BACK TO epinephrine

epinephrine vs. norepinephrine

epinephrine vs. norepinephrine: What’s the difference?

Epinephrine, also called adrenaline, is a hormone released in response to stress, such as anger or fear. It increases the heart rate and blood pressure, among other things. Norepinephrine, also called noradrenaline, is both a hormone and a neurotransmitter that constricts the blood vessels, raises the blood pressure, and dilates the bronchi. Commercially produced forms of both epinephrine and norepinephrine are used in medicine to treat specific conditions.

[ ep-uh-nef-rin, -reen ]
  1. a hormone secreted by the adrenal medulla upon stimulation by the central nervous system in response to stress, as anger or fear, and acting to increase heart rate, blood pressure, cardiac output, and carbohydrate metabolism.
  2. a commercial form of this substance, extracted from the adrenal glands of sheep and cattle, or synthesized: used chiefly as a heart stimulant, to constrict the blood vessels, and to relax the bronchi in asthma.
[ nawr-ep-uh-nef-rin, -reen ]
  1. a neurotransmitter, released by adrenergic nerve terminals in the autonomic and possibly the central nervous system, that has such effects as constricting blood vessels, raising blood pressure, and dilating bronchi.
  2. a commercial form of this substance used for emergency treatment of lowered blood pressure.

Compare More Commonly Confused Words