Generic Medicine Info
Indications and Dosage
Chronic asthma
Adult: Prophylaxis and maintenance therapy: 20 mg bid. Recommended therapeutic indications may vary between countries (refer to local or specific product guidelines).
Child: 5-11 years 10 mg bid; ≥12 years Same as adult dose. Recommended therapeutic indications may vary between countries (refer to local or specific product guidelines).
Hepatic Impairment
Should be taken on an empty stomach.
Hepatic impairment including hepatic cirrhosis.
Special Precautions
Not indicated for use in acute asthma attacks (including status asthmaticus). Children and elderly. Pregnancy and lactation.
Adverse Reactions
Significant: Hepatotoxicity (e.g. hyperbilirubinaemia, hepatitis); neuropsychiatric events (e.g. insomnia, depression); infections predominantly affecting the respiratory tract (mostly to >55 years of age). Rarely, systemic eosinophilia (sometimes manifesting with clinical features of vasculitis consistent with eosinophilic granulomatosis with polyangiitis [formerly known as Churg-Strauss syndrome]).
Blood and lymphatic system disorders: Agranulocytosis.
Gastrointestinal disorders: Nausea, vomiting, abdominal pain, diarrhoea, dyspepsia.
General disorders and administration site conditions: Fever, oedema, malaise.
Immune system disorders: Hypersensitivity reactions (e.g. urticaria, angioedema, pruritus, rashes with or without blistering).
Investigations: Increased serum ALT.
Musculoskeletal and connective tissue disorders: Myalgia, arthralgia, back pain.
Nervous system disorders: Headache, dizziness.
Vascular disorders: Bleeding, bruising.
Potentially Fatal: Hepatic failure leading to liver transplantation.
Monitoring Parameters
Monitor LFTs periodically. Closely monitor for signs and symptoms of hepatic injury and neuropsychiatric symptoms or behavioural changes.
Symptoms: Rash and stomach upset. Management: Supportive treatment. Empty the stomach by inducing emesis or performing gastric lavage. May administer activated charcoal to prevent further absorption of unrecovered drug.
Drug Interactions
May enhance the anticoagulant activity of warfarin resulting in prolonged prothrombin time. May reduce serum concentration with theophylline, terfenadine, and erythromycin. Increased serum concentration with fluconazole and high doses of aspirin.
Food Interaction
Decreased rate and extent of absorption with food.
Mechanism of Action: Zafirlukast, an antiasthmatic agent, is a competitive and selective leukotriene-receptor antagonist (LTRA) of leukotriene D4 and E4 (LTD4 and LTE4), components of slow-reacting substance of anaphylaxis (SRSA). The production, stimulation, and receptor occupation of cysteinyl leukotriene have been correlated with the pathophysiology of asthma including smooth muscle constriction, airway oedema, and altered cellular activity related with the inflammatory process which contribute to the signs and symptoms of asthma.
Absorption: Rapidly absorbed from the gastrointestinal tract. Food reduces the rate and extent of absorption. Time to peak plasma concentration: Approx 3 hours.
Distribution: Enters breast milk. Plasma protein binding: Approx 99%, mainly to albumin.
Metabolism: Extensively metabolised in the liver mainly by CYP2C9 isoenzyme into hydroxylated metabolites.
Excretion: Mainly via faeces (approx 90%, as unchanged drug and metabolites); urine (approx 10%, as metabolites). Elimination half-life: Approx 10 hours (range 8-16 hours).
Chemical Structure

Chemical Structure Image

Source: National Center for Biotechnology Information. PubChem Compound Summary for CID 5717, Zafirlukast. Accessed Feb. 27, 2024.

Store between 20-25°C. Protect from light and moisture.
MIMS Class
Antiasthmatic & COPD Preparations
ATC Classification
R03DC01 - zafirlukast ; Belongs to the class of leukotriene receptor antagonists. Used in the systemic treatment of obstructive airway diseases.
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Buckingham R (ed). Zafirlukast. Martindale: The Complete Drug Reference [online]. London. Pharmaceutical Press. Accessed 10/01/2024.

Zafirlukast Tablet, Film Coated (Aurobindo Pharma Limited). DailyMed. Source: U.S. National Library of Medicine. Accessed 10/01/2024.

Zafirlukast. Gold Standard Drug Database in ClinicalKey [online]. Elsevier Inc. Accessed 21/02/2024.

Disclaimer: This information is independently developed by MIMS based on Zafirlukast from various references and is provided for your reference only. Therapeutic uses, prescribing information and product availability may vary between countries. Please refer to MIMS Product Monographs for specific and locally approved prescribing information. Although great effort has been made to ensure content accuracy, MIMS shall not be held responsible or liable for any claims or damages arising from the use or misuse of the information contained herein, its contents or omissions, or otherwise. Copyright © 2024 MIMS. All rights reserved. Powered by
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