5-Aminosalicylic Acid and omnicef

17 months old daughter, with ear infection has taken Omnicef before (with no side effects) but yesterday was given the first dose of Omnicef, and today morning she has big red rash like blotches all over her body and its still spreading. She is now,fussy and does not want to be clothed (my guess is because of the terrible itching!). The rash spreaded allover her face and body and more concentrated on ankles and hands. Dr. said discontinue the Omnicef and see what happens in a day or two. ( I guess I need to stop the terrible medicine and may be stop seeing this Dr., too!)