Comparative Pharmacology
Head-to-head clinical analysis: ADDERALL XR 20 versus METHYLPHENIDATE.
Peer-Reviewed Evidence
Head-to-head clinical analysis: ADDERALL XR 20 versus METHYLPHENIDATE.
ADDERALL XR 20 vs METHYLPHENIDATE
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
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.
Methylphenidate is a central nervous system (CNS) stimulant that blocks the reuptake of dopamine and norepinephrine into presynaptic neurons, increasing their extracellular concentrations. It also acts as a dopamine and norepinephrine releaser. The therapeutic effect in ADHD is thought to be due to increased dopaminergic signaling in the prefrontal cortex.
20 mg orally once daily in the morning.
Oral: Initial 5 mg twice daily (before breakfast and lunch), increase by 5-10 mg weekly; usual dose 20-30 mg/day in divided doses; maximum 60 mg/day. Extended-release: 18-36 mg once daily; maximum 72 mg/day.
None Documented
None Documented
Clinical Note
moderateDexmethylphenidate + Haloperidol
"The metabolism of Haloperidol can be decreased when combined with Dexmethylphenidate."
Clinical Note
moderateBretylium + Methylphenidate
"Bretylium may decrease the antihypertensive activities of Methylphenidate."
Clinical Note
moderateCyamemazine + Methylphenidate
"The risk or severity of adverse effects can be increased when Cyamemazine is combined with Methylphenidate."
Clinical Note
moderateSulpiride + Methylphenidate
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.
Immediate-release: 2–3 hours; Extended-release: 3–4 hours (drug), 6–8 hours (beaded forms). Context: Short half-life necessitates multiple daily dosing; sustained-release formulations prolong duration.
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%.
Renal: 90% (mostly as metabolites, primarily ritalinic acid), Fecal: <2%, Unchanged drug in urine: ~1%
Category C
Category A/B
CNS Stimulant
CNS Stimulant
"The risk or severity of adverse effects can be increased when Sulpiride is combined with Methylphenidate."