Unable to host study at clinic site.

The purpose of this project is to identify clinic patients reporting penicillin allergy who are low risk for allergic reaction, and then invite them to participate in an oral amoxicillin challenge in their primary office without need for referral to allergy/immunology. If the patient is able to tolerate oral amoxicillin, the antibiotic allergy in question will be removed from the patient's chart.

Patients with a documented allergy to amoxicillin, ampicillin, or penicillin who are deemed low-risk for true penicillin allergy based on history will be offered enrollment in the study. Patients will be scheduled for an oral amoxicillin challenge in the primary care office at a later date. During this challenge, patients will be given 10% of a weight-based dose of amoxicillin and then observed for 30 minutes for signs and symptoms of an allergic reaction. If no reaction occurs, they will be given the remaining 90% of the weight-based dose and observed for an additional 30 minutes. Emergency medications such as diphenhydramine and epinephrine will be immediately available if needed. If the patient completes oral amoxicillin challenge without a clinically significant reaction, penicillin (and/or amoxicillin/ampicillin) allergy will be removed from the patient's chart.

Inclusion Criteria:

• Patients less than 18 years old who attend either of two hospital-affiliated general pediatric clinic sites who have an allergy to penicillin (or its derivatives) documented in their electronic medical record.

Exclusion Criteria:

• Patients who do not have an allergy to penicillin (or its derivatives) documented in their electronic medical record or patients with listed penicillin allergy whose parent/guardian declines to participate in the study. Patients will also be excluded if their penicillin allergy has been confirmed with either failed amoxicillin challenge or positive penicillin skin testing. Medically fragile children who cannot tolerate a direct oral challenge will be excluded but may be offered referral to allergy/immunology. If, on review of the history of the allergy, features of likely IgE mediated (onset in 1st hour of course or anaphylaxis requiring hospital care) or dangerous non-IgE mediated penicillin allergy (Stevens Johnson with penicillin, blistering rashes, penicillin related cytopenia) are obtained, these patients are also excluded from challenge but may be referred to allergy for further education and appropriate testing.