Montelukast and neuropsychiatric events - a sequence symmetry analysis

Neuropsychiatric events (NEs) reported with montelukast during post-marketing surveillance by the US Food & Drug Administration resulted in a 2008 safety alert and a black box warning in 2020. Our objective was to evaluate montelukast exposure and NEs risk using sequence symmetry analysis.

National Veterans Health Administration (VHA) administrative data were used to identify 11 840 patients prescribed incident montelukast during fiscal year 2014. Incident prescribing of neuropsychiatric medication was used as a proxy marker for incident NEs and included antidepressants, benzodiazepines, hypnotics, antipsychotics, mood stabilizers, and buspirone. Symmetry ratios were calculated as the ratio of patients with an incident neuropsychiatric event in the year following montelukast initiation to the year preceding initiation. Exposure counterfactual analyses were used to examine the relationship between potential therapeutic alternatives to montelukast and risk for NEs.

Incident NEs were observed in 2305 patients following montelukast initiation and 2734 patients preceding montelukast initiation (SR 0.84, 95% CI 0.80-0.89). Sensitivity analyses examining each of the 6 sub-types of psychiatric medications also failed to show increased risk of NEs following montelukast initiation. Therapeutic alternatives to montelukast, such as inhaled corticosteroids, were also not associated increased NE risk.

Initiation of montelukast was not associated with increased risk of a variety of NEs in this sequence symmetry analysis involving adult patients in the VHA. Our findings do not support the hypothesis that NEs are associated with montelukast initiation.