The combination of four amphetamine salts, including levoamphetamine and dextroamphetamine, improves focus, attention span, and control over impulsive behaviour by raising dopamine and norepinephrine levels in the brain. Adderall 30mg is a high-dose prescription drug that is mainly used to treat Attention Deficit Hyperactivity Disorder (ADHD) and, in some cases, narcolepsy.