Ancef is part of the Cephalosporin Antibiotics class and treats Skin Infection, Bacterial Infection, Upper Respiratory Infection and other conditions. Cephalosporin antibiotics are used to treat ear infections, lower respiratory infections, upper respiratory infections, urinary tract infections, skin infections, pneumonia, and sinus Infections. They work by slowing the growth of the bacteria that is causing the infection. Ancef is only available as a brand name drug.