Comparative Pharmacology
Head-to-head clinical analysis: ADDERALL 10 versus ADDERALL XR 20.
Peer-Reviewed Evidence
Head-to-head clinical analysis: ADDERALL 10 versus ADDERALL XR 20.
ADDERALL 10 vs ADDERALL XR 20
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Adderall 10 contains a mixture of amphetamine salts (dextroamphetamine and levoamphetamine). Amphetamines are non-catecholamine sympathomimetic amines that promote the release of dopamine and norepinephrine from presynaptic neurons, inhibit their reuptake, and inhibit monoamine oxidase activity, thereby increasing extracellular levels of these neurotransmitters in the central nervous system.
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.
10 mg orally once daily in the morning, with or without food; may increase by 5-10 mg weekly based on tolerability and response; usual effective dose 10-40 mg/day divided into 2-3 doses; maximum 60 mg/day.
20 mg orally once daily in the morning.
None Documented
None Documented
Terminal elimination half-life: dextroamphetamine 9-11 hours, levoamphetamine 11-14 hours (Adderall is a mixed salt). In adults, mean half-life ~10 hours; in children, slightly shorter (6-8 hours). Clinical context: steady-state reached in 2-3 days; dosing interval typically 4-6 hours for immediate-release.
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.
Renal: 70-80% (30-40% as unchanged amphetamine; remainder as deaminated and hydroxylated metabolites). Fecal: minimal (<5%). Biliary: negligible. Urinary pH affects excretion: acidic urine increases elimination, alkaline urine decreases.
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