The most important part of determining whether a child is allergic to a certain medicine (drug), such as antibiotics is through a careful and detailed history. In some cases the child may require skin and intradermal testing to help with the diagnosis. In the case of penicillin allergy, the majority of children will not be truly penicillin allergic, and based on the history the team will frequently offer observed doses of the penicillin based drug when seen in clinic. In other patients a formal supervised graded challenge will be more appropriate.