PREVIEW
Great-grandma was probably on the right track when she said, “A little dirt won't hurt you. It builds immunity.” In fact, some evidence suggests that our “hygienic” environment may be increasing our vulnerabilities to some maladies, especially allergic disorders. Although the principles of immunotherapy have been known for nearly a century, guidelines for its use are still evolving. In this article, Dr Portnoy discusses the role of immunotherapy in patients with symptoms triggered by airborne allergens.