Summary
A study found that nasal irrigation with low concentrations of hypochlorous acid can reduce allergic rhinitis symptoms, but it does not work better than saline nasal irrigation.
Key points
- Low-concentration hypochlorous acid (HOCl) nasal irrigation reduces allergic rhinitis symptoms.
- No significant side effects were observed with HOCl treatment.
- HOCl showed no additional benefit compared to saline nasal irrigation.
- Both HOCl and saline groups experienced similar improvements in symptoms.
Abstract
**Background: ** Low concentrations of hypochlorous acid (HOCl) have proven antipruritic, anti-inflammatory, and antimicrobial effects without toxicity, although the mechanism has not been fully elucidated.
**Objective: ** The aim of this study was to evaluate the effectiveness of HOCl nasal irrigation to reduce allergic rhinitis (AR) symptoms compared with saline nasal irrigation.
**Methods: ** This was multicenter, randomized, double-blind, placebo-controlled study. Initially, 139 patients with perennial AR were enrolled; however, 25 did not successfully complete the study. Patients were randomly assigned to the nasal irrigation with low-concentration HOCl (n = 55) or normal saline (n = 59) treatment groups for the 4-week study period. Participants completed the Rhinoconjunctivitis Quality of Life Questionnaire (RQLQ) at every visit (baseline, Weeks 2 and 4), and Total Nasal Symptom Score (TNSS) was determined before and after nasal irrigation every morning and evening.
**Results: ** We found that RQLQ scores significantly decreased after 4 weeks in the HOCl and placebo groups, but the decrement of the RQLQ score was similar between the 2 groups. Additionally, TNSS improved in both groups between baseline and Week 4, whereas there were no significant differences in the change of TNSS between the 2 groups. The HOCl group did not show any clinical side effects related to nasal irrigation.
**Conclusion: ** Allergic symptoms significantly decreased with low-concentration HOCl nasal irrigation, without significant adverse events. However, HOCl showed no additional improvement in symptoms compared with saline nasal irrigation for patients with perennial AR.
**Keywords: ** adult; allergic rhinitis; hypochlorous acid; nasal lavage; randomized controlled trial.