A particular class of medicine that raises the amounts of specific brain chemicals, boosting alertness, attention, energy, and physical activity. Additionally raising blood pressure, heart rate, and breathing rate are other effects of CNS stimulants. They are used to treat narcolepsy, depression, and attention deficit hyperactivity disorder, which affects a person’s ability to pay attention, regulate their actions and remain calm or silent (a sleep disorder). Also known as a stimulant of the central nervous system.