Phenylephrine

Excerpt

Phenylephrine primarily acts as an alpha-1 adrenergic receptor agonist and exhibits minimal to no beta-adrenergic activity. Consequently, the medication is an optimal choice for raising mean arterial pressure by inducing vasoconstriction in both veins and arteries and enhancing cardiac preload without exerting significant effects on cardiac myocytes. The US Food and Drug Administration (FDA) has approved intravenous phenylephrine hydrochloride to elevate blood pressure in adults experiencing clinically significant hypotension, primarily attributed to vasodilation, in situations such as septic shock or anesthesia. Phenylephrine HCL is also an over-the-counter (OTC) medication in ophthalmic formulations to facilitate mydriasis and vasoconstriction of conjunctival blood vessels. Furthermore, this medication is administered intranasally to treat uncomplicated nasal congestion and is an OTC additive to topical hemorrhoid medications.