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A member asked:

Always fine w penicillin, but had extreme allergic reaction reaction to keflex! does that mean i am now also allergic to penicillin for sure?

A doctor has provided 1 answer
Dr. Joram Seggev answered

Specializes in Internal Medicine - Allergy & Immunology

Not necessarily: While penicillin and Cephalexin (keflex) share some features, allergy to one does not necessarily to one mean that you are allergic to the other. See a board-certified allergist/immunologist to sort things out.

Dr Parvez agreed

Answered 6/24/2014

4.5k views

Thank

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If I got an allergic reaction from cephalexin, does that mean I am also allergic to penicillin?

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