Comparative Pharmacology
Head-to-head clinical analysis: AMANTADINE versus VALACYCLOVIR HYDROCHLORIDE.
Peer-Reviewed Evidence
Head-to-head clinical analysis: AMANTADINE versus VALACYCLOVIR HYDROCHLORIDE.
AMANTADINE vs VALACYCLOVIR HYDROCHLORIDE
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.
Valacyclovir hydrochloride is a prodrug of acyclovir. After oral administration, it is rapidly converted to acyclovir, which inhibits viral DNA polymerase, leading to chain termination and inhibition of viral DNA replication.
100 mg orally twice daily for Parkinson's disease; 100 mg orally twice daily for influenza A prophylaxis/treatment (up to 200 mg/day).
500 mg orally twice daily for recurrent genital herpes; 1 g orally twice daily for herpes zoster; 1 g orally three times daily for herpes simplex encephalitis or immunocompromised patients.
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
Terminal elimination half-life: 2.5–3.3 hours in patients with normal renal function; prolonged to 14 hours in renal impairment (CrCl 15–30 mL/min).
Renal: 90% as unchanged drug via glomerular filtration and tubular secretion; fecal: <10%
Renal excretion: >90% as unchanged drug and inactive metabolite (9-carboxymethoxymethylguanine). Biliary/fecal: <2%.
Category C
Category A/B
Antiviral / Antiparkinsonian
Antiviral
"The therapeutic efficacy of Chlorpromazine can be decreased when used in combination with Amantadine."