Zadonase Tablet is a combination medication containing Montelukast 10mg and Fexofenadine 120mg, formulated for the management of allergic conditions such as allergic rhinitis and chronic urticaria. Montelukast, a leukotriene receptor antagonist, works by blocking leukotriene D4 in the lungs and bronchial tubes, thereby reducing inflammation, bronchoconstriction, and mucus production. Fexofenadine, a second-generation antihistamine, selectively inhibits peripheral H1 receptors, alleviating symptoms like sneezing, nasal congestion, runny nose, and itching without causing significant sedation. The synergistic action of these two agents provides comprehensive relief from both early and late-phase allergic responses. Zadonase is indicated for patients requiring effective control of seasonal and perennial allergic rhinitis, as well as chronic idiopathic urticaria. It is generally well tolerated, with a low incidence of adverse effects such as headache, dizziness, or gastrointestinal discomfort. Caution is advised in patients with hepatic or renal impairment, and it should be used under medical supervision in children and pregnant or lactating women. Zadonase Tablet offers a convenient once-daily dosing regimen, enhancing patient compliance and improving quality of life in individuals suffering from allergic disorders.