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What is adrenaline?

Medicine & HealthLesson on requestFree to read

Quick answer

Adrenaline (also called epinephrine) is a hormone released by the adrenal glands that powers your 'fight or flight' response. In moments of stress or danger it floods the body, sharpening focus and preparing you for fast action. It is released by the adrenal glands when the brain senses stress or danger.

Key things to understand

  1. It is released by the adrenal glands when the brain senses stress or danger.
  2. It speeds the heart, widens the airways, and pushes blood and energy to the muscles.
  3. It sharpens alertness and dulls pain for a short burst — the 'adrenaline rush'.
  4. It works fast and fades fast, unlike the slower-acting stress hormone cortisol.
  5. Injected adrenaline (an EpiPen) can reverse a severe allergic reaction.

People also ask

What does an adrenaline rush feel like?
A racing heart, heightened alertness, rapid breathing, and a burst of energy — your body priming itself to act fast.
What is the difference between adrenaline and cortisol?
Adrenaline acts within seconds for an immediate burst; cortisol acts more slowly to sustain the body's response to longer stress.
How does an EpiPen use adrenaline?
It injects a dose of adrenaline that quickly opens the airways and tightens blood vessels, counteracting a life-threatening allergic reaction.