Lesys-M Tablet contains Levocetirizine 5 mg and Montelukast 10 mg, combining an antihistamine and a leukotriene receptor antagonist to provide comprehensive relief from allergic conditions. Levocetirizine, a third-generation non-sedating antihistamine, selectively inhibits peripheral H1 receptors, effectively reducing symptoms such as sneezing, nasal congestion, rhinorrhea, and itching associated with allergic rhinitis and chronic urticaria. Montelukast acts by blocking leukotriene D4 receptors in the lungs and bronchial tubes, thereby preventing bronchoconstriction and inflammation commonly observed in asthma and allergic rhinitis. The synergistic action of these agents makes Lesys-M Tablet particularly beneficial for patients experiencing both upper respiratory allergic symptoms and lower airway inflammation. It is indicated for the treatment of seasonal and perennial allergic rhinitis, chronic idiopathic urticaria, and as adjunctive therapy in mild to moderate asthma. Lesys-M is generally well tolerated; common adverse effects may include headache, fatigue, and gastrointestinal disturbances. It should be used with caution in patients with hepatic impairment and is contraindicated in individuals with known hypersensitivity to either component. Dosage and administration should be as prescribed by a healthcare professional, with regular monitoring to assess therapeutic response and safety.