Buy Ritalin Online, a popular brand name for Methylphenidate, is commonly used to treat children with Attention Deficit Hyperactivity Disorder (ADHD) by stimulating the children's central nervous system (CNS). The effect of Ritalin works by blocking the highly active dopamine transporters, such as cocaine and other stimulants. These transporters are responsible for removing excess dopamine. In people with ADHD, it is believed that dopamine runs out very quickly. This makes it difficult for them to be involved in what is happening.