Comparative Pharmacology
Head-to-head clinical analysis: ADDERALL XR 20 versus DEXMETHYLPHENIDATE HYDROCHLORIDE.
Peer-Reviewed Evidence
Head-to-head clinical analysis: ADDERALL XR 20 versus DEXMETHYLPHENIDATE HYDROCHLORIDE.
ADDERALL XR 20 vs DEXMETHYLPHENIDATE HYDROCHLORIDE
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.
Dexmethylphenidate is a central nervous system (CNS) stimulant. Its mechanism of action in ADHD is not fully understood, but it is believed to block the reuptake of norepinephrine and dopamine into the presynaptic neuron, increasing their levels in the extraneuronal space.
20 mg orally once daily in the morning.
Initial: 5 mg orally twice daily (morning and noon) with or without food; titrate in increments of 5 mg weekly; maximum 20 mg twice daily (40 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.
2-4 hours (immediate-release); 4-5 hours (extended-release); clinical context: short half-life necessitates multiple daily dosing for immediate-release formulations
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 (78-97% as metabolites and unchanged drug, with approximately 50% as de-esterified metabolites and 30% as unchanged drug)
Category C
Category A/B
CNS Stimulant
CNS Stimulant