Final answer:
Phenylephrine is a sympathomimetic drug used for decongestion, pupil dilation, and increasing blood pressure. It is metabolized by COMT and MAO. It is commonly paired with other drugs in over-the-counter medications for sinus congestion and cough.
Step-by-step explanation:
Phenylephrine is a common sympathomimetic drug used as a decongestant. It can also dilate pupils and increase blood pressure. As an α₁-adrenergic agonist, phenylephrine binds to adrenergic receptors, stimulating a response. It is often paired with other pharmaceuticals in over-the-counter drugs for sinus congestion and cough.
Phenylephrine is metabolized by Catechol-O-Methyl-Transferase (COMT) and Mono-Amine Oxidase (MAO) in the liver, resulting in the formation of metabolites that are excreted.