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Singulair, known for its anti-inflammatory properties, is a prescription medication that contains the active ingredient montelukast sodium.

Last Modified: 08 May 2024

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What is Singulair? 

Singulair, known for its anti-inflammatory properties, is a prescription medication that contains the active ingredient montelukast sodium. Montelukast is a leukotriene receptor antagonist that helps to block substances in the body called leukotrienes, an inflammatory mediator, which cause asthma and allergic rhinitis symptoms. 

The structure of Singulair involves montelukast as the active compound, usually formulated as a film-coated tablet. It is synthesized through a series of chemical reactions that yield the final active pharmaceutical ingredient, which is then processed into tablet form. 

Global Name

Generic name: Montelukast
Brand name: Singulair, Montair, and others


What is Singulair used for? 

Singulair is prescribed to manage and prevent symptoms of asthma and to relieve the symptoms of seasonal and perennial allergic rhinitis (hay fever). It is not used to relieve an acute asthma attack. 

Conditions treated by Singulair include: 

  • Asthma (both exercise-induced and chronic) 
  • Allergic Rhinitis (seasonal and year-round allergies) 

How do you use Singulair? 

Availability: Singulair is available in tablet form, chewable tablets, and granules for oral suspension.

Dosage information: 

  • Children aged 2-5 years: 4 mg chewable tablet or one packet of 4 mg oral granules once daily in the evening. 
  • Children aged 6-14 years: 5 mg chewable tablet once daily in the evening. 
  • Adults and adolescents aged 15 years and older: 10 mg tablet once daily in the evening. 


  • Children: Suitable for children 2 years and older with specific pediatric dosages. 
  • Adults: Suitable with standard adult dosage. 
  • Elderlies: Suitable; no dosage adjustment necessary. 

Who can’t take Singulair? 

  • Children under 2 years 
  • Adults with hypersensitivity to montelukast 
  • Elderlies with no specific contraindications but should be used with caution 
  • Pregnancy: Use only if clearly needed and the benefits outweigh the risks 
  • Lactation: Caution is advised; consult with healthcare professional 

Allergies: Avoid if allergic to montelukast or any other excipients in the formulation. 

Warnings and precautions: Singulair should be taken in the evening for asthma management, and at the same time each day for allergic rhinitis. 

Interactions and contraindications: 

  • Caution with phenobarbital or rifampin as they may decrease montelukast levels. 
  • No contraindications, but potential interactions with other drugs should be discussed with a healthcare provider. 

Side Effects

Common side effects include abdominal pain, headache, and thirst. Serious side effects are rare but include behavior changes. 

Pharmacist Tips

  • Storage information: Store at room temperature away from light and moisture. 
  • Handling instructions: Do not remove the tablets from the original packaging until you are ready to use them. 


Where is Singulair available in Hong Kong?

Singulair is a prescription medication that can be prescribed by healthcare providers.


Is Singulair for purchase over-the-counter?

No, Singulair is a prescription medication and requires a doctor's authorization.

Can Singulair be used with other allergy medications?

Yes, Singulair can be used in conjunction with other allergy medications but always consult with a healthcare provider before combining treatments.

Should Singulair be taken with food?

Singulair can be taken with or without food, but consistency in timing of the dose is recommended, preferably in the evening for asthma.

How long does Singulair take to work?

Some effects may be noticed within a day, but it may take several weeks for full benefits.

Can I use Singulair during acute asthmatic attacks? 

No, Singular is not effective for acute exacerbation of asthma. First-line medications of acute asthma attacks include inhaled beta-agonists such as salbutamol/albuterol, anti-cholinergic ipratropium, sympathomimetic epinephrine and inhaled corticosteroids (beclomethasone, budesonide, fluticasone). 

This website provides content related to drug use and medicine for informational purposes only. It is not a substitute for professional medical advice, diagnosis, or treatment. Do not use the information on this website to diagnose or treat a health problem or disease without consulting a qualified healthcare provider. The website's owners and contributors are not liable for any repercussions, adverse effects, or consequences resulting from the use of any medication or information provided herein.

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