Desloratadine and levocetirizine improve nasal symptoms, airflow, and allergic inflammation in patients with perennial allergic rhinitis: A pilot study

Background: Nasal obstruction is the main symptom in patients with perennial allergic rhinitis. Some new antihistamines have been demonstrated to be capable of improving this symptom. Objective: The aim of this pilot study was to evaluate nasal symptoms, nasal airflow, eosinophils, and IL-4 in patients with perennial allergic rhinitis, before and after treatment with two new antihistamines: desloratadine and levocetirizine. Methods: Thirty patients with perennial allergic rhinitis were evaluated, 26 males and 4 females (mean age 26 ± 7.1 years). All of them received either desloratadine (5 mg/daily) or levocetirizine (5 mg/daily) or placebo for 4 weeks. The study was double-blind, parallel-group, placebo-controlled, and randomized. Total symptom score (including: rhinorrhea, nasal itching, sneezing, and nasal obstruction) was assessed before and after treatment. Rhinomanometry and decongestion test, nasal lavage, and nasal scraping were performed in all subjects before and after treatment. Eosinophils were counted by conventional staining; IL-4 was measured by immunoassay of fluids recovered from nasal lavage. Results: Desloratadine and levocetirizine treatment induced significant symptom relief and significant reduction of IL-4. Both antihistamines significantly affected all parameters in comparison with placebo. Conclusions: This pilot study demonstrates the effectiveness of antihistaminic treatment in: i) relieving nasal symptoms, including obstruction, ii) improving nasal airflow, iii) exerting decongestant activity, iv) reducing eosinophil infiltration, and v) diminishing IL-4 levels.