Drug Allergy Program

Penicillin Allergy Testing

Getting Tested for a Penicillin Allergy

Recent studies have shown that it is safe to re-expose children to amoxicillin (a common penicillin) and that 95% of children who were thought to be allergic will not have a reaction when tested. The Penicillin Allergy Testing Services (PATS) at Cincinnati Children’s is available for patients admitted to the hospital or seen in outpatient clinic appointments.

For more information, call 513-517-7287 (PATS) or send an email to PATS@cchmc.org.

What is the testing like?

According to Kimberly A. Risma, MD, PhD, who leads the Drug Allergy Program, the testing is simple and safe and should be offered to all children who are labeled as having a penicillin allergy. Children may be seen when sick with an illness for which amoxicillin is the preferred antibiotic, receiving their first dose of amoxicillin in our office, or at a scheduled time when they are healthy. We test for an allergy to penicillin by giving a dose of amoxicillin by mouth and watching for a reaction. If there is not reaction, your child is not allergic.

What if my child is experiencing a rash today? 

Outpatient Testing

New patients coming to the PATS outpatient clinic will have penicillin testing done that same day in most cases. Patients take a dose of amoxicillin (the most commonly prescribed form of penicillin) at the beginning of the appointment, and our allergy staff observe them for an hour to make sure that there is no reaction. Rarely, staff may perform a skin test prior to administration of amoxicillin. After testing, PATS offers numerous supports, including access to allergy providers if you are concerned about allergic symptoms or have additional questions after the visit. Allergic symptoms during or after the challenge are uncommon (5% of children) and very mild.

Inpatient Consultations

Children labeled with penicillin allergy who are admitted to the Hospital Medicine Service will be offered the opportunity for allergy testing through PATS. If a patient is not on the preferred antibiotic for their infection because of a penicillin allergy, the patient may be evaluated and tested while the child is in the hospital. Testing will be offered Monday through Friday. Patients may also be referred for testing as an outpatient if the timing for amoxicillin challenge in the hospital is not ideal.