Efficacy of Prebiotics in Improving Clinical Outcomes of Allergic Rhinitis

Abstract

Introduction:
Allergic rhinitis (AR) is a chronic, IgE-mediated inflammatory disorder that significantly affects quality of life. Emerging evidence highlights the role of gut microbiota in immune modulation, suggesting that prebiotics may improve allergic outcomes by restoring microbial balance. This study aimed to evaluate the efficacy of prebiotic supplementation in improving clinical and immunological parameters in patients with AR.

Materials and Methods:
A prospective, randomized, double-blind, placebo-controlled study was conducted on 100 patients (18–55 years) diagnosed with AR as per ARIA guidelines. Participants were randomly assigned to receive either prebiotic supplementation (inulin + fructo-oligosaccharides, 5 g/day) or placebo for 12 weeks. Clinical assessment included Total Nasal Symptom Score (TNSS), Rhinoconjunctivitis Quality-of-Life Questionnaire (RQLQ), and Visual Analog Scale (VAS). Serum IgE, eosinophil count, and cytokines (IL-4, IL-5, IL-10) were measured pre- and post-intervention, and stool microbiota analysis was performed in a subset.

Results:
Prebiotic supplementation led to significant improvement in TNSS (8.2 ± 1.4 → 3.6 ± 1.3), RQLQ (4.9 ± 0.9 → 2.3 ± 0.8), and VAS (7.6 ± 1.1 → 3.1 ± 1.2) compared to placebo (p < 0.001). Serum IgE and eosinophil counts declined significantly (p < 0.001), with decreased IL-4 and IL-5 and increased IL-10 levels. Microbiota analysis revealed a marked rise in Bifidobacterium and Lactobacillus species. The intervention was safe and well tolerated.

Conclusion:
Prebiotic supplementation significantly improved clinical symptoms and immunological markers in AR, supporting its role as a safe, adjunctive, gut-targeted therapy.