Published online: March 30, 2017
About 7% of the United States population thinks they are allergic to penicillin. Less than 5% of the 7% truly are. It is well known than individuals who carry a penicillin allergy label, even if unconfirmed, will be exposed to alternative broad-spectrum antibiotics that have much more severe side effects, such as killing off important protective bowel bacteria and causing Clostridium difficile. Previous studies have shown that penicillin allergy testing is safe and has many short-term benefits, such as enabling the use of less expensive narrow-spectrum penicillins when needed. The long-term benefits of penicillin allergy testing and the effects it has on overall healthcare use, until now, have been unproven.
In a recent article published in The Journal of Allergy and Clinical Immunology: In Practice, Macy and Shu reported on a group of 308 individuals with a history of penicillin allergy who were penicillin allergy tested between 2010 and 2012. A very well matched group of 1251 individuals with history of penicillin allergy, who were not penicillin allergy tested, was then selected. Both groups were then followed for all inpatient and outpatient clinical care used over a 3.6-year period. All antibiotic use and all new antibiotic-associated side effects were also recorded.
Patients who had penicillin allergy testing had significantly fewer out-patient visits and spent on average about ½ a day less in the hospital during every year of follow-up. Tested patients were more likely to get narrow-spectrum penicillin and first generation cephalosporins. Tested patient were less likely to get clindamycin or macrolide antibiotics. Because the use of broad-spectrum antibiotics, which are associated with more side-effects, was reduced, penicillin allergy testing these 306 individuals saved about 2 million dollars in health care expenses over the 3.6-year follow-up period, mostly accounted for by fewer days in the hospital.
Penicillin allergy testing benefits patients by showing them they can safely use narrow-spectrum penicillin when needed. Penicillin allergy testing benefits society by helping save money that otherwise would have been spent on avoidable healthcare. Penicillin allergy testing continues to pay benefits to both patients and society at large over at least a 3.6-year follow-up period. Penicillin allergy testing aids antibiotic stewardship efforts and help prevent the development of antibiotic resistant bacteria, because more appropriate narrow-spectrum penicillins are used.
The Journal of Allergy and Clinical Immunology: In Practice is an official journal of the AAAAI, focusing on practical information for the practicing clinician.