Ritalin (methylphenidate) is a central nervous system (CNS) stimulant that is frequently prescribed to treat Attention Deficit Hyperactivity Disorder (ADHD) and narcolepsy. The 10 mg dose is a typical immediate-release preparation used to treat symptoms of inattention, impulsivity, and hyperactivity. Ritalin has methylphenidate hydrochloride, a stimulant that acts on neurotransmitters in the brain, specifically dopamine and norepinephrine.