Comparative Pharmacology
Head-to-head clinical analysis: ADDERALL XR 20 versus QUILLICHEW ER.
Peer-Reviewed Evidence
Head-to-head clinical analysis: ADDERALL XR 20 versus QUILLICHEW ER.
ADDERALL XR 20 vs QUILLICHEW ER
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.
Quillichew ER contains methylphenidate, a central nervous system (CNS) stimulant. The mechanism of action in ADHD is not fully understood, but it is thought to block the reuptake of norepinephrine and dopamine into the presynaptic neuron, increasing their availability in the extraneuronal space.
20 mg orally once daily in the morning.
Initial 20 mg orally once daily, titrate by 10 mg weekly to maximum 60 mg/day (methylphenidate component).
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.
The terminal elimination half-life of methylphenidate is approximately 3-4 hours in children and 3.5-5 hours in adults. For QuilliChew ER, the extended-release formulation provides a prolonged absorption phase, with an effective duration of action of up to 12 hours.
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%.
QuilliChew ER (methylphenidate extended-release chewable tablet) is primarily eliminated via renal excretion as metabolites (60-80%) and unchanged drug (approx. 10%). Hepatic metabolism accounts for the remainder. Fecal elimination is minimal.
Category C
Category C
CNS Stimulant
CNS Stimulant