According to Drugs.com, cefdinir is an antibiotic used for killing bacteria inside the body. It is a member of a group of drugs called cephalosporin antibiotics. Patients should notify their doctor if they are allergic to cephalosporin antibiotics, they have a kidney disorder or they've had an intestinal disease.
Cefdinir usually comes in the form of a liquid suspension, which may be stored for up to 10 days. Possible side effects include diarrhea, chest pain, flu symptoms, bleeding, seizures, jaundice, infrequent urination or loss of appetite. Drugs.com further mentions that those that experience diarrhea while taking cefdinir should not take anti-diarrhea medicine unless instructed to do so by their doctor.