API

Montelukast sodium, Levocetirizine dihydrochloride

Drug classification

Dosage form

Tablet

API strength per dosage

Montelukast sodium 10mg and Levocetrizine…

Dose

Adults and adolescents (≥15 years): 1 tablet once daily in the evening. Children 6–14 years: 1 tablet once daily in the evening if appropriate formulation strength. Use with caution in hepatic impairment; not recommended in severe renal impairment. Dose adjustment not required in mild-to-moderate renal or hepatic impairment.

Mechanism of action

Montelukast selectively antagonizes cysteinyl leukotriene receptor type 1 (CysLT1), inhibiting leukotriene D4-mediated bronchoconstriction and inflammation. Levocetirizine competitively inhibits peripheral histamine H1 receptors, blocking histamine-induced vasodilation, increased vascular permeability, and sensory nerve stimulation.

Indications

Allergic rhinitis, seasonal allergic rhinitis, perennial allergic rhinitis, chronic idiopathic urticaria, prophylaxis and treatment of asthma.

Side effects

Drowsiness, headache, dry mouth, fatigue, abdominal pain, diarrhea, dizziness, upper respiratory tract infection, agitation, insomnia, depression, suicidal thoughts, hypersensitivity reactions, anaphylaxis.

Pregnancy category

Category B

Precautions

Hypersensitivity to components, severe renal impairment, history of neuropsychiatric disorders, concurrent alcohol or CNS depressant use, pregnancy and lactation, phenylketonuria (if aspartame present), elderly patients, children under 6 years (unless specified), potential drowsiness, avoid abrupt discontinuation in asthma, monitor for behavioral changes.

Contraindications

Hypersensitivity to montelukast, levocetirizine, cetirizine, or any tablet component, severe renal impairment (creatinine clearance <10 mL/min), end-stage renal disease, hereditary galactose intolerance, lactase deficiency, glucose-galactose malabsorption.