Comparative Pharmacology
Head-to-head clinical analysis: ADDERALL XR 15 versus CONCERTA.
Peer-Reviewed Evidence
Head-to-head clinical analysis: ADDERALL XR 15 versus CONCERTA.
ADDERALL XR 15 vs CONCERTA
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.
Methylphenidate is a central nervous system (CNS) stimulant. It blocks the reuptake of norepinephrine and dopamine into presynaptic neurons, increasing their levels in the synaptic cleft. It also acts as a dopamine agonist by stimulating the release of dopamine from storage sites.
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.
18-72 mg orally once daily in the morning, starting at 18-36 mg/day and titrating in 18 mg increments weekly; maximum 72 mg/day.
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.
Terminal elimination half-life of methylphenidate from CONCERTA is approximately 3.5 hours (range 2.5-5.5 hours) in adults; in children, mean half-life is 3-4 hours. The extended-release formulation provides a prolonged clinical effect due to the OROS delivery system, not prolonged half-life.
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%.
Primarily renal (77%-87% as unchanged drug and metabolites); metabolic elimination accounts for 13%-23%, with minor biliary excretion (<2%).
Category C
Category C
CNS Stimulant
CNS Stimulant