Vyvanse is a prescription medication that is primarily used to treat attention deficit hyperactivity disorder (ADHD) and binge eating disorder. It contains the active ingredient lisdexamfetamine, which is a central nervous system stimulant that works by affecting certain chemicals in the brain that contribute to hyperactivity and impulse control. When purchasing Vyvanse online, it is crucial to ensure that you are sourcing it from verified and trusted pharmacies to guarantee the authenticity and safety of the medication.