Montair; Singulair (brand availability varies by market)
Dosage form
Tablet
Strength
10 mg tablets for adults; chewable tablets and granules use different strengths.
Prescription classification
Prescription only (Schedule H / verified)
Approved routes of administration
Oral
Applies to
IN; product status and availability may vary by jurisdiction
Approved indications
Montelukast is a leukotriene receptor antagonist used as a regular controller medicine for selected patients with asthma and, in some cases, allergic rhinitis. It is not a rescue inhaler and will not stop a sudden asthma attack.
Contraindications (do not use if…)
Do not take montelukast if you have had a serious allergic reaction to it or any ingredient in the product. Check formulation-specific age restrictions.
Important precautions
Montelukast carries a warning about serious mood, behaviour, and sleep changes. Tell your doctor about any mental health history and watch for new agitation, anxiety, depression, unusual dreams, or suicidal thoughts. Do not stop other asthma medicines unless your doctor says so.
Common side effects
Common effects may include headache, stomach pain, cough, or upper respiratory symptoms — though experiences vary between people.
Serious side effects — seek urgent medical care
Get urgent help for suicidal thoughts, major mood or behaviour changes, a severe allergic reaction, or worsening breathing.
Important interactions
Tell your doctor about all medicines, especially rifampicin and some seizure medicines, which can affect montelukast blood levels.
Allergy considerations
Avoid montelukast if you have had a serious reaction to it or any ingredient in the product.
Pregnancy and lactation
Pregnancy safety
Use with caution — see notes
Notes
Your doctor should review montelukast during pregnancy, balancing asthma control needs against any available alternatives.
Information
Lactation safety
Use with caution — see notes
Notes
Discuss montelukast with your doctor while breastfeeding, especially if your baby is premature or has medical needs.
Children and older adults
Use the formulation and strength appropriate for the patient's age. Granules and chewable tablets come with specific instructions.
Storage
Store in original packaging at room temperature, away from moisture and children.
Missed dose
Follow the product leaflet — usually take the next scheduled dose and do not double up. Do not take extra medicine for an asthma attack.
Overdose
Seek medical advice if you suspect an overdose, especially if restlessness, headache, vomiting, stomach pain, or unusual sleepiness occurs.
If you suspect an overdose or accidental poisoning:
contact your local emergency services or the nearest hospital emergency department immediately. Do not wait for symptoms.
Montair; Singulair (brand availability varies by market)
Dosage form
Tablet
Strength
10 mg tablets for adults; chewable tablets and granules use different strengths.
Prescription classification
Prescription only (Schedule H / verified)
Approved routes of administration
Oral
Applies to
IN; product status and availability may vary by jurisdiction
Approved indications
Montelukast is a leukotriene receptor antagonist used as a regular controller medicine for selected patients with asthma and, in some cases, allergic rhinitis. It is not a rescue inhaler and will not stop a sudden asthma attack.
Contraindications (do not use if…)
Do not take montelukast if you have had a serious allergic reaction to it or any ingredient in the product. Check formulation-specific age restrictions.
Important precautions
Montelukast carries a warning about serious mood, behaviour, and sleep changes. Tell your doctor about any mental health history and watch for new agitation, anxiety, depression, unusual dreams, or suicidal thoughts. Do not stop other asthma medicines unless your doctor says so.
Common side effects
Common effects may include headache, stomach pain, cough, or upper respiratory symptoms — though experiences vary between people.
Serious side effects — seek urgent medical care
Get urgent help for suicidal thoughts, major mood or behaviour changes, a severe allergic reaction, or worsening breathing.
Important interactions
Tell your doctor about all medicines, especially rifampicin and some seizure medicines, which can affect montelukast blood levels.
Allergy considerations
Avoid montelukast if you have had a serious reaction to it or any ingredient in the product.
Pregnancy and lactation
Pregnancy safety
Use with caution — see notes
Notes
Your doctor should review montelukast during pregnancy, balancing asthma control needs against any available alternatives.
Information
Lactation safety
Use with caution — see notes
Notes
Discuss montelukast with your doctor while breastfeeding, especially if your baby is premature or has medical needs.
Children and older adults
Use the formulation and strength appropriate for the patient's age. Granules and chewable tablets come with specific instructions.
Storage
Store in original packaging at room temperature, away from moisture and children.
Missed dose
Follow the product leaflet — usually take the next scheduled dose and do not double up. Do not take extra medicine for an asthma attack.
Overdose
Seek medical advice if you suspect an overdose, especially if restlessness, headache, vomiting, stomach pain, or unusual sleepiness occurs.
If you suspect an overdose or accidental poisoning:
contact your local emergency services or the nearest hospital emergency department immediately. Do not wait for symptoms.
