Which of the following is an example of a methylphenidate?

Ritalin is an example of methylphenidate, which is a central nervous system stimulant commonly used to treat attention deficit hyperactivity disorder (ADHD) and narcolepsy. Methylphenidate works by increasing the levels of certain neurotransmitters in the brain, specifically dopamine and norepinephrine, which helps improve attention, focus, and self-control in individuals with ADHD.

In contrast, Vyvanse and Adderall contain amphetamine salts and are thus classified as amphetamines, which while also used for ADHD, have a different chemical structure and mechanism of action compared to methylphenidate. Intuniv is not a stimulant; it is a medication that contains guanfacine, which is used to treat ADHD through a different mechanism, primarily affecting receptors in the brain to help improve attention and reduce hyperactivity without the stimulating effects of medications like Ritalin.