- Each subject qualified by entry criteria history in a brief phone interview will be invited to come to a screening visit. A brief history and targeted physical exam to detect inclusion and exclusion criteria, listed below, will be performed after obtaining informed consent. Then, if the subject still appears eligible, they will undergo allergy skin testing to perennial ryegrass pollen extract as a key inclusion criteria. Skin testing will utilize standard prick techniques with appropriate saline/glycerin controls. The cross sectional measurements of the wheal and flare reaction will be recorded. A positive test will require a wheal >3mm vs the control diluent.