Powder injection is a powdery product formed by mixing drugs with reagents, sterilizing and drying. Convenient for transportation and storage. When powder injection is used, it is diluted with glucose solution, and the injection can be directly injected after being diluted according to different doses. Powder injection, as a dosage form, should be called "XX for injection", which can be divided into sterile powder and freeze-dried powder according to the principle of preparation. Such as: penicillin, cephalosporin, etc. This kind of powder injection is often aseptically packaged; Other antibiotics, such as gatifloxacin, a quinolone for injection, are freeze-dried powder. There are also differences in appearance between the two. Aseptic packaging is powder, while freeze-dried powder is often block. Both of them need aseptic workshop preparation. There are sterile powder and freeze-dried powder. Ordinary powder injection and solvent crystallization are just different in production technology.