Comparative Pharmacology
Head-to-head clinical analysis: FAMCICLOVIR versus SYMMETREL.
Peer-Reviewed Evidence
Head-to-head clinical analysis: FAMCICLOVIR versus SYMMETREL.
FAMCICLOVIR vs SYMMETREL
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Famciclovir is a prodrug of penciclovir, which inhibits viral DNA polymerase by competing with deoxyguanosine triphosphate, thus inhibiting viral DNA replication. It has activity against herpes simplex virus (HSV-1, HSV-2), varicella-zoster virus (VZV), and Epstein-Barr virus (EBV).
Inhibits influenza A virus uncoating and viral RNA replication; increases dopamine release and blocks dopamine reuptake in the CNS.
500 mg orally three times daily for 7 days for herpes zoster; 125 mg twice daily for 5 days for recurrent genital herpes; 250 mg three times daily for 7 days for first-episode genital herpes; 500 mg twice daily for 7 days for recurrent herpes labialis.
100 mg orally twice daily; may increase to 200 mg orally twice daily if tolerated, usually in divided doses. For Parkinson's disease, 100 mg orally twice daily; for drug-induced extrapyramidal reactions, 100 mg orally twice daily.
None Documented
None Documented
Clinical Note
moderateFamciclovir + Sulfisoxazole
"The metabolism of Sulfisoxazole can be decreased when combined with Famciclovir."
Clinical Note
moderateFamciclovir + Erythromycin
"The metabolism of Erythromycin can be decreased when combined with Famciclovir."
Clinical Note
moderateFamciclovir + Cyclosporine
"The metabolism of Cyclosporine can be decreased when combined with Famciclovir."
Clinical Note
moderateFamciclovir + Fluconazole
Terminal half-life of penciclovir is 2-3 hours in healthy adults, prolonged to 3-6 hours in hepatic impairment and >20 hours in severe renal impairment (CrCl <30 mL/min), requiring dose adjustment.
Terminal half-life: 24-48 hours (young adults); 48-72 hours (elderly); may extend to 7-10 days in severe renal impairment. Clinically, steady-state achieved in 4-7 days.
Renal elimination: ~60% as penciclovir (active metabolite) and <10% as unchanged famciclovir; biliary/fecal: <5%; the remainder is metabolized to inactive compounds.
Primarily renal excretion (90-95% unchanged) via glomerular filtration and tubular secretion; minor fecal (<5%). Dose adjustment required in renal impairment.
Category A/B
Category C
Antiviral
Antiviral and Antiparkinsonian
"The metabolism of Fluconazole can be decreased when combined with Famciclovir."