Lecmon 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 idiopathic urticaria. Levocetirizine, a third-generation non-sedating antihistamine, selectively inhibits peripheral H1 histamine receptors, thereby reducing symptoms like sneezing, nasal congestion, itching, and rhinorrhea. Montelukast, a leukotriene receptor antagonist, blocks the cysteinyl leukotriene receptor, which plays a key role in the inflammatory process associated with asthma and allergic rhinitis. The synergistic action of these two agents provides comprehensive relief from allergic symptoms by targeting different pathways of the allergic response. Lecmon 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 disturbances, though these are generally mild and transient. Caution is advised in patients with hepatic impairment and those with a history of neuropsychiatric events. Lecmon 5mg/10mg Tablet should be used under medical supervision, with dosage adjustments based on clinical response and patient tolerance. It is not intended for acute asthma attacks and should be stored in a cool, dry place away from direct sunlight.