Long-term efficacy of sublingual immunotherapy in patients with perennial rhinitis.

Background: Sublingual immunotherapy has a documented clinical efficacy, but only a few long-term studies have been performed in people with perennial rhinitis.

Objectives: The purpose of this study was to evaluate the long-term efficacy of sublingual immunotherapy.

Methods: One hundred thirty-seven patients with allergies to house dust mites were treated with sublingual house dust-mite-specific immunotherapy for 2 or 3 years and were also observed for 3 years after discontinuation of the treatment. The patients were divided into 2 groups: group A (67 patients) received active treatment for 2 years and then 1 year for placebo, and group B (70 patients) received active treatment for 3 years. The success of the treatment was evaluated with the symptom score, skin prick test results, and the nasal allergen challenge score.

Results: According to our study results, we found a greater improvement in the 3 years of sublingual immunotherapy compared with the 2 years of sublingual immunotherapy when we looked at the comparative results of the total 6 years.

Conclusion: We suggest 3 years of sublingual immunotherapy for patients with perennial allergic rhinitis who require immunotherapy and do not accept the subcutaneous route of allergen administration.