• See Also
  1. Leukotriene Receptor Antagonist
  2. Montelukast
  3. Zileuton
  1. Moderate Persistent Asthma
  2. Severe Persistent Asthma
  3. Aspirin-induced Asthma
  4. Exercise-Induced Bronchospasm
  5. Allergic Rhinitis
  • Dosing
  1. Avoid at mealtime
    1. Take 1 hour before or 2 hours after meals
  2. Dose
    1. Age >=12 years old: 20 mg orally twice daily
    2. Child 5-11 years old: 10 mg orally twice daily
  • Mechanism
  1. Attenuates bronchoconstriction and inflammation
  2. Leukotriene Receptor Antagonist (competitive inhibitor at D4 and E4 receptors)
    1. Similar to Montelukast (Singulair)
    2. Contrast with Leukotriene Synthesis Inhibitor (Zileuton or Zyflo)
  • Adverse Effects
  1. See Leukotriene Receptor Antagonist
  2. Nausea
  3. Hepatotoxicity risk
  • Efficacy
  1. See See Leukotriene Receptor Antagonist
  • Safety
  1. Pregnancy Category B
  2. Avoid in Lactation
  • Drug Interactions
  1. Zafirlukast increases other drug levels, potentiating their action
    1. Warfarin
    2. Theophylline
  2. Other drugs decrease Zafirlukast levels
    1. Erythromycin
    2. Theophylline
  3. Other drugs increase Zafirlukast levels
    1. Aspirin (high dose)
  • Resources
  1. Zafirlukast (DailyMed)
    1. https://dailymed.nlm.nih.gov/dailymed/lookup.cfm?setid=0262e192-94f4-423d-a58e-bb374dc106fe
  • References
  1. (2020) Drugs for Asthma, Med Lett Drug Ther 62: 193-200
  2. (1996) Med Lett Drugs Ther 38:111-2 [PubMed]
  3. (2000) Med Lett Drugs Ther 42:22-3 [PubMed]
  4. Scow (2007) Am Fam Physician 75:65-70 [PubMed]
  5. Wilson (2001) Chest 119:2021-6 [PubMed]