Monkasta (Montelukast)

• Montelukast acts on the leukotriene pathway to control airway and nasal inflammation.
• Asthma: decreases the frequency and severity of bronchospasm episodes, improves overall lung function and reduces reliance on rescue inhalers.
• Exercise‑induced bronchoconstriction: helps prevent exercise‑triggered narrowing of the airways, allowing better tolerance of physical activity.
• Allergic rhinitis: relieves nasal congestion, sneezing, itching and rhinorrhea caused by seasonal or perennial allergens.
• Prevention of asthma exacerbations: supports long‑term control when used as part of a maintenance regimen.

• Montelukast selectively blocks the cysteinyl leukotriene receptor type 1 (CysLT1) on airway smooth‑muscle cells, epithelial cells and inflammatory cells. By antagonizing CysLT1, it prevents leukotriene‑mediated bronchoconstriction, vascular permeability, mucus secretion and eosinophilic inflammation, thereby reducing airway hyper‑responsiveness and nasal mucosal edema. The inhibition is competitive and long‑lasting, allowing once‑daily dosing and contributing to improved symptom control over time. This mechanism distinguishes it from beta‑agonists, which act directly on adrenergic receptors to induce bronchodilation.

Montelukast is generally well tolerated, but a range of adverse reactions have been reported.

Common Side Effects

• Headache
• Abdominal pain or dyspepsia
• Cough
• Fatigue
• Nausea
• Diarrhoea

Serious or Rare Side Effects

• Allergic reactions such as rash, urticaria or angioedema
• Neuropsychiatric events including agitation, depression or suicidal thoughts
• Hepatic enzyme elevation or hepatitis
• Anaphylaxis
• Stevens‑Johnson syndrome or toxic epidermal necrolysis
• Eosinophilic granulomatosis with polyangiitis (Churg‑Strauss syndrome)

• When prescribing Monkasta, clinicians should consider several safety aspects.
• Pregnancy: consult a healthcare provider; safety data are limited.
• Breastfeeding: use only if benefits outweigh potential risks.
• Pediatric use: dosage is age‑ and weight‑based; monitor for behavioral changes.
• Elderly: assess renal and hepatic function and review concomitant medicines.
• Drug interactions: review all current therapies, especially enzyme inducers or inhibitors.
• Store at ambient temperature: keep in the original pack, protect from moisture and direct sunlight.

Montelukast may interact with other medicines, requiring attention to avoid reduced efficacy or increased toxicity.

Major Interactions (Avoid)

• Phenobarbital: strong hepatic enzyme inducer that can lower montelukast exposure.
• Rifampin: potent CYP3A4 inducer, may diminish therapeutic effect.

Moderate Interactions (Monitor Closely)

• Warfarin: possible increase in INR; monitor coagulation parameters.
• Theophylline: additive central nervous system effects may occur.
• Beta‑agonists: combined bronchodilatory action may require dose adjustment.