Famciclovir (Rx)

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Famciclovir (Rx)

Why our vets recommend it

Famciclovir is an antiviral medication used to improve the symptoms of feline herpes virus.

 
 
 
 

Medication information

What is Famciclovir?

Famciclovir is a prescription antiviral drug vets typically prescribe to treat cats suffering from feline herpes virus (FHV-1). It helps reduce the symptoms of the virus, such as eye issues like conjunctivitis. This is an FDA-approved drug for humans that’s regularly prescribed for cats.

What does Famciclovir treat?

Common symptoms that Famciclovir treats include:

  • Sneezing
  • Congestion
  • Conjunctivitis (pink eye)
  • Excessive blinking
  • Squinting
  • Runny nose
  • Eye discharge

Conditions that Famciclovir treats include:

  • Feline herpes virus (also known as FHV-1, feline viral rhinotracheitis, or FVR)

How is Famciclovir given?

Give Famciclovir to pets orally, with or without food, according to the vet’s instructions.

Who is Famciclovir for?

Cats

What are the active ingredients of Famciclovir?

The active ingredient is famciclovir.

What are the possible side effects of Famciclovir in cats?

The most common side effects of famciclovir in cats include decreased appetite, vomiting, diarrhea, and increased drinking (which may lead to increased urination). If you have any questions or concerns about side effects, please contact your vet.

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Safety Information

  • This is a human medication used off-label in cats. Monitor for gastrointestinal side effects. Periodic blood work may be recommended during extended treatment.

Warnings 

  • For veterinary use only under professional supervision.

  • Not FDA-approved for cats but legally prescribed off-label.

Human Warnings

  • While famciclovir is also used in human medicine, do not take medication prescribed for your pet. Human and veterinary formulations differ in dosage and concentration.


References

  1. "Famciclovir for Cats." PetMD, www.petmd.com/pet-medication/famciclovir. 
  2. Warren, Rob. "Antiviral Discovered to Speed Recovery and Reduce Corneal Disease in Kittens with Herpesvirus." School of Veterinary Medicine, 1 Nov. 2024, www.vetmed.ucdavis.edu/news/antiviral-discovered-speed-recovery-and-reduce-corneal-disease-kittens-herpesvirus.