Levoamphetamine

Levoamphetamine, or L-amphetamine, is the levorotatory enantiomer of amphetamine, a synthetic phenethylamine and central nervous system stimulant. It exists alongside dextroamphetamine (D-amphetamine) as one of the two enantiomers of amphetamine. In chemical terms, levoamphetamine is the (R)-enantiomer, while dextroamphetamine is the (S)-enantiomer.

Pharmacology and effects

Levoamphetamine acts as a monoamine releasing agent, increasing synaptic dopamine and norepinephrine. It has weaker central nervous system stimulant effects than dextroamphetamine, but tends to produce more pronounced peripheral sympathomimetic activity, such as elevated heart rate and blood pressure. When present in racemic amphetamine preparations, levoamphetamine contributes to the overall stimulant profile, with its enantiomeric ratio influencing potency and side-effect patterns.

Medical uses and formulations

Levoamphetamine is rarely used as a standalone medication in modern practice. It occurs as a component of mixed amphetamine salt formulations and is part of racemic amphetamine preparations that historically sold under brands such as Benzedrine. In contemporary ADHD and related therapies, dextroamphetamine predominates or medications provide a mixture of enantiomers; pure levoamphetamine is not commonly prescribed by itself.

Safety and regulation

Like other amphetamines, levoamphetamine is a controlled substance with potential for abuse, dependence, and adverse cardiovascular or psychiatric effects. Regulatory controls and availability vary by country. As with all stimulant medications, careful medical supervision is advised to manage risks and optimize therapeutic outcomes.

Chemistry and nomenclature

The compound has the formula C9H13N. In stereochemical terms, it is distinguished from dextroamphetamine by its optical rotation, occupying the role of the (R)-enantiomer in contrast to the (S)-dextro form. It is one of two enantiomers that constitute racemic amphetamine.