ABSTRACT
Allergen-specific immunotherapy is the practice of administering gradually increasing quantities of an allergen extract to an allergic subject to ameliorate the symptoms associated with the subsequent exposure to the causative allergen. Allergen immunotherapy was introduced to treat “pollinosis” or allergic rhinitis by Noon and Freeman in 1911 (1). There is good evidence that immunotherapy using inhalant allergens to treat seasonal or perennial allergic rhinitis and asthma is clinically effective. Guidelines and indications for specific immunotherapy with inhalant allergens were published in 1998 by the World Health Organization (WHO) following several other guidelines (2) and updated in the Allergic Rhinitis and its Impact on Asthma (ARIA) document (3).
