Cephradine was compared to cephalexin a randomized, double-blind study for the treatment of bacterial infections in 162 children between four months and eleven years of age. In addition to evaluations of clinical and bacteriologic responses to therapy, the relative safety of the two cephalosporins was assessed for all children, including eight who were not included in the evaluation of drug efficacy. The children in the efficacy evaluation had either lobar pneumonia or skin infections and received oral suspensions of cephradine (25-110 mg/kg per day) or cephalexin (25-150 mg/kg per day) for five to fifteen days. Overall clinical and bacteriologic responses were nearly identical in the two groups, and both antibiotics proved to equally safe and effective for use paediatric practice.