Drug abuse destroys the brain. The drug inundate the brain with the neurotransmitter, dopamine. Dopamine regulates emotions, pleasure, movement, and pleasure. A drug abuser when "high"is overwhelmed by dopamine, and has euphoric episodes, as the drug leaves the system so does the feeling, resulting in an opposite feeling (misery or depression). This results in the person craving for more drugs, thus the vicious cycle continues, altering the brain activity, convincing the brain to prioritize drugs over everything else.
