A review article in the Jan. 15 issue of JAMA on evaluation and management of penicillin allergy says that many patients report they are allergic to penicillin but few have clinically significant reactions. A comprehensive history of the reaction that led to allergy documentation can help determine the patients risk level.

• Low-risk history includes patients having isolated nonallergic symptoms, such as gastrointestinal symptoms, or patients solely with a family history of a penicillin allergy, symptoms of pruritus without rash, or remote (>10 years) unknown reactions without features suggestive of an IgE-mediated reaction.
• Moderate-risk history includes urticaria or other pruritic rashes and reactions with features of IgE-mediated reactions.
• High-risk history includes patients who have had anaphylaxis, positive penicillin skin testing, recurrent penicillin reactions, or hypersensitivities to multiple β-lactam antibiotics.