CNS stimulants (CNS stands for central nervous system) are medicines that stimulate the brain, speeding up both mental and physical processes.
They increase energy, improve attention and alertness, and elevate blood pressure, heart rate and respiratory rate. They decrease the need for sleep, reduce appetite, improve confidence and concentration, and lessen inhibitions.
Experts aren’t exactly sure how CNS stimulants work, although they suspect they increase levels of one or more neurotransmitters in the brain, such as dopamine, norepinephrine, or serotonin. They may also have other effects, depending on the actual drug. For example, phentermine possibly indirectly increases leptin levels – leptin is a substance that tells us we feel full.
