Ritalin 10mg (methylphenidate) is a stimulant medication commonly prescribed to treat Attention Deficit Hyperactivity Disorder (ADHD) and narcolepsy. Ritalin 10mg is available in the immediate-release (IR) formulation, which is usually taken two to three times a day, with doses spaced 4-6 hours apart. It typically begins working within 30 to 60 minutes of ingestion, and its effects last about 3-4 hours.