Comparative Pharmacology
Head-to-head clinical analysis: AMANTADINE versus INBRIJA.
Peer-Reviewed Evidence
Head-to-head clinical analysis: AMANTADINE versus INBRIJA.
AMANTADINE vs INBRIJA
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Amantadine is an antiviral and antiparkinsonian agent. Its antiviral mechanism involves inhibition of viral uncoating, thereby blocking influenza A M2 ion channel. In Parkinson's disease, it is thought to increase dopamine release and inhibit its reuptake, and may also have anticholinergic and NMDA receptor antagonist effects.
INBRIJA (levodopa inhalation powder) is a combination of levodopa, an aromatic amino acid, and a prodrug of dopamine, which is decarboxylated to dopamine in the brain, thereby restoring dopamine levels in the striatum and improving motor function in Parkinson disease.
100 mg orally twice daily for Parkinson's disease; 100 mg orally twice daily for influenza A prophylaxis/treatment (up to 200 mg/day).
Inhaled levodopa powder, 84 mg (two 42 mg capsules) inhaled orally via the INBRIJA inhaler as needed for OFF episodes, up to 5 times per day. Maximum daily dose: 420 mg (5 doses).
None Documented
None Documented
Clinical Note
moderateAmantadine + Haloperidol
"The therapeutic efficacy of Haloperidol can be decreased when used in combination with Amantadine."
Clinical Note
moderateAmantadine + Mifepristone
"Amantadine may increase the QTc-prolonging activities of Mifepristone."
Clinical Note
moderateAmantadine + Promazine
"The therapeutic efficacy of Promazine can be decreased when used in combination with Amantadine."
Clinical Note
moderateAmantadine + Chlorpromazine
Terminal elimination half-life: 10-14 hours in young adults, up to 24 hours in elderly; prolonged to >24 hours in renal impairment
0.75–1.5 hours (terminal elimination half-life of levodopa). Short half-life necessitates frequent dosing or continuous dopaminergic stimulation strategies.
Renal: 90% as unchanged drug via glomerular filtration and tubular secretion; fecal: <10%
Primarily renal excretion of metabolites and unchanged drug. Approximately 80% of a dose is recovered in urine as levodopa metabolites (mainly 3-O-methyldopa and vanilpyruvic acid) and <10% as unchanged levodopa. Fecal excretion accounts for <5%.
Category C
Category C
Antiviral / Antiparkinsonian
Antiparkinsonian
"The therapeutic efficacy of Chlorpromazine can be decreased when used in combination with Amantadine."