Thiamphenicol is a derivative of chloramphenicol. It is a white odorless crystalline powder with a slightly bitter taste and is relatively stable to light and heat. It is soluble in water and methanol, slightly soluble in ethanol and acetone, and almost insoluble in ether and chloroform. The antibacterial spectrum of thiamphenicol is basically the same as that of chloramphenicol, with slightly lower antibacterial activity in vitro than chloramphenicol, but the opposite is true in vivo, with high and persistent blood drug concentrations. It is an antibacterial agent that has a bactericidal effect at high concentrations, and its mechanism of action is the same as that of chloramphenicol. Bacteria can also develop resistance to thiamphenicol and have complete cross resistance to chloramphenicol. Thiamphenicol is a strong immunosuppressive agent, with an effect about 6 times that of chloramphenicol. Oral and injection administration, absorption is rapid and complete. In normal individuals, oral, intramuscular, and intravenous injection of 500mg reach their peak blood concentration in 2 hours, 1 hour, and half an hour, respectively, lasting longer than chloramphenicol. It has little binding with proteins and can quickly penetrate into various tissues throughout the body. The content is higher in tissues such as the kidney, spleen, liver, and lungs, by the heart and muscles, and also distributed in brain tissues. Thiamphenicol is rarely metabolized in the body and does not bind to glucuronic acid in the liver, but is excreted in its original form from the urine. After oral administration of 500mg, the concentration in urine reaches up to 400 within 12 hours μ G/ml, the 24-hour excretion amount is about 50-70% of the administered amount, and thiamphenicol can also be excreted from the bile. The concentration in the bile is several times higher than the blood drug concentration. The clinical indications of thiamphenicol are the same as those of chloramphenicol. At first, people believed that the toxicity of chloramphenicol to the hematopoietic system was related to the nitro groups in its molecular structure. Thiamphenicol did not have nitro groups in its molecular structure. However, clinical observations have shown that Thiamphenicol can also cause inhibition of red blood cell formation, neutropenia, and thrombocytopenia. Therefore, regular blood tests are also necessary during use, but aplastic anemia rarely occurs during the medication process. The dosage for adults is 1-2g per day, and for children it is 25-50mg/kg, divided into 3-4 oral doses. The dosage of the glycine ester hydrochloride injection of thiamphenicol is the same as above.