What do you (pediatricians) (allergists) recommend for a 3 year old whose zpac isn't working to clear infection and is amoxcillan allergic ie hives?

May not need abx : It really depends on the site of infection. Generally Amoxicillin is still the drug of choice for non allergic culture positive strep throat and ear infections. Augmentin, (amoxicillin and clavulanate) which has Amoxicillin in it , would be drug of choice for sinus. Zpack usually does well with strep throat but not work for ears or sinus. The majority of infections are viral and need no abx. See your provider for next step.