Dextroamphetamine

Dextroamphetamine (INN: dexamfetamine) is a potent central nervous system (CNS) stimulant and enantiomer of amphetamine that is used in the treatment of attention deficit hyperactivity disorder (ADHD) and narcolepsy. It is also used illicitly to enhance cognitive and athletic performance, and recreationally as an aphrodisiac and euphoriant. Dextroamphetamine is generally regarded as the prototypical stimulant.

The amphetamine molecule exists as two enantiomers, levoamphetamine and dextroamphetamine. Dextroamphetamine is the dextrorotatory, or 'right-handed', enantiomer and exhibits more pronounced effects on the central nervous system than levoamphetamine. Pharmaceutical dextroamphetamine sulfate is available as both a brand name and generic drug in a variety of dosage forms. Dextroamphetamine is sometimes prescribed as the inactive prodrug lisdexamfetamine.

Side effects of dextroamphetamine at therapeutic doses include elevated mood, decreased appetite, dry mouth, excessive grinding of the teeth, headache, increased heart rate, increased wakefulness or insomnia, anxiety, and irritability, among others. At excessively high doses, psychosis (i.e., hallucinations, delusions), addiction, and rapid muscle breakdown may occur. However, for individuals with pre-existing psychotic disorders, there may be a risk of psychosis even at therapeutic doses.

Dextroamphetamine, like other amphetamines, elicits its stimulating effects via several distinct actions: it inhibits or reverses the transporter proteins for the monoamine neurotransmitters (namely the serotonin, norepinephrine and dopamine transporters) either via trace amine-associated receptor 1 (TAAR1) or in a TAAR1 independent fashion when there are high cytosolic concentrations of the monoamine neurotransmitters and it releases these neurotransmitters from synaptic vesicles via vesicular monoamine transporter 2 (VMAT2). It also shares many chemical and pharmacological properties with human trace amines, particularly phenethylamine and N-methylphenethylamine, the latter being an isomer of amphetamine produced within the human body. It is available as a generic medication. In 2022, mixed amphetamine salts (Adderall) was the 14th most commonly prescribed medication in the United States, with more than 34 million prescriptions.