Short answers, pulled from the story.
Romanian chemist Lazăr Edeleanu synthesized the chemical compound phenylisopropylamine, now known as amphetamine, in Germany during 1887. Gordon Alles independently resynthesized the drug later in 1927 and reported its sympathomimetic properties.
Smith Kline and French introduced the first amphetamine pharmaceutical under the brand name Benzedrine by late 1933. Three years after this initial release, Benzedrine sulfate became available as a tablet form to treat narcolepsy, obesity, low blood pressure, and chronic pain.
The United States classified amphetamine as a schedule II controlled substance under the Controlled Substances Act in the early 1970s. The United Nations 1971 Convention on Psychotropic Substance also classified amphetamine as a schedule II controlled substance in all 183 state parties.
Dextroamphetamine produces roughly three to four times more stimulation of dopamine release compared to levoamphetamine due to higher binding affinity for the dopamine transporter. Levoamphetamine retains slightly stronger cardiovascular and peripheral effects despite lower dopaminergic potency.
Withdrawal symptoms occur in roughly 88% of chronic heavy users within 24 hours of their last dose and include anxiety, depressed mood, fatigue, increased appetite, sleeplessness, and lucid dreams. A marked crash phase typically occurs during the first week of discontinuation.