Anaphylaxis penicillin allergy causing

Allergy Cephalosporins cause a range of allergic reactions from skin rashes to anaphylactic shock. These reactions occur less frequently with cephalosporins than with penicillins. Complete cross-hypersensitivity between different cephalosporins should be assumed. Cross-reactivity between penicillins and cephalosporins is incomplete (5-10%), so penicillin-allergic patients are sometimes treated successfully with a cephalosporin. However, patients with a history of anaphylaxis to penicillins should not be treated with a cephalosporin. 

This concern isn t entirely theoretical penicillins, quiescent affinity label as mentioned above, cause allergies (mostly skin rashes and hives) in about 2% of the patients who take them, and even potentially fatal anaphylaxis in a few, and toxicity is believed to proceed through this sort of mechanism. With the current atmosphere about drug safety, it s no wonder that many companies will only consider working on irreversible inhibitors where the benefits clearly outweigh the risks as in the case of cancer, in the context of tool compounds, or perhaps not at all. Had penicillin been discovered today quite a few companies might choose not to develop it. 

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