phen·​yl·​eph·​rine | \ ˌfe-nᵊl-ˈe-ˌfrēn How to pronounce phenylephrine (audio) , -frən \

Definition of phenylephrine

: a sympathomimetic agent C9H13NO2 that is used in the form of its hydrochloride as a vasoconstrictor, a mydriatic, a nasal decongestant, and by injection to raise the blood pressure

Examples of phenylephrine in a Sentence

Recent Examples on the Web Anything containing phenylephrine, which is the active ingredient in many popular over-the-counter nasal decongestants, may be particularly harmful to those with cardiovascular issues. Zee Krstic, Good Housekeeping, 11 Jan. 2021 Each pod has acetaminophen to relieve pain and reduce fevers, dextromethorphan HBr to quiet coughs and phenylephrine HCl to clear nasal passages. Good Housekeeping Editors, Good Housekeeping, 16 Oct. 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'phenylephrine.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of phenylephrine

circa 1947, in the meaning defined above

History and Etymology for phenylephrine

phenyl + epinephrine

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Time Traveler for phenylephrine

Time Traveler

The first known use of phenylephrine was circa 1947

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Dictionary Entries Near phenylephrine

phenyl cyanide


phenyl ether

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Statistics for phenylephrine

Cite this Entry

“Phenylephrine.” Dictionary, Merriam-Webster, Accessed 15 Aug. 2022.

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More Definitions for phenylephrine


phen·​yl·​eph·​rine | \ ˌfen-ᵊl-ˈef-ˌrēn, -rən How to pronounce phenylephrine (audio) \

Medical Definition of phenylephrine

: a sympathomimetic agent with vasoconstrictive properties that is used in the form of its hydrochloride C9H13NO2·HCl especially as a nasal decongestant and mydriatic and to raise blood pressure

Note: Trademarks for preparations containing phenylephrine include Actifed and Neo-Synephrine.


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