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montelukast (Singulair)

Tradename: Singulair. Generic August 2012 [10] Indications: - prophylaxis & chronic treatment of asthma in adults & children over 2 years of age - adjunctive therapy for patients with asthma inadequately controlled on inhaled steroids [5] - exercise-induced asthma [7] - bronchospasm - seasonal allergic rhinitis in adults & children over 2 years of age [4] Contraindications: * considered safe in pregnancy [11] Dosage: 1) adults: 10 mg PO QD - 2 hours prior to exercise [7] 2) children age 2-5: 4 mg QD [3] Tabs: 4, 5 & 10 mg chewable tablets. Pharmacokinetics: - metabolized in liver by cyt P450 2C9 & 3A4 Adverse effects: 1) uncommon (< 2%) - asthenia, fatigue, dyspepsia, rash, fever, hypersensitivity 2) rare a) systemic eosinophilia b) Churg-Strauss syndrome 3) other - agitation, aggression, anxiousness, abnormal dreams, hallucinations, depression, insomnia, irritability, restlessness, tremor [9] - possible association between the use of Singulair & behavior/mood changes, suicidality (suicidal thinking & behavior) & suicide [8,9] - increased risk for neuropsychiatric disorder (RR=1.1) [13] - highest risk for anxiety disorder (RR=1.2) [13] * Boxed warning - serious behavior & mood-related changes [12] Toxicity: - no mortality in single doses of 5000 mg/kg in mice & rats. Drug interactions: 1) phenobarbital (no dose adjustment recommended) 2) any drug which inhibits cyt P450 2C9 or 3A4 can increase montelukast levels 3) any drug which induces cyt P450 2C9 or 3A4 can diminish montelukast levels Mechanism of action: leukotriene D4 receptor inhibitor

Interactions

drug adverse effects of leukotriene receptor antagonists

Related

allergic angiitis & granulomatosis of Churg-Strauss; eosinophilic granulomatosis with polyangiitis (EGPA) cysteinyl leukotriene receptor (LTC4 receptor, LTD4 receptor) cytochrome P450 2C9; cytochrome P450 BP-1; cytochrome P450 MP-4; S-mephenytoin-4-hydroxylase; limonene 6-monooxygenase; limonene 7-monooxygenase (CYP2C9, CYP2C10) cytochrome P450 3A4 (cytochrome P450 C3, nifedipine oxidase, P450-PCN1, NF-25, CYP3A4)

General

antiasthmatic agent leukotriene receptor antagonist

Properties

MISC-INFO: elimination route LIVER onset-of-action 1-2 MIN {IV} 1/2life 2.7-5.5 HOURS

Database Correlations

PUBCHEM correlations

References

  1. Merck & Company
  2. Prescriber's Letter 13(3): 2006 Cytochrome P450 drug interactions Detail-Document#: 220233 (subscription needed) http://www.prescribersletter.com
  3. Journal Watch 21(19):154, 2001 Knorr et al, Pediatrics 108:e48, 2001
  4. Singulair (Montelukast) for Seasonal Allergic Rhinitis Prescriber's Letter 10(2):9 2003 Detail-Document#: 190210 (subscription needed) http://www.prescribersletter.com
  5. Journal Watch 23(24):192, 2003 Bjermer L et al, BMJ 327:891, 2003 PMID: 14563743 http://bmj.bmjjournals.com/cgi/content/full/327/7420/891
  6. Department of Veterans Affairs, VA National Formulary - non formulary drug request
  7. Prescriber's Letter 14(7): 2007 Montelukast (Singulair) for Exercise-induced Bronchospasm Detail-Document#: 230707 (subscription needed) http://www.prescribersletter.com
  8. FDA MedWatch http://www.fda.gov/medwatch/safety/2008/safety08.htm#Singulair - Prescriber's Letter 15(5): 2008 Singulair (Montelukast) and Suicide Detail-Document#: 240507 (subscription needed) http://www.prescribersletter.com
  9. FDA Safety Alert 6/12/2009 Updated Information on Leukotriene Inhibitors: Montelukast (marketed as Singulair), Zafirlukast (marketed as Accolate), and Zileuton (marketed as Zyflo and Zyflo CR) http://www.fda.gov/Drugs/DrugSafety/PostmarketDrugSafetyInformationforPatientsandProviders/DrugSafetyInformationforHeathcareProfessionals/ucm165489.htm
  10. Prescriber's Letter 19(4): 2012 CHART: Anticipated Availability of First-Time Generics Detail-Document#: 280401 (subscription needed) http://www.prescribersletter.com - FDA News Release: Aug. 3, 2012 FDA approves first generic versions of Singulair to treat asthma, allergies http://www.fda.gov/NewsEvents/Newsroom/PressAnnouncements/ucm314436.htm
  11. Medical Knowledge Self Assessment Program (MKSAP) 17. 18, American College of Physicians, Philadelphia 2015, 2018.
  12. Brooks M FDA Adds Boxed Warning to Montelukast Over Mental Health Risks. Medscape - Mar 04, 2020. https://www.medscape.com/viewarticle/926271
  13. Paljarvi T, Forton J, Luciano S et al Analysis of Neuropsychiatric Diagnoses After Montelukast Initiation. JAMA Netw Open. 2022;5(5):e2213643 PMID: 35608857 Free article https://jamanetwork.com/journals/jamanetworkopen/fullarticle/2792596