Ritalin is a prescription medication used to treat attention deficit hyperactivity disorder (ADHD) and narcolepsy. It contains the active ingredient methylphenidate, which is a central nervous system (CNS) stimulant that increases the levels of dopamine and norepinephrine in the brain, leading to improved focus, attention, and alertness. Ritalin is available in immediate-release and extended-release formulations. The immediate-release tablets are typically taken 2 to 3 times a day, while the extended-release capsules are taken once daily in the morning. The dose may be adjusted based on individual response and tolerance.