Efficacy of Montelukast–Antihistamine Combination Therapy Versus Antihistamine Monotherapy in Allergic Rhinitis: A Systematic Review and Meta-Analysis

Objectives. Allergic rhinitis (AR) can substantially compromise daily functioning and well-being, and many patients require more than a single agent to obtain satisfactory symptom control. This study examined whether adding montelukast to antihistamine could manage AR symptoms and quality-of-life outcomes effectively. Methods. A review was performed in PubMed, Embase, Medline, Scopus, the Cochrane Library, and Google Scholar to iden-tify eligible studies reported through April 2025. Eligible studies compared combination therapy with montelukast plus antihistamine against antihistamine monotherapy and reported nasal symptoms or rhinoconjunctivitis quality of life questionnaire (RQLQ) scores. Treatment effects were further examined by antihistamine class. Results. Fifteen studies including 2,882 subjects were analyzed. Combination therapy significantly improved daytime nasal symptoms (standardized mean difference [SMD] [95% CI], 0.44 [0.21–0.67]), nighttime nasal symptoms (0.12 [0.01– 0.23]), and RQLQ scores (0.14 [0.00–0.27]) versus monotherapy. Individual nasal or ocular symptoms, sneezing, nasal obstruction, and rhinorrhea improved significantly, while nasal itching and ocular symptoms did not. Combinations with desloratadine and levocetirizine showed greater benefits than those with loratadine or fexofenadine. Conclusion. Montelukast–antihistamine combination therapy reduced overall symptoms and improved quality of life versus antihistamine monotherapy. The magnitude of benefit appears to vary depending on the specific antihistamine used, highlighting the possible value of individualized treatment strategies in the treatments of AR.