Comparison of Adjunct Nasal Irrigation Therapy with Isotonic vs Hypertonic Saline Solution in Allergic Rhinitis Patients: A Double-Blind RCT Study

Nasal irrigation is widely recommended as an adjunctive therapy in allergic rhinitis (AR), but the comparative efficacy of isotonic versus hypertonic saline remains debated. This study aimed to evaluate their effects on symptoms, mucociliary clearance, and eosinophilic inflammation in patients with persistent AR. A randomized controlled trial was conducted in 40 AR patients, divided equally into isotonic and hypertonic saline groups. Irrigation was performed twice daily for four weeks. Outcomes included Visual Analog Scale (VAS) scores for rhinorrhea, nasal obstruction, sneezing, and itching and mucociliary clearance time (MCT) via saccharin transit test (assessed in week 2, 3, and 4), and nasal eosinophil counts (assessed in week 2 and 4). Friedman and Mann–Whitney tests were used for analysis. Both groups showed significant reductions in VAS scores for all symptoms from baseline to week 4 (p<0.001). The hypertonic group demonstrated greater improvements, with between-group differences becoming significant at week 4 for rhinorrhea (p=0.028), nasal obstruction (p=0.001), sneezing (p=0.002), and itching (p=0.010). MCT improved significantly in both groups (p<0.001), with superior outcomes in the hypertonic group at week 3 (right side, p=0.014) and week 4 (right, p=0.001; left, p=0.005). Eosinophil counts declined significantly within groups (p<0.001), but no significant intergroup difference was observed (week 2, p=0.918; week 4, p=0.454). Both isotonic and hypertonic saline irrigation effectively alleviated symptoms, improved mucociliary clearance, and reduced eosinophilic inflammation. Hypertonic saline provided superior improvements in VAS scores and mucociliary function, supporting its role as a more effective adjunctive therapy in AR management.