Low-concentration of hypochlorous acid (HOCl) in nasal irrigation was found to be safe and significantly relieved the symptoms of allergic rhinitis (AR), but had no extra improvement in symptoms than saline nasal irrigation for perennial AR patients, a study published in the American Journal of Rhinology & Allergy revealed.

Ho Chan Kim et al. compared the efficacy of HOCl and saline nasal irrigation to lower the symptoms of AR. A total of 139 patients were recruited in this multicenter, randomized, double-blind, placebo-controlled study but, 25 withdrew from the study. In this four-week study, subjects were divided into two groups: nasal irrigation with low-concentration HOCl (55 patients) or normal saline (59 patients) treatment groups.

At every visit (baseline, Weeks 2 and 4), the recruited subjects finished Rhinoconjunctivitis Quality of Life Questionnaire (RQLQ). Prior to and after nasal irrigation, the Total Nasal Symptom Score (TNSS) was ascertained every evening and morning.

As noted, the RQLQ scores substantially lowered following four weeks in the HOCl and placebo groups, although this decrease was comparable in both groups. Also, TNSS improved in both groups between baseline and end of the study period, but no significant change was found. No adverse effects were witnessed by people in the HOCl group.