What is the function of adrenaline hormone?

Adrenaline (also called epinephrine) is a hormone secreted by the adrenal glands located above the kidneys. It functions as the body's "emergency hormone" or "fight-or-flight" hormone. When you face a stressful or dangerous situation, adrenaline is rapidly released into the bloodstream, causing immediate physiological changes: increased heart rate and blood pressure, faster breathing, dilation of pupils, increased blood flow to muscles, enhanced alertness, and quick release of glucose for instant energy. These changes prepare the body to either confront the threat or escape from it, which is why you might feel your heart racing during frightening or exciting moments.