Levonair 5mg/10mg Tablet is a combination medication containing Levocetirizine 5mg and Montelukast 10mg, indicated for the management of allergic conditions such as allergic rhinitis and chronic urticaria. Levocetirizine, a third-generation non-sedating antihistamine, selectively antagonizes peripheral H1 receptors, thereby reducing symptoms like sneezing, nasal congestion, itching, and rhinorrhea. Montelukast, a leukotriene receptor antagonist, inhibits the cysteinyl leukotriene D4 receptor, which plays a key role in airway inflammation and bronchoconstriction, making it effective in preventing asthma symptoms and improving respiratory function. The combined action of these agents provides comprehensive relief from allergic manifestations by targeting different inflammatory pathways. Levonair is typically administered once daily, with or without food, and is well tolerated in adults and adolescents. Common adverse effects may include headache, fatigue, and gastrointestinal discomfort, though serious side effects are rare. Caution is advised in patients with hepatic impairment or a history of neuropsychiatric events. Levonair should be used under medical supervision, with dosage adjustments as necessary based on clinical response and patient tolerance. This combination therapy offers an effective option for patients requiring dual symptomatic control of allergic and asthmatic conditions.