Famvir Disease Interactions

Penciclovir, the active antiviral metabolite of famciclovir, is primarily eliminated by the kidney. Acute renal failure has been reported in patients with underlying renal disease who did not receive an appropriate dosage reduction. Dosage adjustments are recommended for patients with moderate to severe renal impairment (CrCl < 60 mL/min).

Famciclovir is converted by the liver to the active antiviral metabolite, penciclovir. The bioavailability of penciclovir following a dose of famciclovir was not affected in patients with well-compensated chronic liver disease. However, there are no data on the pharmacokinetic disposition of famciclovir in patients with severe uncompensated liver disease. Therapy with famciclovir should be administered cautiously in these patients, since the clinical significance of possible famciclovir accumulation is unknown. Theoretically, famciclovir may also not be effective in these patients.