The purpose of this study is to establish the rationale for the practice of performing an oral reintroduction test without previous skin tests in children at low risk of IgE-mediated reaction or drug-induced toxidermia, and to confirm the criteria for a drug reintroduction test could be performed without previous skin tests, without subsequent risk of reaction for the child. The primary endpoint will be the risk of a severe IgE-mediated or delayed hypersensitivity reaction in children who received beta-lactam drug reintroduction protocol prior to skin testing.

Inclusion Criteria:

• Children under 16 years of age coming for a consultation for a beta-lactam oral reintroduction test.

Exclusion Criteria:

• Refusal of the legal representatives of the subject for their child to participate in the study,
• If his age permits, refusal of the subject to participate in the study,
• Subject aged over 16,
• Pregnancy,
• Absence of affiliation of the subject to a social security scheme,
• Skin tests with incriminated beta-lactam already made before the consultation,
• Existence of contraindications to the realization of oral reintroduction drug test with the suspected antibiotic,
• Existence of criteria in the initial reaction suggestive of a non-low risk of IgE-mediated or delayed hypersensitivity to the incriminated beta-lactam, Taking antihistamine, corticosteroids or beta-blockers within 5 days prior to the oral reintroduction drug test,
• Travel abroad of the child scheduled within 7 days of the oral reintroduction drug test.

children under 16 years of age with a clinical history that is not suggestive of IgE-mediated anaphylaxis or toxiderma to beta-lactams.