Which of the following ADHD medications is not a stimulant?

A. Adderall (amphetamine/dextroamphetamine) is a stimulant that increases dopamine and norepinephrine levels in the brain, improving focus and impulse control in individuals with ADHD. It is a Schedule II controlled substance due to its potential for abuse and dependence. B. Strattera (atomoxetine) is a non-stimulant medication used for ADHD. It is a selective norepinephrine reuptake inhibitor (NRI) that helps with attention and impulse control but has a lower risk of abuse compared to stimulant medications. Unlike stimulants, it may take several weeks to show full effects. C. Vyvanse (lisdexamfetamine) is a stimulant that is a prodrug of dextroamphetamine, meaning it must be metabolized in the body before becoming active. This mechanism provides a longer, smoother effect with a lower potential for abuse compared to immediate-release stimulants. D. Ritalin (methylphenidate) is a stimulant that increases dopamine and norepinephrine activity in the brain, improving focus and impulse control. It is commonly used in both children and adults with ADHD and has short-acting, intermediate, and long-acting formulations.