The drugs are normally prescribed to treat attention deficit hyperactivity disorder (ADHD), but healthy students use them to get a leg up in school, by improving focus, concentration and memory.
Adrenaline, or epinephrine, is a hormone that dilates an individual's air passages and increases his heart rate when he is faced with a stressful situation. The hormone is secreted from the adrenal glands to help ensure survival under dangerous situations.
Adrenaline is a chemical (actually a hormone) produced by the two adrenal glands, which are located on top of the kidneys (ad-renal, on-kidney). These glands secrete adrenaline directly into the blood stream when people are exposed to something that they see as potentially dangerous.