and the spleen and stomach function is normal, blood production will naturally flow continuously. Therefore, the spleen and stomach must be strengthened first to replenish blood, and the source of biochemistry is endless if the spleen and stomach are strong. Commonly used prescriptions include Sijunzi Decoction, Siwu Decoction and Danggui Buxue Decoction. (2) The material basis of supplementing qi and producing blood is essence, while the promotion of essence into blood is driven by qi. In the Qing Dynasty, Li Zhongzi's "Required Reading for Doctors" said: "Blood and gas are essential, and qi is before blood; Both yin and yang are needed, and nourishing yang is above nourishing yin. " "Treatise on Epidemic Febrile Diseases" said: "Those who are good at blood do not seek tangible blood, but seek intangible qi." "Jing Yue Quan Shu" said: "It is difficult for tangible blood to grow quickly, but intangible qi should be urgently solidified." In clinical medication, according to "qi can generate blood", it is often used in blood tonic drugs, accompanied by qi-invigorating products. Commonly used prescriptions include Guipi Decoction and Danggui Buxue Decoction. Commonly used tonics include Astragalus membranaceus, Ginseng, Codonopsis pilosula, Atractylodes macrocephala, Polygonatum sibiricum, Dioscorea opposita, Jujube, etc. Combined with blood-nourishing drugs, such as Angelica sinensis, Radix Paeoniae Alba, Colla Corii Asini and Radix Rehmanniae Preparata. (3) Nourishing the kidney and generating blood is the innate basis, and it is the main source of storing essence. Essence includes both innate essence and acquired essence of internal organs. Essence can produce marrow, and marrow can transform blood. At the same time, the vital gate in the kidney is the origin of the original qi, the root of the twelve meridians and the source of biochemistry, and it is also the driving force for warming the heart and promoting blood biochemistry. Therefore, Chinese medicine has the saying that "blood production lies in the kidney". Clinically, to treat blood deficiency, it is necessary to tonify the kidney to replenish essence, and the essence is sufficient, and the blood is flourishing. Commonly used prescriptions are Cuscuta Cuscuta Decoction and Erxiandan. Commonly used kidney tonics include cornu Cervi Pantotrichum, colla cornus Cervi, colla Corii Asini, Colla Plastri Testudinis, Radix Morindae Officinalis, Herba Cynomorii, Herba Epimedii, Fructus Psoraleae, Semen Cuscutae, Radix Aconiti Lateralis Preparata, Cortex Cinnamomi, Polygoni Multiflori Radix, Radix Rehmanniae Preparata, Fructus Lycii and Placenta Hominis. (4) Removing blood stasis and generating blood, regardless of the nutrient blood of the spleen and stomach or the blood of the essence, must be released and transported through meridians and medullary channels and circulated throughout the body. The essence turns into blood, which is inherent in the nature, but nourished in the day after tomorrow. The subtlety of the valley and the essence of the five zang-fu organs also depend on the transport of meridians, which meet with the blood sea of the chong pulse to nourish the kidney and nourish the bone marrow. If qi and blood stagnate and pulse channels are blocked, bone marrow will be starved and dried up, resulting in blood biochemistry without reason. Commonly used prescriptions include Taohong Siwu Decoction, Buyanghuanwu Decoction, Xuefu Zhuyu Decoction and so on. Commonly used drugs for promoting blood circulation and removing blood stasis, such as Angelica sinensis, Chuanxiong, Salvia miltiorrhiza, Notoginseng Radix, Cortex Moutan, Rhizoma Cyperi, etc. (5) Detoxification and blood production Chinese medicine believes that no matter whether there are seven internal injuries or six exogenous diseases, stagnation for a long time can turn into fire, and fiery qi is the most likely to consume blood and hurt yin. Furthermore, chemical, physical, and biological pathogens sink into the liver and kidney, which can directly cause the lack of essence, resulting in passive blood production. Entrapment of pathogenic toxin or stagnation of fire in seven emotions can also block collaterals and cause blood stasis, so new blood is not born, so it is necessary to clear away heat and detoxify. Commonly used prescriptions include rhinoceros horn Dihuang decoction, Sanhuangshi ointment decoction, Yinchenhao decoction, Wuwei Xiaodu decoction, Qingying decoction, Qingwen Baidu decoction and so on. Commonly used antipyretic drugs include dandelion, honeysuckle, forsythia, Hedyotis diffusa, Radix Isatidis, Folium Isatidis, Rhizoma Coptidis, Scutellariae Radix, Cortex Phellodendri, Herba Violae, Radix et Rhizoma Rhei, Radix Arnebiae, Herba Artemisiae Scopariae, Herba Scutellariae Barbatae, etc. Clinically, it is mostly used for acute aplastic anemia, acute leukemia and hemolytic anemia.