International Rhinologic Society Rhinology 0300-0729 2026 04 02 High-dose steroid nasal spray is better than nasal irrigation in nonoperated chronic rhinosinusitis: a randomized clinical trial EN G.R. Lima Luz-Matsumoto inology Sector, Department of Otorhinolaryngology and Head and Neck Surgery, Federal University of São Paulo - Paulista School of Medicine, São Paulo, state of São Paulo, Brazil E. Cabernite Marchetti inology Sector, Department of Otorhinolaryngology and Head and Neck Surgery, Federal University of São Paulo - Paulista School of Medicine, São Paulo, state of São Paulo, Brazil L. Lobato Gregorio inology Sector, Department of Otorhinolaryngology and Head and Neck Surgery, Federal University of São Paulo - Paulista School of Medicine, São Paulo, state of São Paulo, Brazil F. Mesquita Callegari Department of Pathology, Federal University of São Paulo - Paulista School of Medicine, São Paulo, state of São Paulo, Brazil E. Macoto Kosugi Rhinology Sector, Department of Otorhinolaryngology and Head and Neck Surgery, Federal University of São Paulo - Paulista School of Medicine, São Paulo, state of São Paulo, Brazil Journal Article 3398 10.4193/Rhin24.532 BACKGROUND: To compare the efficacy of high-dose nasal steroid administered via high-volume irrigation versus spray delivery in patients with chronic rhinosinusitis (CRS) who have not undergone previous sinonasal surgery. METHODOLOGY: A double-blind randomized clinical trial was conducted. The study comprised two groups receiving 1,000 μg/day of nasal budesonide through two distinct methods over a 3-month period: irrigation and spray delivery. Patients with severe CRS who had never undergone surgery and were on the waiting list for surgery in a public health service were included. Primary outcomes included changes in quality-of-life scores and secondary outcomes included changes in clinical control questionnaire results and nasal endoscopy findings. Assessments were conducted on the total sample, CRS with nasal polyps (CRSwNP), CRS without nasal polyps (CRSsNP), and according to the newly defined phenotypes of diffuse primary CRS (central compartment atopic disease [CCAD], eosinophilic chronic rhinosinusitis [eCRS] and non-eosinophilic CRS [neCRS]). RESULTS: Sixth-seven patients completed the study, with 34 in the Irrigation Group and 33 in the Spray Group. The Spray Group demonstrated superior efficacy in improving endoscopic outcomes across the total sample, particularly among CRSwNP and CCAD. No treatment demonstrated superiority in improving the SNOT-22 score. Furthermore, the Spray Group revealed greater efficacy in reducing the number of uncontrolled patients, as evaluated by the clinical control questionnaire, both in the total sample and CRSwNP. CONCLUSIONS: High-dose steroid nasal spray outperformed high-volume steroid nasal irrigation in improving nasal endoscopy outcomes across the total sample, especially in CRSwNP and CCAD.