International Journal of Preventive Medicine (Int J Prev Med)2008-78021272021101825092509ENDepartments of Anesthesiology and Critical Care, AJA University of Medical Science, TehranDepartment of Infectious Disease, AJA University of Medical Science, TehranDepartment of Pharmacology, Faculty of Medicine, AJA University of Medical Science, TehranDepartments of Anesthesiology and Critical Care, AJA University of Medical Science, Tehran20211018Background: Nosocomial sinusitis is a common and less attended complication in patients admitted to intensive care units (ICU). It can cause several problems, such as prolongation of hospitalization, comorbidity, and mortality in patients. The present study aimed to evaluate the effect of azelastine (second‑generation antihistamine) and sodium chloride spray on sinusitis prevention in ICU admitted patients. Methods: In this randomized, open‑label, and parallel clinical trial a total of 126 patients were enrolled (63 patients per arm). Finally, 121 patients (61 patients in the control group and 60 patients in the treatment group) completed the study, and 120 patients entered the final analysis. In the treatment group, during 24 h after the insertion of nasogastric tube azelastine and sodium chloride sprays were administered (one puff from each spray every 12 h) while no intervention was conducted in the control group. Primary and secondary end‑points were evaluated within 10 days of the study period. Results: The incidence of sinusitis and pneumonia (18.3% and 16.6% in the control group compared to 8.3% and 3.3% in the treatment group, respectively) in the treatment group showed a decreasing trend; however, only the difference of pneumonia was statistically significant between groups (P = 0.03). In addition to the clinical pulmonary infection score, nasal and tracheal secretions were significantly improved in the treatment group (P = 0.03, P < 0.001, and P = 0.01, respectively). Conclusions: The findings of the present study offer an inexpensive, low‑risk, and efficacious intervention for the prevention of upper respiratory tract infections in ICU patients.http://ijpm.mui.ac.ir/index.php/ijpm/article/view/2509http://ijpm.mui.ac.ir/index.php/ijpm/article/download/2509/717718350