After a rise of adverse psychiatric reports on montelukast (Singulair), an oral leukotriene inhibitor used for asthma and allergies, the FDA added a black box warning in March 2020 about mood and behavior changes including suicide. There were 82 reports of completed suicide associated with the drug. Earlier research has linked montelukast to depression (odds ratio 7), aggression in children (odds ratio 30), and psychosis (Haarman MG et al, Pharmacol Res Perspect 2017;5(5):e00341). Given these risks, the FDA recommends reserving montelukast for serious symptoms that haven’t responded to other options.