Short description Cefixime is an antibiotic used to treat different types of bacterial infections. The drug can also be prescribed to treat other conditions. Before using Cefixime, it is imperative that you inform your doctor if you are allergic to penicillin or other antibiotics similar to Cefixime  such as Cerftin, Keflex and Omnicef.   Cefixime will not treat viral infections (flu or common cold).