Zex-DMR Syrup is a combination pharmaceutical formulation containing Phenylephrine (5mg), Chlorpheniramine Maleate (2mg), and Dextromethorphan Hydrobromide (10mg) per dose. It is indicated for the symptomatic relief of cough and nasal congestion associated with upper respiratory tract infections such as the common cold, allergic rhinitis, and sinusitis. Phenylephrine acts as a selective alpha-1 adrenergic receptor agonist, providing effective vasoconstriction of nasal mucosa blood vessels, thereby reducing nasal congestion. Chlorpheniramine Maleate is a first-generation antihistamine that competitively inhibits H1 histamine receptors, alleviating allergic symptoms including rhinorrhea, sneezing, and itching. Dextromethorphan Hydrobromide serves as a centrally acting antitussive agent by suppressing the cough reflex in the medullary cough center without causing significant sedation or respiratory depression. Zex-DMR Syrup is generally well-tolerated when used as directed; however, caution is advised in patients with hypertension, glaucoma, or hyperthyroidism due to the sympathomimetic effects of Phenylephrine. It is contraindicated in individuals hypersensitive to any component of the formulation. Dosage should be strictly adhered to, and consultation with a healthcare professional is recommended before use, especially in pediatric, pregnant, or lactating patients. This combination therapy provides a multi-symptom approach to managing cough and nasal congestion effectively.