Researchers analyzed the medical records of 798,426 children born from 2001 to 2013 and found those who were prescribed antibiotics such as sulfonamide or macrolide, cephalosporin and penicillin during infancy had increased risks of being diagnosed with allergies, including food allergies, asthma or dermatitis later in childhood. The risk of developing an allergy was highest for children who received penicillin and lowest for those treated with sulfonamides, according to the study in JAMA Pediatrics.