Assessment of Suppression of Cutaneous Allergic Responses and Pruritus by Topical Doxycycline

This study is a cross-sectional survey to be completed in a single consecutive two day study visit.

To assess the effect of topical doxycycline 2% emollient cream or control emollient on immediate hypersensitivity allergy skin tests responses, pruritus, and associated late phase skin swelling.

Investigators will use generic Aquaphor, a skin protectant, as the control emollient. The active ingredient in this cream is Petrolatum 42%. Inactive ingredients include ceresin, lanolin alcohol, microcrystalline wax, mineral oil, phenoxyethanol.

Adults (ages 18-75 yrs) treated at the SUNY Downstate/UHB Allergy Faculty Practice with known respiratory (allergic rhinoconjunctivitis and/or asthma), and who have previously been evaluated and are allergen skin prick test (SPT) positive to common aeroallergens will, after five days of non-use of oral antihistamine therapy, undergo limited repeat SPT with the same documented positive allergens (up to 5 allergens per subject).

1. Allergen skin prick testing (Dermapik method) will be done on the volar surface of each forearm, with identical SPT allergens. The profile to be tested will be individualized, from 1-5- allergens, to be determined by previous skin test positive results. Volunteers for the study who have not been previously tested will also be eligible, provided they have a history of symptoms consistent with allergic rhinoconjunctivitis and/or asthma. These subjects will receive testing with a select panel of 5 mixed allergens - to include both perennial (cat, dust mite) and seasonal (tree, grass, ragweed).