Cephalosporin is a cephalosporin antibiotic, which is divided into five generations based on antimicrobial properties. Each generation of cephalosporin injections has a different potency and the time between infusions varies. It is important to inject the drug according to the patient’s own condition and under the monitoring of the doctor. The first generation of cephalosporin injection is more nephrotoxic and the fifth generation is expensive, so the second, third and fourth generation injections are used more often. 1. The representative drug of the second generation: cefuroxime sodium for injection, the common dosage for adults is 0.75~1.5g at a time, and the drug is given every 8 hours; when the condition is more serious, the drug is given 1.5g every 6 hours. 2. The representative drug of the third generation: ceftriaxone sodium for injection, the usual dosage for adults is 1~2g every 24 hours or 0.5~1g every 12 hours, maximum 4g a day, and 20~80mg/kg a day according to the body weight of children under 12 years old. 3. The fourth generation of representative drugs: cefepime hydrochloride for injection, components and children over 16 years of age or weighing 40 kilograms and above pediatric patients, the normal for each time 1 ~ 2 grams every 12 hours. If the infection is more serious can be given 2g every 8 hours. If patients need to inject cephalosporin, please consult a professional doctor, under the supervision of the doctor reasonable treatment.