Montelukast - Use | Dose | Side Effects

Montelukast is a drug from the group of leukotriene receptor antagonists. Cysteinyl leukotrienes are potent inflammatory mediators that are released in the airways smooth muscles. By blocking the effects of these substances, it prevents the development of bronchoconstriction and reduces the mucous secretion. Montelukast is used to treat asthma and to reduce incidence of asthmatic attacks.


Montelukast is not intended for the treatment of asthma attacks once they occur, but is only used to prevent/reduce the occurrence of asthma attacks.

It has an excellent safety profile and it does not cause significant and serious adverse effects.

It is associated with an increased incidence of eosinophilia (high number of eosinophils - a type of white blood cells), so if you notice a skin rash you should call your doctor.

Montelukast, pregnancy and breastfeeding

Studies on animals revealed no adverse effects on pregnancy and prenatal development, which is why AU TGA and FDA assigned this drug to group B. Consult with your doctor before you start taking this drug during pregnancy.

Montelukast should be used during breastfeeding only if necessary. Studies on rats have shown that this drug is excreted into milk, but there is no information whether this drug is excreted into human milk.


The recommended dose for the treatment of asthma and allergic rhinitis in patients older than 15 years is 10 mg once daily, in the evening, regardless of the meals.

Dose adjustment is not required for patients who have impaired renal or hepatic function, as well as in elderly patients.

For children aged 6-15 years, the recommended dose is 5 mg of Montelukast (in the form of chewable tablets) once a day, in the evening.

For children aged 2-5 years, the recommended dose is 4 mg of Montelukast (in the form of chewable tablets) once a day, in the evening.

For children aged 1-2 years, the recommended dose is 4 mg of Montelukast (in the form of granules - one sachet contains 4 mg of Montelukast) once a day.


Montelukast does not enter into major interactions with other drugs or food. This drug is metabolized by the enzyme CYP3A4 and should not be co-administered with inducers of this enzyme because these interactions can reduce concentration of Montelukast in the blood which will reduce its efficiency.

Therefore, caution is recommended during concomitant use of Montelukast with the following CYP3A4 inducers:

Adverse reactions

The most commonly reported adverse effects are headache, upper respiratory tract infection and abdominal pain.

Montelukast may also cause the following adverse reactions:

  • Eosinophilia (occurs very rarely)
  • Unusual susceptibility to bleed
  • Insomnia
  • Nightmares
  • Irritability
  • Restlessness
  • Anxiety
  • Depression
  • Hallucinations
  • Suicidal ideation
  • Paresthesia
  • Dizziness
  • Haematoma
  • Churg-Strauss syndrome
  • Vomiting
  • Nausea
  • Dyspepsia
  • Diarrhea
  • Dry mouth
  • Hepatitis
  • Muscle ache
  • Joint ache
  • Edema

Information on this website are provided for educational purposes only and are not intended for medical advice, diagnosis or treatment.

If you have any concerns or questions about your health, you should always consult with a physician or other health-care professional.