Alcohol is not recommended 4 days after cephalosporin injection and disulfiram-like reactions may occur with alcohol. Cephalosporin is an antibiotic that is mainly used for anti-infection treatment. After Cephalosporin enters the body, it will inhibit the ethanol dehydrogenase enzyme in the process of ethanol metabolism, so that the ethanol entering the body can not be metabolized normally, resulting in the accumulation of acetaldehyde and the occurrence of a disulfiram-like reaction, which can cause dizziness, headache, panic, blood pressure drop and other symptoms. Cephalosporin requires about 5 half-lives in the body to be completely metabolized and cleared, and the half-life of common cephalosporins varies from a few hours to a few days, with prolonged half-life in some cases of renal insufficiency. Inhibited ethanol dehydrogenase usually takes about 4 to 5 days to recover. It is generally recommended not to drink alcohol for 7-10 days after stopping the drug. In summary, after 4 days of cephalosporin injection, alcohol consumption is still not recommended, and if there is any discomfort, it is recommended to consult a doctor in time.