Comparative Pharmacology
Head-to-head clinical analysis: DEXEDRINE SPANSULE versus QUILLICHEW ER.
Peer-Reviewed Evidence
Head-to-head clinical analysis: DEXEDRINE SPANSULE versus QUILLICHEW ER.
DEXEDRINE SPANSULE vs QUILLICHEW ER
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
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.
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.
5-60 mg orally once daily in the morning, using extended-release capsules.
Initial 20 mg orally once daily, titrate by 10 mg weekly to maximum 60 mg/day (methylphenidate component).
None Documented
None Documented
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.
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.
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).
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