H-Rex 25 Tablet contains Hydroxyzine 25 mg, an antihistamine with anxiolytic, sedative, and antiemetic properties. It is primarily indicated for the symptomatic relief of anxiety and tension associated with psychoneurosis and as an adjunct in organic disease states in which anxiety is manifested. Hydroxyzine acts by antagonizing central and peripheral histamine H1 receptors, thereby reducing allergic symptoms such as pruritus and urticaria. Additionally, it exhibits anticholinergic and sedative effects, making it useful in managing nausea, vomiting, and as a premedication before anesthesia to induce sedation and reduce anxiety. The recommended dosage varies depending on the indication, patient age, and clinical response, with careful consideration in elderly patients and those with hepatic or renal impairment. Common side effects include drowsiness, dry mouth, and headache, while rare adverse reactions may involve QT interval prolongation and hypersensitivity reactions. H-Rex 25 Tablet should be used with caution in patients with a history of cardiac arrhythmias or prolonged QT syndrome. It is contraindicated in individuals with hypersensitivity to Hydroxyzine or related compounds. Patients should avoid alcohol and other CNS depressants during treatment. Consultation with a healthcare professional is advised before initiating therapy to ensure appropriate use and monitoring.