epinephrine

noun

epi·​neph·​rine ˌe-pə-ˈne-frən How to pronounce epinephrine (audio)
variants or less commonly epinephrin
: a crystalline sympathomimetic hormone C9H13NO3 that is the principal blood-pressure raising hormone secreted by the medulla of the adrenal glands, is prepared from adrenal extracts or made synthetically, and is used medicinally especially to stimulate the heart during cardiac arrest and to treat life-threatening allergic reactions

called also adrenaline

Examples of epinephrine in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
While people, particularly those with allergies, can take precautions such as carrying an epinephrine pen and keeping an eye out for the ants, there’s not much else that can be done. Don Sweeney, Miami Herald, 10 June 2025 Other treatments for peanut allergy include: Avoiding foods that contain peanuts Receiving antibody injections (Xolair) to build up tolerance Preparing for a severe allergic reaction by carrying an emergency epinephrine autoinjector (EpiPen), or epinephrine nasal spray (Neffy). Tom Gavin, EverydayHealth.com, 24 Apr. 2025 Patients are typically administered epinephrine, an adrenaline treatment. Cara Lynn Shultz, People.com, 24 Apr. 2025 The complaint says the hospital failed to administer epinephrine promptly and lacked pediatric intubation equipment. Real-Time News Team, Miami Herald, 11 Apr. 2025 See All Example Sentences for epinephrine

Word History

Etymology

International Scientific Vocabulary epi- + Greek nephros kidney — more at nephritis

First Known Use

1899, in the meaning defined above

Time Traveler
The first known use of epinephrine was in 1899

Browse Nearby Words

Cite this Entry

“Epinephrine.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/epinephrine. Accessed 22 Jun. 2025.

Kids Definition

epinephrine

noun
ep·​i·​neph·​rine
ˌep-ə-ˈnef-rən
: a hormone of the adrenal gland acting especially on smooth muscle, causing narrowing of blood vessels, and raising blood pressure

called also adrenaline

Medical Definition

epinephrine

noun
epi·​neph·​rine
variants also epinephrin
: a colorless crystalline sympathomimetic hormone C9H13NO3 that is the principal blood-pressure-raising hormone secreted by the adrenal medulla, is prepared from adrenal extracts or made synthetically, and is used medicinally especially to stimulate the heart during cardiac arrest and to treat life-threatening allergic reactions

called also adrenaline

More from Merriam-Webster on epinephrine

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