Comparative Pharmacology
Head-to-head clinical analysis: ADDERALL XR 20 versus XELSTRYM.
Head-to-head clinical analysis: ADDERALL XR 20 versus XELSTRYM.
ADDERALL XR 20 vs XELSTRYM
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.
XELSTRYM (dextroamphetamine transdermal system) is a sympathomimetic amine that increases synaptic concentrations of dopamine and norepinephrine by inhibiting their reuptake and promoting their release from presynaptic terminals.
20 mg orally once daily in the morning.
Initial: one 9-mg patch applied to the hip once daily; titrate weekly in 4.5-mg increments to desired effect; maximum dose: 18 mg/day.
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.
Mean terminal elimination half-life of dexmethylphenidate is approximately 2-3 hours in children and adolescents, with no significant accumulation at steady state; clinical effects correlate with plasma concentrations.
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 (90% as unchanged drug and metabolites, primarily dehydrodexmethylphenidate and inactive metabolites); minor biliary/fecal elimination (<5%)
Category C
Category C
CNS Stimulant
CNS Stimulant