Amphetamine treats ADHD—and can also hijack reward
Lazăr Edeleanu isolated the chemical in 1887; medicine adopted it in the late 1920s as Benzedrine. Today it is first-line for ADHD and narcolepsy, while recreational megadoses risk addiction and psychosis that therapeutic regimens rarely produce.
Amphetamine is a CNS stimulant prescribed for attention deficit hyperactivity disorder and narcolepsy, and as lisdexamfetamine for binge eating disorder. It also has a history as a decongestant and antidepressant, plus nonmedical use as a performance, cognitive, aphrodisiac, or euphoriant drug. Unauthorized possession is tightly controlled because recreational health risks are substantial. Chemically it is a phenethylamine with two enantiomers, levoamphetamine and dextroamphetamine; modern products include racemic mixes, Adderall, dextroamphetamine, and the prodrug lisdexamfetamine. It boosts monoamine signaling, especially norepinephrine and dopamine.
At therapeutic doses people may feel more awake and focused, with faster reaction time, less fatigue and appetite, higher heart rate, and more muscle strength—alongside mood and libido shifts. Larger recreational amounts can worsen cognition, trigger rapid muscle breakdown, and, at very high levels, psychosis. Addiction is a serious risk with heavy nonmedical use yet unlikely from long-term medical dosing in the usual range. For ADHD, models point to impaired dopamine and norepinephrine pathways; stimulants including amphetamine improve symptoms in about 80 percent of users. Multi-year randomized trials support continuous stimulant therapy as effective and relatively safe for core ADHD symptoms and broader functional outcomes.
Lisdexamfetamine, doses of 50–70 mg in adult trials, is as of July 2024 the only USFDA- and TGA-approved drug for moderate-to-severe binge eating disorder, reducing binge days in reviews that include longer open-label follow-up. Type 1 narcolepsy, by contrast, reflects loss of roughly 70,000 orexin neurons and low cerebrospinal orexin—an amphetamine indication aimed at daytime sleepiness. Animal high-dose exposure can damage dopamine systems, yet MRI reviews in treated ADHD suggest therapeutic amphetamine can lessen structural and functional brain abnormalities. The same molecule, in other words, is either a calibrated neurotransmitter nudge or a chaotic overdose—dose and intent decide which.
Source: Amphetamine
