Montelukast Indoco (Montelukast)

Montelukast acts on the leukotriene pathway to manage several respiratory conditions.

• Asthma: Provides maintenance therapy to reduce frequency and severity of asthma attacks.
• Allergic rhinitis: Relieves nasal congestion, sneezing and itching associated with seasonal allergies.
• Exercise‑induced bronchoconstriction: Prevents airway narrowing triggered by physical activity.

• Montelukast selectively blocks the cysteinyl leukotriene receptor CysLT1, preventing leukotrienes D4, E4 and F4 from binding. By inhibiting this receptor, the drug reduces bronchoconstriction, mucus secretion, vascular permeability and inflammatory cell recruitment in the airways, thereby improving respiratory function. The antagonism is dose‑dependent and results in sustained control of airway inflammation without affecting beta‑adrenergic pathways. This mechanism distinguishes Montelukast from bronchodilators and makes it suitable for long‑term prophylactic use.

Montelukast may cause a range of adverse reactions, most of which are mild and transient.

Common Side Effects

• Headache: mild to moderate pain often resolving without treatment.
• Upper respiratory infection: symptoms such as sore throat, nasal congestion or cough.
• Abdominal pain: discomfort in the stomach area, usually transient.
• Diarrhea: loose stools occurring occasionally.
• Cough: non‑productive cough without fever.
• Rash: mild skin redness or itching.

Serious or Rare Side Effects

• Allergic reactions: hives, swelling of face or throat, requiring immediate medical attention.
• Mood changes: depression, anxiety, or suicidal thoughts reported in rare cases.
• Hepatotoxicity: elevated liver enzymes indicating possible liver injury.
• Angioedema: rapid swelling of lips, tongue or airway.
• Stevens‑Johnson syndrome: severe skin blistering and mucosal involvement.

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

• Assess asthma control: confirm that the patient’s asthma is stable before initiating therapy.
• Monitor for neuropsychiatric events: observe for signs of depression, anxiety or suicidal ideation.
• Evaluate liver function: consider baseline hepatic tests in patients with existing liver disease.
• Use in children: follow age‑specific dosing guidelines and monitor growth parameters.
• Avoid use in patients with known hypersensitivity to Montelukast or any tablet excipients.
• Store at ambient temperature: keep below 25 °C, protect from moisture and store in original packaging.

Montelukast can interact with other medicines, affecting its efficacy or safety profile.

Major Interactions (Avoid)

• Phenobarbital: may reduce plasma concentrations of Montelukast, decreasing therapeutic effect.
• Rifampin: induces metabolism leading to lower Montelukast levels.

Moderate Interactions (Monitor Closely)

• Antidepressants (e.g., fluoxetine): potential additive neuropsychiatric effects.
• Beta‑agonists: concurrent use may increase risk of paradoxical bronchospasm.
• Warfarin: monitor INR as Montelukast may alter anticoagulant response.