Famciclovir
Also known as: Famvir
* **Administration**: You can give this medication with or without food. If it causes stomach upset, giving it with a small treat or meal may help. * **Expectations**: Feline herpesvirus (FHV-1) is a lifelong condition. This medication helps control the active flare-up and reduce symptoms (like sneezing, eye discharge, and ulcers), but it does not cure the virus. Recurrences may still happen during times of stress. * **Monitoring**: Watch for signs of decreased appetite or increased thirst. Since experience with this drug in cats is still growing, please report any unusual side effects to your veterinarian immediately.
Dosage must be set by your veterinarian for your specific pet. Never give human medication or another pet’s prescription without veterinary guidance.
What it is used for
- Feline herpes virus (FHV-1)
- Adjunctive treatment of FHV-1 rhinotracheitis
- Chronic, recurrent and/or severe herpes viral infection
- Feline herpes virus (FHV-1)
- Adjunctive treatment (with interferon and lysine) of herpes virus-associated ulcerative facial dermatitis & stomatitis
- Management of feline herpesvirus (FHV-1) infections
How it is given
Possible side effects
- Cats: Anorexia and polydipsia (noted at high doses of 90 mg/kg PO q8h)
- Humans: Nausea, vomiting, diarrhea, headache, neutropenia, renal failure
- Gastrointestinal signs (vomiting, diarrhea, anorexia)
Cautions & contraindications
- Known hypersensitivity to famciclovir or penciclovir
- > **Caution in Renal Impairment**: Famciclovir is primarily excreted by the kidneys. Dosage adjustments are highly recommended for patients with renal dysfunction (e.g., CrCl < 40 mL/min in humans). * **Pregnancy/Nursing**: FDA Category B in humans. Animal studies up to 1,000 mg/kg/day showed no embryo/fetal effects. Excreted in the milk of rats; clinical significance for nursing offspring is unclear.
Drug interactions
- Probenecid: Can reduce the amount of penciclovir excreted by the kidneys, leading to increased penciclovir plasma levels
Frequently asked questions
What is Famciclovir used for in pets?
* **Administration**: You can give this medication with or without food. If it causes stomach upset, giving it with a small treat or meal may help. * **Expectations**: Feline herpesvirus (FHV-1) is a lifelong condition. This medication helps control the active flare-up and reduce symptoms (like sneezing, eye discharge, and ulcers), but it does not cure the virus. Recurrences may still happen during times of stress. * **Monitoring**: Watch for signs of decreased appetite or increased thirst. Since experience with this drug in cats is still growing, please report any unusual side effects to your veterinarian immediately.
Is Famciclovir safe for my pet?
Dosage must be set by your veterinarian for your specific pet. Never give human medication or another pet’s prescription without veterinary guidance.
This article is for general education and is not a substitute for professional veterinary advice. If your pet is unwell, please consult a veterinarian.
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