Ritalin. or Methylphenidate hydrochloride—the generic for Ritalin, is a stimulant used to treat attention deficit hyperactivity disorder (ADHD) and to manage symptoms of narcolepsy. It affects the parts of the brain and central nervous system that control hyperactivity and impulses. Ritalin is one of the trade names for the drug known as methylphenidate. Other brand names can include Concerta, Methylin, and Metadate.