The Impact of Montelukast Duration on the Risk of Neuropsychiatric Disorders in Children with Asthma: A Population-Based Cohort Study

<b>Background/Objectives:</b> Asthma is one of the most common chronic diseases in children, and montelukast is widely prescribed to manage symptoms. However, concerns have emerged regarding its potential association with neuropsychiatric disorders. This study aims to investigate the impact of montelukast duration on neuropsychiatric risks in children with asthma. <b>Methods:</b> A cohort study was conducted using Taiwan's National Health Insurance Research Database (NHIRD), including children diagnosed with asthma between 2004 and 2007. A total of 14,606 children in the montelukast cohort and 8432 in the non-montelukast cohort were analyzed, with propensity score matching applied to reduce confounding bias. Neuropsychiatric outcomes, including Tics/Tourette's syndrome, were evaluated using Cox proportional hazard models. <b>Results:</b> Overall, montelukast use did not increase the risk of neuropsychiatric disorders. However, among children aged 6-15 years, prolonged use beyond 63 days was associated with a significantly elevated risk of Tics/Tourette's syndrome, with a 2.6-fold increase observed in girls and a 1.8-fold increase in boys. Conversely, shorter montelukast use in children aged 0-6 years was linked to a lower risk of neuropsychiatric disorders. <b>Conclusions:</b> Although montelukast generally does not elevate neuropsychiatric risks, extended use in older children may increase the likelihood of developing Tics/Tourette's syndrome. These findings highlight the importance of cautious prescribing in pediatric asthma management. Further research is necessary to validate these associations and inform clinical decision making.