Adrenaline (also known as epinephrine) is a hormone and neurotransmitter released by the adrenal glands in response to sudden stress, excitement, or perceived danger. It acts almost instantaneously — accelerating the heart rate, increasing blood flow to muscles, dilating the airways, and sharpening the senses — preparing the body for rapid action. This is the core of the fight-or-flight response, and in genuine emergencies, it is a life-saving mechanism. Adrenaline is also released during exciting or novel experiences, which is why thrill-seeking activities can feel pleasurable.
For people living with anxiety, PTSD, or chronic stress, the adrenaline response can become easily triggered — activating even in the absence of real danger. This can manifest as racing heart, shallow breathing, heightened alertness, difficulty switching off, or a constant sense of being "on edge." Over time, a body frequently flooded with adrenaline can become exhausted and hypersensitive. Therapy — particularly somatic and trauma-informed approaches — can help people recognise, understand, and gently work with their adrenaline responses, rebuilding a sense of safety and regulation within the nervous system.
Cannon, W. B. (1932). The Wisdom of the Body. W. W. Norton & Company. (Foundational text on the fight-or-flight response and adrenaline.)
