Montelukast‐Induced Anxiety in Two Pediatric Patients

Montelukast, a leukotriene receptor antagonist, is approved by the United States Food and Drug Administration (FDA) for the prophylaxis and long‐term treatment of asthma, prevention of exercise‐induced broncho‐constriction, and symptomatic relief of allergic rhinitis. In the literature, anxiety has been reported as being related to montelukast only in a retrospective analysis of clinical trial data and in surveillance studies. However, montelukast was associated with anxiety in 421 postmarketing MedWatch adverse event reports received by the FDA between 1998 and 2009. In 2009, a precaution was added to montelukast's package labeling regarding anxiety and other neuropsychiatric adverse events. We describe two pediatric patients with anxiety that manifested during montelukast therapy. The first patient was a 4‐year‐old, 16‐kg boy who experienced anxiety and sleep disturbances within 5 months of starting montelukast 4 mg at bedtime, which subsequently resolved 2 weeks after drug discontinuation. The second patient was a 6‐year‐old, 16.6‐kg girl who developed anxiety 3 weeks after her montelukast dose was increased from 4 mg to 5 mg at bedtime. Her symptoms resolved, without recurrence, within 4 weeks after the dose was reduced to the previously tolerated lower dose. Use of the Naranjo adverse drug reaction probability scale indicated a possible (score of 3 [first patient]) and probable (score of 8 [second patient]) relationship between these patients' development of anxiety and montelukast therapy. Health care professionals should be aware of the potential for neuropsychiatric adverse effects with montelukast and should assess the need for continued therapy if anxiety is reported.