Cephalosporin Allergy

Cephalosporin Allergy

Commonly Used Cephalosporins

  • Cefadroxil
  • Cefazolin
  • Cephalexin
  • Cefaclor
  • Cefoxitin
  • Cefprozil
  • Cefuroxime
  • Cefotaxime
  • Ceftriaxone
  • Cefixime
  • Ceftazidime

Cross Reactivity

Unlike the penicillins, cross reactivity between the cephalosporins is typically not a class effect. Cross reactivity in cephalosporins is primarily based on the similarities between the structures' side chains. Therefore, if a patient has a cephalosporin allergy, one can safely be given a different cephalosporin (or other beta lactam) that has dissimilar side chains.


Cefazolin does not share a side chain with any other beta lactam commonly used in Canada.

Please refer to the cross reactivity chart to determine if a cross allergy is possible between beta-lactams.