Study: Antibiotic Stewardship Means Probing When Patients Say They’re Allergic to Penicillin

Some 10% of patients will tell you they’re allergic to penicillin if the subject comes up, so you’d better give them something else if that’s what’s indicated for their diagnosis. The problem is, even those who believe what they’re saying are likely to be mistaken. As noted in an article just published in the Journal of the American Medical Association, less than 5% of the U.S. population actually has an allergy to penicillin. In this era of widespread—and dangerous—antibiotic resistance, it’s essential to understand what treatment options are available to you when treating patients with infection. Needlessly jumping past penicillin to a broad-spectrum antibiotic increases the risk for resistance and adverse events. The authors go so far as to say that responsible antibiotic stewardship, a concept that has been promoted vigorously in the urgent care setting, requires “evaluation of penicillin allergy before deciding not to use penicillin or other β-lactam antibiotics.” The text also reminds us that even true penicillin allergies often wane over time, and that serious reactions are thankfully rare. So, it may be advisable to probe further when a patient claims a penicillin allergy. Per the JAMA article, there’s moderate risk if the patient has a history of 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. Moderate-risk patients can be evaluated with penicillin skin testing, which carries a negative predictive value >95%, and nearly 100% when combined with amoxicillin challenge. In conclusion, the authors wrote, “Evaluation of penicillin allergy before deciding not to use penicillin or other β-lactam antibiotics is an important tool for antimicrobial stewardship.”