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Rockville, MD
A 40-year-old female 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?

1 doctor answer2 doctors weighed in
Dr. Joram Seggev
Specializes in Allergy and 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.

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Last updated Jun 24, 2014

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