Zafirlukast is a leukotriene (loo-koe-TRY-een) inhibitor. Leukotrienes are chemicals your body
releases when you breathe in an allergen (such as pollen). These chemicals cause swelling in your lungs
and tightening of the muscles around your airways, which can result in asthma symptoms.
Zafirlukast is used to treat and prevent asthma attacks in adults and children as young as 5 years
old.
Do not give this medication to a child without a doctor's advice.
Zafirlukast may also be used for other purposes not listed in this medication guide.