The brain is made up of nerve cells that send messages to each other by releasing chemicals called neurotransmitters. Common stimulants, such as amphetamines and methylphenidate, have chemical structures that are similar to certain key brain neurotransmitters including dopamine and norepinephrine. Stimulants boost the effects of these chemicals in the brain and body.
When doctors prescribe stimulants for a medical condition, they start with low doses and increase them slowly until they find the dose that works best. However, when taken in amounts or ways other than prescribed, like snorting or injecting, stimulants can increase the dopamine in the brain very quickly. This changes the normal communication between brain cells, producing a ‘high’ while also increasing the risk for dangerous side effects. Over time, this can lead to addiction, which is when you continue to use the drug despite negative consequences.
Learn more about how the brain works and what happens when a person miuses drugs.