Treatment of moderate to severe atopic disease may require multidrug regimens, reflecting the multifaceted nature of allergic inflammation. Furthermore, despite the central role of Th2 inflammation in allergic rhinitis (15), asthma (14), and atopic dermatitis (11), specific mediator antagonists may not be uniformly successful in the treatment of all atopic disorders. For example, antihistamines are very effective treatment for the symptoms of allergic rhinitis (41), but have minimal benefit in the treatment of asthma (42-44). Current research efforts are ongoing to identify and develop therapies aimed at critical junctures in the immunopathological process. For example, animal studies have suggested that IL-4 and IL-13 are two cytokines that are pivotal in the generation of airway allergic inflammation. Blocking the action of these cytokines may markedly decrease the allergic inflammation (17,125).