Comparative Pharmacology
Head-to-head clinical analysis: AMPHETAMINE versus CONCERTA.
Peer-Reviewed Evidence
Head-to-head clinical analysis: AMPHETAMINE versus CONCERTA.
AMPHETAMINE vs CONCERTA
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Amphetamine is a central nervous system stimulant that promotes release of monoamines (dopamine, norepinephrine, and serotonin) from presynaptic terminals and inhibits their reuptake, leading to increased synaptic concentrations. It also reversibly inhibits monoamine oxidase (MAO) and may directly stimulate postsynaptic receptors.
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.
5-60 mg/day orally, divided into 2-3 doses; immediate-release: initial 5 mg once or twice daily, increase by 5 mg increments weekly; extended-release: initial 20 mg once daily in the morning, increase by 10 mg weekly
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
Clinical Note
moderateAmphetamine + Torasemide
"Amphetamine may increase the hypotensive activities of Torasemide."
Clinical Note
moderateAmphetamine + Tranilast
"Amphetamine may decrease the sedative activities of Tranilast."
Clinical Note
moderateHydroxyamphetamine + Tranilast
"Hydroxyamphetamine may decrease the sedative activities of Tranilast."
Clinical Note
moderateDextroamphetamine + Tranilast
"Dextroamphetamine may decrease the sedative activities of Tranilast."
Terminal elimination half-life: 10-13 hours (adults) for immediate-release formulations; prolonged to 12-14 hours in chronic use. Clinical context: Half-life correlates with duration of action; twice-daily dosing may be needed.
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.
Primarily renal (70-80% as unchanged drug and metabolites); minor biliary/fecal (approximately 2-5%). Urinary pH-dependent: acidic pH enhances elimination, alkaline pH reduces it.
Primarily renal (77%-87% as unchanged drug and metabolites); metabolic elimination accounts for 13%-23%, with minor biliary excretion (<2%).
Category D/X
Category C
CNS Stimulant
CNS Stimulant