Penicillin allergies may be linked to one immune system gene

People with self-reported allergies to the drug may have a vulnerability on the HLA-B gene

Penicillin allergy medic-alert bracelet

A medic-alert bracelet (one shown) signals a life-threatening reaction to penicillin. New research links penicillin allergy to an immune system gene.

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Penicillin, effective against many bacterial infections, is often a first-line antibiotic.