Indications/Uses
Listed in Dosage.
|
Dosage/Direction for Use
Adult : PO Chronic asthma; Allergic rhinitis 10 mg once daily. Prophylaxis of exercise-induced asthma 10 mg to be taken 2 hours prior to exercise; no additional doses to be taken within 24 hours.
|
Dosage Details
Oral
Prophylaxis of exercise-induced asthma Adult: As film-coated tab: 10 mg to be taken 2 hours prior to exercise; no additional doses to be taken within 24 hours. Child: 2-5 years As granules or chewable tab: 4 mg; 6-14 years As chewable tab: 5 mg; ≥15 years Same as adult dose. Doses to be taken 2 hours prior to exercise; no additional doses to be taken within 24 hours. Evaluate patient after 2-4 weeks of treatment. Oral Allergic rhinitis Adult: As film-coated tab: 10 mg once daily (taken in the evening for asthmatic patients; for nonasthmatic patient, doses may be taken either in the morning or evening). Child: ≥15 years Same as adult dose. Oral Chronic asthma Adult: As film-coated tab: 10 mg once daily in the evening.
Child: 6 months-<2 years As granules: 4 mg once daily. 2-5 years As granules or chewable tab: 4 mg once daily; 6-14 years As chewable tab: 5 mg once daily; ≥15 years Same as adult dose. All doses to be taken in the evening. Evaluate patient after 2-4 weeks of treatment. |
Special Precautions
Aspirin-sensitive asthmatic patient must continue avoiding aspirin and other NSAIDs. Not intended for treatment of acute asthma attacks. Not recommended as monotherapy in treatment of moderate chronic asthma. Avoid abrupt substitution to oral or inhaled corticosteroids. Children. Pregnancy and lactation.
|
Adverse Reactions
Significant: Behavioural changes (e.g. agitation, anxiety, depression, dream abnormalities, obsessive-compulsive disorder). Rarely, systemic eosinophilia, vasculitis with eosinophilic granulomatosis with polyangiitis (Churg-Strauss syndrome).
Ear and labyrinth disorders: Otalgia, otitis media. Eye disorders: Myopia, conjunctivitis. Gastrointestinal disorders: Diarrhoea, nausea, vomiting, abdominal pain, dyspepsia, gastroenteritis. General disorders and admin site conditions: Pyrexia. Infections and infestations: Viral infection, tooth infection. Investigations: Elevated serum transaminase levels (ALT, AST). Nervous system disorders: Headache, drowsiness, dizziness. Respiratory, thoracic and mediastinal disorders: Upper respiratory tract infection, cough, acute bronchitis, influenza, laryngitis, pharyngitis, rhinorrhoea, sinusitis, sinus headache, pneumonia. Skin and subcutaneous tissue disorders: Rash, atopic dermatitis, eczema, skin infection, urticaria. Vascular disorders: Epistaxis. |
Patient Counseling Information
This drug may cause dizziness or drowsiness, if affected, do not drive or operate machinery.
|
MonitoringParameters
Monitor for signs and symptoms of behavioural changes.
|
Overdosage
Symptoms: Abdominal pain, somnolence, thirst, headache, vomiting, psychomotor hyperactivity. Management: Supportive treatment.
|
Drug Interactions
Decrease plasma concentration with CYP450 inducers (e.g. phenytoin, phenobarbital, rifampicin). Gemfibrozil may increase montelukast serum concentration.
|
Action
Description: Montelukast is a selective leukotriene receptor antagonist with a long duration of action. It inhibits cysteinyl leukotriene type-1 (CysLT1) receptor found in the human airway and on pro-inflammatory cells. The binding of CysLTs in leukotriene receptors are involved in the pathophysiology of asthma, including smooth muscle contraction, airway oedema and inflammation; CysLTs are released from the nasal mucosa after allergen exposure which is associated with symptoms of allergic rhinitis.
Onset: Asthma control: Within a day. Duration: >24 hours. Pharmacokinetics: Absorption: Rapidly absorbed. Bioavailability: 64% (conventional tab); 73% (chewable tab), 63% (with standard meal). Time to peak plasma concentration: 3-4 hours (conventional tab, fasting); 2 hours (4 mg chewable tab, fasting); 2-2.5 hours (5 mg chewable tab, fasting); 2.3±1 hour (granules, fasting), 6.4±2.9 hours (with high-fat meal). Distribution: Present in breastmilk. Volume of distribution: 8-11 L. Plasma protein binding: >99%. Metabolism: Extensively metabolised in the liver by CYP3A4, CYP2C8 and CYP2C9. Excretion: Mainly via faeces (86%); via urine (<0.2%). Elimination half-life: 2.7-5.5 hours. |
Chemical Structure
![]() Source: National Center for Biotechnology Information. PubChem Database. Montelukast, CID=5281040, https://pubchem.ncbi.nlm.nih.gov/compound/Montelukast (accessed on Jan. 23, 2020) |
Storage
Store below 30°C. Protect from light and moisture.
|
ATC Classification
R03DC03 - montelukast ; Belongs to the class of leukotriene receptor antagonists. Used in the systemic treatment of obstructive airway diseases.
|
References
Anon. Montelukast. Lexicomp Online. Hudson, Ohio. Wolters Kluwer Clinical Drug Information, Inc. https://online.lexi.com. Accessed 21/05/2019. Buckingham R (ed). Montelukast Sodium. Martindale: The Complete Drug Reference [online]. London. Pharmaceutical Press. https://www.medicinescomplete.com. Accessed 21/05/2019. McEvoy GK, Snow EK, Miller J et al (eds). Montelukast Sodium. AHFS Drug Information (AHFS DI) [online]. American Society of Health-System Pharmacists (ASHP). https://www.medicinescomplete.com. Accessed 30/09/2014. Montelukast Granule, Tablet (Ajanta Pharma Limited). DailyMed. Source: U.S. National Library of Medicine. https://dailymed.nlm.nih.gov/dailymed/. Accessed 21/05/2019. Montelukast Tablet (Amneal Pharmaceuticals LLC). DailyMed. Source: U.S. National Library of Medicine. https://dailymed.nlm.nih.gov/dailymed/. Accessed 21/05/2019. Singulair Tablets, Chewable Tablets, and Oral Granules. U.S. FDA. https://www.fda.gov/. Accessed 30/09/2014. Singulair Granule, Chewable Tablet, Film-Coated Tablet (Merck Sharp & Dohme Corp.). DailyMed. Source: U.S. National Library of Medicine. https://dailymed.nlm.nih.gov/dailymed/. Accessed 30/09/2014. Singulair Granule. U.S. FDA. https://www.fda.gov/. Accessed 30/09/2014.
|