Neuropsychiatric side effects of montelukast: time to change prescribing practice?

Since 1998, montelukast has been licensed for the treatment of seasonal allergic rhinitis and asthma in people aged over 6 months. In children in particular, montelukast was welcomed as a steroid-sparing alternative to traditional asthma-preventer drugs, which could be taken just once daily, and which did not require the use of an inhaler. Although recent systematic reviews have shown regular inhaled corticosteroids (ICS) to be more effective than montelukast in controlling asthma symptoms, some children do demonstrate preferential response to montelukast.1 2 Consequently, current asthma guidelines still recommend montelukast as an optional alternative to ICS for mild-to-moderate asthma as monotherapy in children.3 While several studies and even prescribing information cite a wide range of potential neuropsychiatric side effects, the frequency of occurrence and exact nature of these side effects are not well defined and unfortunately not always well understood or recognised by healthcare professionals.4 In 2019 and then again in 2024, the UK Medicines and Healthcare products Regulatory Agency issued warnings and advice drawing attention to these problems.5 6 Similarly, in the USA, the Food and Drug Administration (FDA) issued a ‘black box warning’ for montelukast in 2020, drawing attention to documented mental and behavioural health risks associated with the use of the drug.7 More recently in 2024, the New York State district attorney called on the FDA to take urgent action to protect children from the risks of montelukast, including writing to …