Intranasal Corticosteroids and Oral Montelukast for Paediatric Obstructive Sleep Apnoea: A Systematic Review

Background/Objectives: Paediatric Obstructive Sleep Apnoea (OSA) is characterised by recurrent episodes of upper airway obstruction during sleep, manifesting as snoring, intermittent oxygen desaturation, and frequent nocturnal awakenings. Standard treatments include surgical interventions, pharmacological therapies, intranasal corticosteroids, and oral montelukast. However, significant variability exists across studies regarding dosage and outcome assessment. This literature review systematically evaluated clinical evidence regarding the efficacy and safety of intranasal corticosteroids and oral montelukast for treating sleep-disordered breathing and its primary underlying condition, adenoid hypertrophy, in otherwise healthy children. Methods: The MEDLINE (PubMed), Scopus, and Web of Science databases were systematically searched up to 13 February 2025, using tailored search terms combining keywords and synonyms related to paediatric OSA, adenoidal hypertrophy, corticosteroids, montelukast, and randomised controlled trials. Owing to variability in outcome measures, Fisher’s method for p-value combination was employed to enable a comprehensive comparison of drug effects. Results: Available evidence shows that intranasal corticosteroids (mometasone, beclometasone, budesonide, fluticasone, and flunisolide), either as monotherapy or in combination with other agents, consistently lead to clinical and instrumental improvements in adenoid hypertrophy and related respiratory symptoms, with a generally favourable safety profile. Combining montelukast with intranasal corticosteroids appears to offer superior benefits compared with monotherapy. Nevertheless, the reviewed studies varied widely in dosage, treatment duration, design, and sample size. The reported side effects are mostly mild; however, long-term studies are lacking to establish the complete safety of these treatments in children. Conclusions: Intranasal corticosteroids and oral montelukast effectively and safely manage adenoid hypertrophy and mild-to-moderate OSA symptoms in children. Nonetheless, the heterogeneity of study designs necessitates larger prospective trials with standardised protocols and more extended follow-up periods to draw more robust conclusions. Future studies should aim to stratify treatment outcomes based on OSA severity and duration to tailor therapeutic approaches better.