The main aim of our study is to determine whether regular use of probiotics in patients with chronic rhinosinusitis helps improve their quality of life. Our main outcome of interest is a change in the mean score of the Sino-Nasal Outcome Test (SNOT-20) form in the treatment group and a greater change in the mean score of the SNOT-20 in the treatment arm as compared to the placebo arm. If probiotics are found to be effective, they may be used as a cost-effective, adjunctive therapy for patients with chronic rhinosinusitis.