Amphetamine (alpha-methylphenathylamine) is powerful central nervous system (CNS) stimulant used in the treatment of attention deficit hyperactivity disorder (ADHD) and narcolepsy. It is also used as a cognitive and performance enhancer and recreationally as an aphrodisiac and a euphoric stimulant. In therapeutic doses, amphetamine improves cognitive abilities, reduces reaction time, fights fatigue and increases muscle strength. Much larger doses can trigger rapid muscle breakdown and impair cognitive function. Extremely high doses can result in psychosis. Examples of prescribed amphetamines are Adderall and Dexedrine.