More commonly known as Ritalin or Methylin, methylphenidate is a mild central nervous system stimulant prescribed primarily to treat attention deficit disorders and narcolepsy. Its mechanism is not completely understood, but methylphenidate presumably activates the brain stem arousal system and cortex to produce its stimulant effect. The drug can have a stabilizing effect for children with Attention-Deficit Hyperactivity Disorder (ADHD), helping to control behavioral problems such as distractibility, short attention span, hyperactivity, emotional ability, and impulsiveness.
Although it helps the minority of children who genuinely suffer from ADHD, concern has been growing about the dramatic increase in Ritalin use. From 1990 to 1996, the number of prescriptions increased by 500%, 400% for amphetamines also used to treat ADHD. This has led the Drug Enforcement Administration to conclude that, "These drugs have been over-promoted, over-marketed and over-sold, resulting in profits of some $450 million annually." Even so, there have been shortages because Ritalin is strictly regulated as a Schedule II Controlled Substance and its production restricted by the government.
Adding to the shortage is its diversion to the illegal drug market. When the tablets are crushed and inhaled, or put into solution and injected, the drug produces a cocaine-like stimulant effect. Ironically, it's become a popular choice for drug abuse amongst adolescents. One 1994 survey of students indicated that more high school seniors in the USA abuse Ritalin than are prescribed Ritalin legitimately.