history or evidence of McCune Albright syndrome, immunodeficiency, mastocytosis, receipt of allergy shots, chronic skin disease, liver or kidney disease, cancer, neurological movement disorders, uncontrolled ADHD, evidence of eczema currently or in the past 2 years, history of anaphylaxis or anaphylactic like episode, evidence of pregnancy (by urinary hCG) or lactation, use of antihistamines 10 days prior to skin testing, use of systemic corticosteroids or tricyclic antidepressants 30 days prior to skin testing, presence of condition that would cause difficulty in adherence with study procedure.