Histafree-M Tablet is a combination medication containing Montelukast 10 mg and Fexofenadine 120 mg, indicated for the management of allergic conditions such as allergic rhinitis and chronic urticaria. Montelukast, a leukotriene receptor antagonist, works by blocking leukotriene D4 at the cysteinyl leukotriene receptor, thereby reducing inflammation, bronchoconstriction, and mucus production associated with allergic responses. Fexofenadine, a second-generation antihistamine, selectively inhibits peripheral H1 receptors, effectively alleviating symptoms like sneezing, nasal congestion, itching, and hives without causing significant sedation. The synergistic action of these two agents provides comprehensive relief from both immediate and delayed allergic reactions. Histafree-M is generally well tolerated; common adverse effects may include headache, dizziness, and gastrointestinal discomfort. It is contraindicated in patients with known hypersensitivity to either component. Caution is advised in individuals with hepatic or renal impairment, and concurrent use with other central nervous system depressants should be monitored. This combination therapy offers a convenient once-daily dosing regimen, improving patient compliance in the treatment of allergic disorders. As with all medications, use under medical supervision is recommended to ensure safety and efficacy.