Abstract
The possibility of producing local hyposensitization by administering allergens via mucosal routes was envisaged at the beginning of 1900, and local nasal immunotherapy has been extensively studied since the 1970s. Presently, there are 21 randomized controlled trials being conducted with the most common allergens, consistently showing the clinical efficacy of local nasal immunotherapy for rhinitis. Other advantages are that it has an optimal safety profile and can be self-administered at home by the patient. Moreover, there are several data from animal models and from humans that confirm the immunomodulatory effect of intranasally administered antigens. On the other hand, local nasal immunotherapy seems to be effective only on rhinitis symptoms and requires a particular technique of administration. For these reasons, its clinical use is progressively declining in favour of the sublingual route although nasal immunotherapy is validated in official documents and remains a viable alternative to injection.