It is also not allowed to drink after a day of taking cephalosporin, because cephalosporins need a certain amount of time to metabolize in the body, and the cephalosporin taken on the first day has not been completely metabolized in the body, at which time drinking cephalosporins reacts with alcohol in the body and a disulfiram-like reaction will occur. The chemical structure of most cephalosporin antibacterial drugs has a side chain of methiotetrazole, which can inhibit the activity of acetaldehyde dehydrogenase, causing the accumulation of acetaldehyde generated by the initial metabolism of alcohol and causing a disulfiram-like reaction, also known as drunkenness-like reaction. Some patients who drink small amount of alcohol after taking cephalosporin may experience flushing, headache, nausea, vomiting, shortness of breath, drop in blood pressure or even shock within 5-30 minutes, which can be relieved by themselves in mild cases but need to be resuscitated in emergency departments in severe cases. Therefore, drinking alcohol or drinks containing alcohol should be prohibited during the period of taking cephalosporins, and it is safer to drink alcohol after a week of stopping the medication.