Ritalin Ritalin (Methylphenidate) is a mild CNS stimulant. In medicine, Ritalin's primary use is treatment of Attention Deficit /Hyperactive Disorder (ADHD). The mode of action in humans is not completely understood, but Ritalin presumably activates the arousal system of the brain stem and the cortex to produce its stimulant effect. Recently, the frequency of diagnosis for ADHD has increased dramatically. More children and an increasing number of adults are being diagnosed with ADHD. According to the Drug Enforcement Agency (DEA) (Bailey 1995), prescriptions for Ritalin have increased more than 600% in the past five years. Rit