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Famciclovir

Famvir

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Sourced from primary literature. Awaiting credentialed clinical reviewer — our editorial process.

Drug Class

Antiviral

Routes

PO

Indications

FHV-1 dermatitisFHV-1 infectionsFHV-1 ophthalmologic (keratitis)Herpesvirus (investigational)

Mechanism of Action

Prodrug of penciclovir. Inhibits viral DNA polymerase in herpesvirus. Used for feline herpesvirus-1 (FHV-1) infections.

Side effects & warnings

First-line antiviral for FHV-1 in cats. Higher doses needed in cats (90mg/kg) due to lower conversion to penciclovir. Well tolerated. May cause GI upset.

Species with Famciclovir dosing data (4 dose rules)

Cat (Domestic)Rabbit (Domestic)

Evidence levels across 4 dose rules

Moderate×1Strong×2Extrapolated×1

Each ExoticRx dose rule is graded by the strength of its primary evidence — see the editorial process.

Backed by 2 published primary sources

  • · Carpenter's Exotic Animal Formulary, 6th Ed
  • · Plumb's Veterinary Drug Handbook, 9th Ed

Sample dosing (2 of 4 cited rules)

Free-tier preview — dog and cat dosing. Pro and Student unlock all 2 species including reptiles, birds, pocket pets, livestock, and equine.

SpeciesRouteDoseFrequencyEvidenceSource
Cat (Domestic)PO40–90 mg/kgq8-12hStrongPlumb's Veterinary Drug Handbook, 9th Ed
Cat (Domestic)PO90 mg/kgq8hStrongPlumb's Veterinary Drug Handbook, 9th Ed

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