Modulair (Montelukast)

Montelukast is a leukotriene receptor antagonist used to manage conditions involving airway inflammation and bronchoconstriction.

• Asthma: improves control of symptoms and reduces frequency of exacerbations in patients with persistent asthma.
• Exercise‑induced bronchoconstriction: prevents narrowing of airways triggered by physical activity, reducing the need for rescue inhalers.
• Allergic rhinitis: alleviates nasal congestion, sneezing and itching associated with seasonal allergic rhinitis.

• Montelukast selectively blocks the cysteinyl leukotriene receptor CysLT1 on airway smooth‑muscle cells, mast cells and eosinophils. By antagonizing the actions of leukotrienes C4, D4 and E4, it prevents receptor‑mediated bronchoconstriction, vascular permeability and mucus secretion, thereby reducing airway inflammation and hyper‑responsiveness. The inhibition of these mediators also contributes to decreased recruitment of inflammatory cells and less edema in the respiratory mucosa.

Montelukast is generally well tolerated, but some patients may experience adverse reactions.

Common Side Effects

• Headache: mild to moderate intensity, may be transient.
• Upper respiratory tract infection: sore throat, runny nose, or mild fever.
• Abdominal pain: stomach discomfort, sometimes accompanied by nausea.

Serious or Rare Side Effects

• Allergic reactions: rash, itching, swelling, or anaphylaxis requiring immediate medical attention.
• Mood changes: depression, agitation, or suicidal thoughts; monitor mental health closely.
• Stevens‑Johnson syndrome: severe skin blistering and mucosal involvement, a medical emergency.

Before prescribing Montelukast, clinicians should consider several precautionary measures to ensure safe use.

• Assess asthma control: confirm that the patient’s asthma is not uncontrolled before initiating therapy.
• Monitor mental health: watch for new or worsening depression, anxiety, or suicidal ideation.
• Review liver function: consider baseline hepatic enzymes in patients with known liver disease.
• Avoid use in acute asthma attacks: Montelukast is not a rescue medication for sudden bronchospasm.
• Caution in pregnancy: limited data; prescribe only if the potential benefit outweighs risks.
• Store at ambient temperature: keep below 25°C in the original packaging, protect from moisture.

Montelukast may interact with other medicines, altering its effectiveness or increasing the risk of adverse effects.

Major Interactions (Avoid)

• Phenobarbital, carbamazepine, phenytoin: enzyme inducers that can reduce montelukast plasma concentrations.
• Ritonavir or other strong CYP3A4 inhibitors: may increase montelukast levels, potentially enhancing side effects.

Moderate Interactions (Monitor Closely)

• Warfarin: occasional reports of altered INR; monitor coagulation parameters.
• Antidepressants (SSRIs, SNRIs): monitor for additive mood changes.
• Theophylline: may increase the risk of theophylline toxicity; observe serum levels.