Allergen immunotherapy (AIT) is an effective treatment for allergic rhinitis. However, some people do not get the desired outcomes. The study’s goal was to look at the various elements that may influence the outcome of AIT, whether it was good or bad. A retrospective analysis was done on 1624 patients with allergic rhinitis who received AIT and 1519 matching patients who received just symptomatic treatment. Symptoms, medication ratings, and quality of life in relation to allergic illnesses were documented before and after therapy. A cluster analysis was done on all of the patients to see whether there were any correlations between response to therapy and the examined parameters. The Mailing criteria were used to measure treatment responsiveness. According to the Mailing criteria, a total of 1266 patients in the AIT group fulfilled the criterion of 30% or more improvement, and 1061 of these patients met the condition of 60% or greater improvement. Patients who had a consistently superior response to AIT were overrepresented in both clusters. There were patients with a recent history of allergic rhinitis and allergies to grass pollen or home dust mites. Patients having a lengthy history of allergic rhinitis before therapy, as well as polysensitization, were more commonly poor responders to AIT.

It is difficult to measure a person’s responsiveness to therapy, including AIT. Short-term allergic rhinitis and monovalent allergies to grass pollen or mites, on the other hand, were linked to a greater response to AIT.