Adderall 20mg is a medication commonly used to treat attention deficit hyperactivity disorder (ADHD) and narcolepsy. It contains a combination of amphetamine and dextroamphetamine, which are central nervous system stimulants that affect chemicals in the brain and nerves that contribute to hyperactivity and impulse control. For individuals with ADHD, Adderall helps increase their ability to focus, pay attention, and control behavior.