Comparative Pharmacology
Head-to-head clinical analysis: ADDERALL 12 5 versus ADDERALL XR 20.
Peer-Reviewed Evidence
Head-to-head clinical analysis: ADDERALL 12 5 versus ADDERALL XR 20.
ADDERALL 12.5 vs ADDERALL XR 20
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Adderall 12.5 is a combination of dextroamphetamine and amphetamine. It increases the levels of dopamine and norepinephrine in the central nervous system by inhibiting their reuptake and promoting their release from presynaptic neurons.
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.
5-60 mg orally once or twice daily; immediate-release: initial 5 mg once or twice daily, increase by 5 mg weekly; extended-release: initial 20 mg once daily in the morning, increase by 10 mg weekly.
20 mg orally once daily in the morning.
None Documented
None Documented
The terminal elimination half-life of d-amphetamine is approximately 10–13 hours in adults (range 9–14 h) and 6–8 hours in children. Clinical context: Typically allows twice-daily dosing; extended-release formulations provide 8–12 hours of effect.
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.
Approximately 30% of the dose is excreted unchanged in urine; the remainder is metabolized primarily via deamination and oxidation. Renal elimination of unchanged amphetamine is pH-dependent: acidic urine increases elimination, alkaline urine decreases it. Fecal excretion accounts for <5%.
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%.
Category C
Category C
CNS Stimulant
CNS Stimulant