Montelukast Teva (Montelukast Sodium)

Montelukast is a leukotriene‑blocking agent used in the management of several respiratory conditions.

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

• Montelukast selectively antagonizes the cysteinyl leukotriene receptor CysLT1, blocking the actions of leukotrienes D4, C4 and E4. By inhibiting these mediators, it reduces bronchial smooth‑muscle constriction, vascular permeability, and inflammatory cell recruitment that contribute to asthma and allergic airway disease.

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

Common Side Effects

• Headache: mild to moderate intensity.
• Upper respiratory tract infection: symptoms of cold or flu‑like illness.
• Abdominal pain: intermittent discomfort in the stomach area.
• Cough: non‑productive cough episodes.
• Diarrhoea: loose stools occurring occasionally.
• Rash: mild skin redness or itching.

Serious or Rare Side Effects

• Neuropsychiatric events: agitation, anxiety, depression or suicidal thoughts.
• Allergic reactions: hives, swelling of face or throat, difficulty breathing.
• Liver enzyme elevation: abnormal liver function test results.
• Severe skin reactions: Stevens‑Johnson syndrome or toxic epidermal necrolysis.

Before initiating therapy, consider the following safety measures.

• Pregnancy: discuss potential risks with a healthcare professional, as safety data are limited.
• Breastfeeding: evaluate benefits versus possible exposure to the infant.
• Hepatic impairment: use with caution in patients with liver disease.
• Concomitant psychiatric conditions: monitor for mood changes or suicidal ideation.
• Drug interactions: review all current medications for possible interactions.
• Store at ambient temperature: keep below 25 °C, retain in original packaging, protect from moisture and direct sunlight.

Montelukast may interact with other medicines, requiring attention to the interaction severity.

Major Interactions (Avoid)

• Phenobarbital or rifampin: may reduce montelukast plasma concentrations, decreasing efficacy.
• Strong CYP3A4 inhibitors (e.g., ketoconazole): could increase exposure, raising risk of adverse effects.

Moderate Interactions (Monitor Closely)

• Warfarin: occasional reports of altered INR; monitor coagulation parameters.
• Beta‑agonists: additive bronchodilator effect may enhance symptom control.
• Other leukotriene modifiers: combined use may increase side‑effect burden without added benefit.