The fight-or-flight hormone released by the adrenal glands is called .

Epinephrine, also called adrenaline, is released by the adrenal glands during the fight-or-flight response. It helps prepare the body for quick action by increasing heart rate and making more energy available. Cortisol is also involved in stress, but epinephrine is the hormone commonly identified as the fight-or-flight hormone.

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