Taking cephalosporins on an empty stomach will not cause any significant adverse reactions. Taking antibiotics on an empty stomach will allow the antibiotics to stay in the gastrointestinal tract for a longer period of time and be more fully absorbed. But at the same time, it may also cause the drug to increase the damage to the mucous membrane of the gastrointestinal tract, so taking cephalosporins on an empty stomach may cause nausea, acid reflux, loss of appetite, stomach and abdominal fullness, and even stomach pain. It is recommended that cephalosporins be taken about half an hour to an hour after a meal to reduce the discomfort of the gastrointestinal tract after taking the drug. Some drugs require to be taken on an empty stomach, like drugs that inhibit gastric acid secretion, such as ranitidine and omeprazole, which require to be taken half an hour before a meal.