Comparative Pharmacology
Head-to-head clinical analysis: ADDERALL XR 15 versus ADDERALL XR 20.
Peer-Reviewed Evidence
Head-to-head clinical analysis: ADDERALL XR 15 versus ADDERALL XR 20.
ADDERALL XR 15 vs ADDERALL XR 20
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
ADDERALL XR contains a mixture of amphetamine salts, including dextroamphetamine and levoamphetamine. The mechanism of action involves increasing synaptic levels of dopamine and norepinephrine by inhibiting their reuptake and enhancing their release from presynaptic terminals, leading to CNS stimulation.
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.
Oral, 20-60 mg once daily in the morning; initial dose 20 mg once daily, titrated by 10-20 mg weekly based on tolerability and efficacy.
20 mg orally once daily in the morning.
None Documented
None Documented
The terminal elimination half-life of amphetamine in adults is approximately 10-13 hours; in children, it is slightly shorter (6-8 hours). For the l-amphetamine isomer, the half-life is 9-11 hours. The extended-release formulation provides a prolonged duration of effect due to a biphasic release profile.
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.
Renal: approximately 90% of a dose is excreted in urine, with about 30% as unchanged amphetamine and the remainder as metabolites including deaminated and oxidized products; fecal excretion accounts for less than 10%.
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%.
Category C
Category C
CNS Stimulant
CNS Stimulant