Can taking singulair (montelukast) once a day stunt my growth?

No: I'm unable to find any data demonstrating that singulair (montelukast) negatively impacts growth. We see kids on this medication quite a bit. The growth issues for kids with asthma are related to the concomitant use of chronic oral corticosteroids and rarely the inhaled ones also. Chronic illness will impair growth, but if singulair (montelukast) keeps asthma in check it shouldn't be a growth concern by itself.