Montelucaste Ciclum (Montelukast)

Montelukast acts on the leukotriene pathway to reduce airway inflammation and bronchoconstriction.

• Asthma: improves symptom control and reduces the frequency of exacerbations.
• Allergic rhinitis: alleviates nasal congestion, sneezing and itching caused by seasonal allergens.
• Exercise‑induced bronchoconstriction: prevents airway narrowing that occurs during or after physical activity.

• Montelukast selectively blocks the cysteinyl leukotriene receptor CysLT1, preventing leukotrienes from binding and triggering bronchoconstriction, mucus secretion, and inflammatory cell recruitment. By inhibiting this pathway, it reduces airway edema and hyper‑responsiveness, contributing to better respiratory function in asthma and related allergic conditions.

Montelukast is generally well tolerated, but adverse reactions can occur.

Common Side Effects

• Headache: mild to moderate discomfort.
• Abdominal pain: intermittent stomach discomfort.
• Cough: transient irritation of the throat.
• Nausea: occasional feeling of queasiness.
• Dizziness: brief episodes of light‑headedness.
• Sore throat: mild irritation of the pharynx.

Serious or Rare Side Effects

• Allergic reactions: rash, angioedema, or anaphylaxis.
• Neuropsychiatric events: depression, anxiety, or suicidal thoughts.
• Hepatic enzyme elevation: abnormal liver function tests.
• Severe skin reactions: Stevens‑Johnson syndrome or toxic epidermal necrolysis.
• Hematologic changes: neutropenia or eosinophilia.

Montelukast should be used with attention to specific safety considerations.

• Pregnancy: Category B – use only if clearly needed.
• Breastfeeding: considered compatible, but monitor infant for adverse effects.
• Neuropsychiatric monitoring: observe for mood changes or suicidal ideation.
• Hepatic impairment: dose adjustment may be required in severe liver disease.
• Hypersensitivity: discontinue if signs of allergic reaction appear.
• Store at room temperature: keep in the original container, protect from moisture and direct sunlight.

Montelukast may interact with other medicines that affect its metabolism or share similar therapeutic actions.

Major Interactions (Avoid)

• Concurrent use with another leukotriene antagonist (e.g., zafirlukast) – risk of additive toxicity.
• Known hypersensitivity to montelukast or any tablet excipients – may precipitate severe allergic response.

Moderate Interactions (Monitor Closely)

• Strong CYP3A4 inducers (e.g., rifampin) – may reduce montelukast exposure.
• Strong CYP3A4 inhibitors (e.g., ketoconazole, ritonavir) – may increase drug levels.
• Phenobarbital or carbamazepine – may lower plasma concentrations.
• Warfarin – monitor INR as montelukast can occasionally affect anticoagulation.