Comparative Pharmacology
Head-to-head clinical analysis: ADDERALL XR 25 versus BENZEDRINE.
Peer-Reviewed Evidence
Head-to-head clinical analysis: ADDERALL XR 25 versus BENZEDRINE.
ADDERALL XR 25 vs BENZEDRINE
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Adderall XR is a combination of dextroamphetamine and amphetamine, which are non-catecholamine sympathomimetic amines that promote release of catecholamines (primarily dopamine and norepinephrine) from presynaptic nerve terminals and inhibit their reuptake, resulting in increased synaptic concentrations. This leads to CNS stimulation.
Benzedrine (racemic amphetamine) releases dopamine and norepinephrine from presynaptic neurons, blocks their reuptake, and inhibits monoamine oxidase, increasing synaptic monoamine levels.
20-60 mg orally once daily in the morning; starting dose 20 mg, titrate weekly by 10-20 mg based on response and tolerability.
Oral: 5-10 mg once or twice daily, maximum 40 mg/day. Intramuscular: 5-10 mg every 30-60 minutes as needed, maximum 40 mg/day.
None Documented
None Documented
Dextroamphetamine: 10-13 hours; levoamphetamine: 11-14 hours. Effective half-life supports once-daily dosing with extended duration.
Terminal elimination half-life: 4-6 hours in adults (range 4-8 hours). Clinically, duration of action correlates with half-life, but tolerance may develop with repeated dosing.
Renal: approximately 90% (30-40% unchanged, remainder as metabolites); fecal: minimal (<2%) via biliary elimination.
Renal (30-40% unchanged, pH-dependent), with minor biliary/fecal elimination. At acidic urine pH, elimination half-life is shortened; at alkaline pH, reabsorption increases.
Category C
Category C
CNS Stimulant
CNS Stimulant