201 - Feasibility and Practice of Amoxicillin/Penicillin Allergy Testing

Publication Number: 3193.201

Connor Montgomery, Connecticut Children's Medical Center, West Hartford, CT, United States; Jennifer L. Schwab, Connecticut Children's Medical Center, Rocky Hill, CT, United States; Matthew Shea, Connecticut Children's Medical Center, Hartford, CT, United States

Background: 10% of Americans report an allergy to penicillin, but only 1% are truly allergic. The use of alternative antibiotics incurs a greater risk of side effects, increased antimicrobial resistance, and greater cost.

Objective: To explore the feasibility and safety of amoxicillin allergy testing in a private pediatric practice.

Design/Methods: 395/5000 patients aged 2-23 years old in our practice have an amoxicillin/penicillin allergy documented. We sent a screening survey to these families. In addition, QR codes in exam rooms linked to the screening survey. Patients identified with an amoxicillin allergy were encouraged to scan the code and complete the survey. The survey included questions detailing how long ago it occurred, how soon it occurred after the medication was started, and the nature of the reaction. Patients with a history of erythema multiforme major, Stevens Johnson syndrome, DRESS syndrome, serum sickness, or any serious reaction within 24 hours of the first dose (including hives) were considered high-risk and referred to an allergist. Low-risk patients with reactions >6 months prior were assessed during a telehealth appointment and then tested in the office. Patients discontinued H2 blockers, antihistamines, antibiotics, and steroids 1 week prior to testing. Initial vital signs (VS) (BP, HR, %O2) were obtained prior to administering a 0.5 mL dose of 400mg/5mL amoxicillin. The patient was then observed for 15 min before undergoing a physical exam and another set of VS. The remaining 4.5 mL of amoxicillin was administered. After an additional 60 min, a provider performed a final exam and VS before determining if the allergy could be de-labelled. Patients were given a handout explaining that they were NOT allergic to penicillin/ amoxicillin. The exam room closest to the waiting room was used for VS and contained epinephrine, O2, and cetirizine. Patients waited in the waiting room and were instructed to notify staff if any reactions developed.

Results: 118 patients filled out the survey. 66 were scheduled for telehealth appointments, and 55 deemed eligible for in-office testing. Forty patients underwent in-office testing, and 39/40 passed. One child developed a single hive at 15 min, the testing was stopped and he was given cetirizine with no further progression of symptoms. Of the children who passed, 7 de-labelled patients have successfully taken amoxicillin with no reaction.

Conclusion(s): Screening for low-risk patients through a survey and a brief telehealth appointment allows for a safe and efficient in-office testing and de-labelling of pediatric patients diagnosed with penicillin allergies.

Amoxicillin & Epinephrine
PAS1.jpegAmoxicillin and epinephrine doses in the exam room. Epinephrine dosage is determined by the patient’s weight, which is obtained prior to administering amoxicillin.