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.

Penicillin Allergy Testing video.

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. 

Office Visits for Children Currently Experiencing Allergy Symptoms

Additional opportunities for the same or next day visits are provided for patients who are currently experiencing a reaction while taking an antibiotic. Many of these children go to the emergency room to be seen, with up to 40% of infants returning for a second visit within 24 hours if their condition has not improved. These children may now be seen at the PATS outpatient clinic either in person or by telemedicine.

Dr. Risma says, "Every day, patients come to the emergency room who are being treated with amoxicillin and have a rash like hives and perhaps lip or eye swelling. In the winter, it may be 2 or 3 patients a day, and they often return the next day with more concerns. We intentionally hold appointment spots open for patients who have an urgent need to be seen. Usually, caregivers simply need a clear plan for symptom relief, reassurance with the appearance of new symptoms, and information on how long the condition will last."

Learn more about serum sickness-like reactions (SSLR), in which the body’s immune system mistakenly identifies a substance (commonly an injectable medicine) as harmful.

Penicillin Allergy and Health Benefits of Challenging It

Young and Healthy podcast promo image.

Listen to the Cincinnati Children’s Young & Healthy Podcast episode about penicillin and penicillin allergy featuring guests Trisha Wendling, Nurse Practitioner and Tricia Earl, Clinical Care Coordinator, RN. 

Listen to the podcast

The Confusing Rash

Skin rash visible on a baby.

“Typically, patients will believe that they have a penicillin allergy because they develop a rash while taking it. But in pediatrics, we know that children can develop a rash for many reasons, and it may or may not be related to the antibiotic they are taking. If they are on an antibiotic, they have some kind of virus or bacteria that could be the cause for the rash. Also, children get rashes more easily than adults. It’s the way their bodies respond."

-  Trisha Wendling, DNP, APRN, CNP, nurse practitioner of the Drug Allergy Program. Follow the link to see Trisha's bio and patient reviews.  

Trisha Wendling.

The Urgent Need

An accurate assessment of penicillin allergy is important from a public health standpoint.

“As we use increasingly complicated antibiotics because of allergy labels, the price of healthcare goes up. It would be far better to take amoxicillin for a strep throat, ear or sinus infection than to take what we call “big gun” antibiotics that will, in most cases, cause diarrhea and increase the likelihood of bacterial resistance in the community.”

- Kimberly A. Risma, MD, PhD, leader of the Drug Allergy Program.