Morning Versus Evening Administration of Intranasal Mometasone Furoate in Seasonal Allergic Rhinitis: A Baseline-Adjusted Comparative Study

Objective: To compare the effects of morning versus evening once-daily administration of intranasal mometasone furoate on nasal symptoms, sleep quality, daytime sleepiness, and quality of life in patients with moderate-to-severe seasonal allergic rhinitis (SAR). Methods: This prospective, randomized, single-blind study included 120 adults with SAR who received intranasal mometasone furoate (200 μg once daily) either in the morning or in the evening for 15 days. Outcomes were assessed using the Total Nasal Symptom Score, Rhinitis Quality of Life Scale, Pittsburgh Sleep Quality Index, and Epworth Sleepiness Scale. Baseline-adjusted comparisons between treatment groups were performed using analysis of covariance. Results: Both treatment groups showed significant posttreatment improvements in nasal symptoms, sleep quality, daytime sleepiness, and rhinitis-related quality of life. After adjustment for baseline values, no statistically significant differences were observed between morning and evening dosing for any outcome measure (all P > .05). Baseline disease severity emerged as the primary determinant of posttreatment outcomes, accounting for a substantial proportion of outcome variability, whereas dosing time showed no clinically meaningful effect. Conclusion: Once-daily intranasal mometasone furoate provides comparable clinical benefits regardless of whether it is administered in the morning or in the evening in patients with moderate-to-severe SAR. These findings suggest that dosing time has limited clinical relevance for long-acting intranasal corticosteroids, allowing treatment to be guided by patient preference without compromising efficacy.