Comparative Pharmacology
Head-to-head clinical analysis: ADDERALL XR 20 versus DEXEDRINE SPANSULE.
Peer-Reviewed Evidence
Head-to-head clinical analysis: ADDERALL XR 20 versus DEXEDRINE SPANSULE.
ADDERALL XR 20 vs DEXEDRINE SPANSULE
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Adderall XR 20 is a combination of amphetamine enantiomers (dextroamphetamine and levoamphetamine). It increases synaptic levels of dopamine and norepinephrine by inhibiting their reuptake and promoting their release from presynaptic terminals.
Dextroamphetamine is a central nervous system (CNS) stimulant that increases synaptic concentrations of norepinephrine and dopamine by blocking their reuptake and promoting release from presynaptic terminals.
20 mg orally once daily in the morning.
5-60 mg orally once daily in the morning, using extended-release capsules.
None Documented
None Documented
Approximately 10-13 hours for d-amphetamine and 13-15 hours for l-amphetamine in adults; in children, 9-11 hours. The extended-release formulation provides a prolonged therapeutic effect masking shorter elimination.
Terminal elimination half-life is 6-8 hours in adults, 10-13 hours in children, and prolonged in alkaline urine (up to 16-20 hours) due to enhanced tubular reabsorption. In hepatic impairment, half-life may extend to 12-15 hours. Steady-state is reached within 2-3 days.
Approximately 90% of an oral dose is excreted renally, with 30% as unchanged amphetamine and the remainder as metabolites (including hippuric acid, benzoic acid, and hydroxylated derivatives). Fecal/biliary excretion accounts for <10%.
Renal excretion of unchanged drug (approximately 30-40% unchanged) and hepatic metabolism to inactive metabolites (primarily hippuric acid, benzoic acid, and hydroxylated derivatives). About 90% of a dose is excreted in urine within 48 hours, with 10-15% as unchanged dextroamphetamine; minor biliary/fecal elimination (<5% total).
Category C
Category C
CNS Stimulant
CNS Stimulant