A 42-year-old member asked:
If i'm allergic to penicillin is it safe to take keflex pulvales?
1 doctor answer • 1 doctor weighed in
A Verified Doctoranswered
No: If you are truly allergic to penicillin, you should avoid all penicillin derivatives and the first generation cephalosporins. Keflex is a first gen. Cephalosporin and may cross react with penicillin. See a board certified allergist to help you determine if penicillin is a true allergy for you.
5.7k viewsAnswered >2 years ago
A 21-year-old member asked:
I'm allergic to penicillin, can I take keflex?
3 doctor answers • 12 doctors weighed in
Maybe: Penicillins (like amoxil) & cephalosporins (like keflex) are both beta-lactam antibiotics named because of their ringed chemical structure. Allergy to penicillins is sometimes directed against this ring, and an allergic reaction may also occur if a similar antibiotic is taken. It is estimated that about 10% of penicillin-allergic patients are also allergic to cephalosporins like keflex.
6.2k viewsReviewed >2 years ago
A 36-year-old member asked:
Is it a bad idea for someone allergic to penicillin safely take keflex, a cephalosporin?
1 doctor answer • 2 doctors weighed in
Allergy and Immunology 32 years experience
Yes: Cephalexin (keflex) is a first generation cephalosporin and a very close cousin to penicillin. Though it is not 100% true that all penicillin allergic individuals are also allergic to cephalexin, there is a high likelihood of that happening.
5.6k viewsReviewed >2 years ago
Last updated Oct 3, 2016
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