Allergies are a significant health issue, yet few books exist on allergen tolerance of separation; here the author classifies allergen tolerance breakdown in specific types, according to the possibility that the autonomic breakdown of allergen tolerance in the unified airway depends on a deficit of pro-tolerogenic neurotransmitters at the local level. This paradigm, which explains the pathogenesis of allergic disorders, opens to new approaches to allergen-specific immunotherapy (AIT). While focusing on the new atopic disorders of the unified airway, such as local allergic rhinitis,  dual  allergic rhinitis, local allergic asthma, and local allergic conjunctivitis, the work combines clinical examples of allergic diseases and their treatment with their immunological background.