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Famciclovir Disease Interactions

There are 2 disease interactions with famciclovir:


Famciclovir (Includes Famciclovir) ↔ Renal Dysfunction

Severe Potential Hazard, High plausibility

Applies to: Renal Dysfunction

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).


  1. "Product Information. Famvir (famciclovir)." SmithKline Beecham, Philadelphia, PA.
  2. Gill KS, Wood MJ "The clinical pharmacokinetics of famciclovir." Clin Pharmacokinet 31 (1996): 1-8
  3. Boike SC, Pue MA, Freed MI, Audet PR, Fairless A, Ilson BE, Zariffa N, Jorkasky DK "Pharmacokinetics of famciclovir in subjects with varying degrees of renal impairment." Clin Pharmacol Ther 55 (1994): 418-26

Famciclovir (Includes Famciclovir) ↔ Liver Disease

Moderate Potential Hazard, Moderate plausibility

Applies to: Liver Disease

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.


  1. Gill KS, Wood MJ "The clinical pharmacokinetics of famciclovir." Clin Pharmacokinet 31 (1996): 1-8
  2. "Product Information. Famvir (famciclovir)." SmithKline Beecham, Philadelphia, PA.
  3. Boike SC, Pue M, Audet PR, Freed MI, Fairless A, Ilson BE, Zariffa N, Jorkasky DK "Pharmacokinetics of famciclovir in subjects with chronic hepatic disease." J Clin Pharmacol 34 (1994): 1199-207
  4. Perry CM, Wagstaff AJ "Famciclovir - a review of its pharmacological properties and therapeutic efficacy in herpesvirus infections." Drugs 50 (1995): 396-415
View all 4 references

famciclovir drug Interactions

There are 10 drug interactions with famciclovir

Drug Interaction Classification

The classifications below are a general guideline only. It is difficult to determine the relevance of a particular drug interaction to any individual given the large number of variables.
Major Highly clinically significant. Avoid combinations; the risk of the interaction outweighs the benefit.
Moderate Moderately clinically significant. Usually avoid combinations; use it only under special circumstances.
Minor Minimally clinically significant. Minimize risk; assess risk and consider an alternative drug, take steps to circumvent the interaction risk and/or institute a monitoring plan.
Unknown No information available.

Do not stop taking any medications without consulting your healthcare provider.

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