How long does it take for omnicef (cefdinir) to relieve the pain of strep throat. i have taken 2 days worth and am still in extreme pain?

Strep throat: True strep infections respond very quickly to antibiotics. Omnicef (cefdinir) dies treat strep infections therefore if you are still sick it seems possible you may have something else besides strep. Mononucleosis is a strong candidate if you are really tired and still sick. I would go back to the doctor and ask to check for other infections.