You're probably not familiar with the medication known as methylphenidate, but you almost certainly know what Ritalin is. Methylphenidate is the generic name for the prescription drug Ritalin, which is known on the street as Vitamin R, Rids, and R-ball. Ritalin is prescribed legally for the treatment of attention-deficit hyperactivity disorder, or ADHD, as well as for the sleeping disorder narcolepsy. When used without a prescription, Ritalin is taken to stimulate the body, and has effects that are quite similar to cocaine in many ways. Ritalin is very popular on college campuses due to its appetite suppressing, fatigue fighting, and concentration enhancing effects. Ritalin is usually taken recreationally by crushing the drug and snorting the power. Once in the body, Ritalin acts to arouse the brain stem and cortex. The drug also stimulates the release of the feel-good hormone dopamine. Abuse of Ritalin may lead to physical addiction for this reason. A dose of Ritalin lasts three to four hours, while an extended-release tablet will work for up to eight. If you take too much Ritalin, you may experience a rapid heartbeat, blurred vision, and in more serious cases, fainting, or even a seizure. Over time, the insoluble fibers in Ritalin tablets may block small blood vessels, which can lead to potential cardiovascular complications and lung damage. Ritalin is illegal without a prescription, so one should be very careful if using it recreationally.