Comparative Pharmacology
Head-to-head clinical analysis: DEXEDRINE SPANSULE versus MODAFINIL.
Peer-Reviewed Evidence
Head-to-head clinical analysis: DEXEDRINE SPANSULE versus MODAFINIL.
DEXEDRINE SPANSULE vs MODAFINIL
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Dextroamphetamine is a central nervous system (CNS) stimulant that increases synaptic concentrations of norepinephrine and dopamine by blocking their reuptake and promoting release from presynaptic terminals.
The precise mechanism of action is unknown. Modafinil is a wakefulness-promoting agent that may have direct or indirect effects on dopamine, norepinephrine, serotonin, GABA, glutamate, and orexin systems. It binds to the dopamine transporter and inhibits dopamine reuptake.
5-60 mg orally once daily in the morning, using extended-release capsules.
200 mg orally once daily in the morning.
None Documented
None Documented
Terminal elimination half-life is 6-8 hours in adults, 10-13 hours in children, and prolonged in alkaline urine (up to 16-20 hours) due to enhanced tubular reabsorption. In hepatic impairment, half-life may extend to 12-15 hours. Steady-state is reached within 2-3 days.
Clinical Note
moderateArmodafinil + Estrone sulfate
"The serum concentration of Estrone sulfate can be decreased when it is combined with Armodafinil."
Clinical Note
moderateModafinil + Estrone sulfate
"The serum concentration of Estrone sulfate can be decreased when it is combined with Modafinil."
Clinical Note
moderateModafinil + Sulfisoxazole
"The metabolism of Sulfisoxazole can be decreased when combined with Modafinil."
Clinical Note
moderateModafinil + Erythromycin
Terminal elimination half-life is approximately 15 hours (range 10–30 hours). This supports once-daily dosing for sustained wakefulness.
Renal excretion of unchanged drug (approximately 30-40% unchanged) and hepatic metabolism to inactive metabolites (primarily hippuric acid, benzoic acid, and hydroxylated derivatives). About 90% of a dose is excreted in urine within 48 hours, with 10-15% as unchanged dextroamphetamine; minor biliary/fecal elimination (<5% total).
Primarily renal (as metabolites and unchanged drug); approximately 80% of the dose is recovered in urine, with less than 10% as unchanged modafinil. Fecal excretion accounts for less than 1%.
Category C
Category C
CNS Stimulant
CNS Stimulant
"The metabolism of Erythromycin can be decreased when combined with Modafinil."