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Houma, LA
A 18-year-old male asked:

Cephalexin side effects and safety? allergic reaction risk?

2 doctor answers3 doctors weighed in
Dr. Mohammed Parvez
A Verified Doctoranswered
Internal Medicine 16 years experience
Urticaria: Cephalexin is an oral antibiotic, belongs to the class of 'cephalosporin'. People who are allergic to 'penicillin" in general, will have cross sensitivity reaction to cephalosporin as well. The drug reaction can vary from mild urticarial rash to severe anaphylaxis, which will be life a threatening situation. Sometimes cephalosporin can give 'drug induced fever' as well. Good luck !
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Dr. Martin Raff
Dr. Martin Raff commented
Infectious Disease 58 years experience
Actually less than 5% of people with documented allergies to penicillins are allergic to cephalosporins and less than 0.5% of those will have anaphylaxis or urticaria (this also being a manifestation of immediate hypersensitivity). Any medication can produce allergic reactions. The major side-effect here is failure to absorb the drug or gastrointestinal intolerance.
Aug 1, 2013
Dr. Martin Raff
Infectious Disease 58 years experience
Very safe: Minimal side-effects. Can be allergic and manifested by the usual spectrum of allergic reactions to any medications. If you have a predeliction to allergies this may occur.
Created for people with ongoing healthcare needs but benefits everyone.
Last updated Jun 24, 2014


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