Montelukast

 

1. Generic Name & Brand Names

• Generic Name: Montelukast Sodium

• Brand Names:

  • Singulair® (Global)

  • Montek® (India)

  • Lukair® (EU)

  • Generic equivalents (e.g., "Montelukast")

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2. Dosage Forms

• Oral:

  • Chewable Tablets (4 mg, 5 mg)

  • Film-Coated Tablets (10 mg)

  • Oral Granules (4 mg/packet)

• No injectable/topical forms

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3. Drug Class

• Leukotriene Receptor Antagonist (LTRA)

• Blocks cysteinyl leukotriene (CysLT₁) receptors

• Anti-inflammatory, bronchoprotective

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4. FDA-Approved Uses

• Asthma:

  • Prophylaxis & chronic treatment (≥1 year)

  • Prevents bronchoconstriction, reduces inflammation

• Allergic Rhinitis (AR):

  • Seasonal/perennial allergies (≥2 years)

• Exercise-Induced Bronchoconstriction (EIB):

  • Prevention (≥6 years)

• Off-label: Chronic urticaria, aspirin-exacerbated respiratory disease (AERD)

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5. Side Effects

Common (≥1%)	Serious (Discontinue Immediately)
Headache (18%)	Neuropsychiatric Effects: • Aggression, depression • Hallucinations, suicidal ideation
Abdominal pain	Eosinophilia (rare vasculitis)
Dizziness	Severe hypersensitivity
Fever (children)	Liver injury (elevated LFTs)
Rash

⚠️ Black Box Warning (FDA): Neuropsychiatric events (agitation, suicide risk).

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6. Critical Warnings

• Neuropsychiatric Risks:

  • Monitor for behavior changes, nightmares (especially in children/teens).

• Contraindications:

  • Hypersensitivity to montelukast

  • Phenylketonuria (PKU) - aspartame in chewables

• Pregnancy/Lactation:

  • Category B (limited data) - use only if benefits > risks.

• Not for Acute Asthma Attacks:

  • No bronchodilator effect - keep rescue inhaler (e.g., albuterol).

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7. How to Take

Age Group	Dose & Form	Timing
Adults ≥15 yrs	10 mg tablet	Once daily, evening
Children 6-14 yrs	5 mg chewable tablet	Once daily, evening
Children 2-5 yrs	4 mg chewable/granules	Once daily, evening
Infants 6-23 mo	4 mg oral granules	Once daily, evening

• Key Instructions:

  • Take on empty stomach (1 hr before/2 hrs after food) or consistently with food.

  • Granules: Mix with applesauce/ice cream (not liquids).

  • For EIB: Take ≥2 hours before exercise (no additional dose within 24 hrs).

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8. Missed Dose

• Skip if >12 hours late

• Never double dose

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9. Drug Interactions

Medication	Risk
Phenobarbital	↓ Montelukast levels
Rifampicin	↓ Efficacy (CYP2C8/3A4 inducer)
Gemfibrozil	↑ Montelukast levels (monitor)

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10. Storage

• Tablets/Granules: 15-30°C (59-86°F); keep granules in foil until use.

• Protect from light/moisture.

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Clinical Safety Alerts

⚠️ Neuropsychiatric Monitoring:

• FDA Mandate (2020): Boxed warning for suicide risk. Report aggression, anxiety, or sleep disturbances immediately.
  ⚠️ Asthma Control:

• Not a substitute for inhaled corticosteroids (ICS). Often used as add-on therapy.
  ⚠️ Pediatric Granules:

• Avoid mixing with liquids - use soft foods only to ensure full dose delivery.

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Efficacy Insights

✅ Asthma:

• Reduces exacerbations by 31% vs. placebo (NEJM).

• Add-on to ICS improves symptom control (GINA guidelines).
  ✅ Allergic Rhinitis:

• Superior to placebo for nasal congestion relief (Ann Allergy Asthma Immunol).
  ❌ Limitations:

• Less effective than ICS for moderate-severe asthma.

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Montelukast vs. Inhaled Corticosteroids

Parameter	Montelukast	Fluticasone (ICS)
Mechanism	LTRA	Anti-inflammatory
Onset	1 day (peak 3 mos)	2-8 days
Delivery	Oral	Inhalation
Adverse Effects	Neuropsychiatric	Oral thrush, dysphonia
Pediatric Use	>6 months	>4 years

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Patient Counseling Points

1. "Take at bedtime" – maximizes nighttime asthma control.

2. "Not for sudden attacks" – always carry rescue inhaler.

3. "Report mood changes" – nightmares/aggression require immediate review.

4. "Don't stop abruptly" – no rebound effect but asthma may worsen.

💡 Pro Tip: Combine with antihistamines (e.g., loratadine) for additive allergy relief.

Prescription Status: Requires prescription in most countries (OTC in some Middle Eastern nations).