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.