Explanation

Adrenaline (also called epinephrine) is a hormone. If you have a serious allergic reaction, you may be given an injection of adrenaline to treat it.

The adrenaline then travels through your bloodstream and stops your immune system from releasing histamine, which helps swelling in your skin go away. Adrenaline also shields your lungs, making it easier for you to breathe, and increases your heart rate to get more glucose and oxygen to your cells!