Taking Omnicef With A Penicillin Allergy - Walrus Health Both Omnicef and Cephalexin are drugs in a class known as cephalosporins They are NOT considered to be of the penicillin class although there is a SMALL chance of cross reactivity Current data suggest that the rate of cross-reactivity between penicillins and cephalosporins is probably less than 1%
Side Effects Of Amoxicillin And How Often They Occur - Walrus Health Taking Omnicef With A Penicillin Allergy Hello, my Dr has prescribed me Omnicef for a sinus infection that is being stubborn and I am allergic to penicillin I have previously taken cephalexin roughly 10 years ago with no side effects