Cat Health

FIP

What I've learned caring for cats with FIP, in plain language. This reflects personal experience, not veterinary advice — please talk to your vet if you suspect it.

< 2%

of cats carry the mutation

Not contagious

to other cats or animals

Genetic

a cat must be born with the gene

No litter-box spread

cannot pass through shared litter

FIP (Feline Infectious Peritonitis) is a mutation of the feline coronavirus. It is not contagious to other felines or any other animal, and cannot be transferred through the sharing of litter boxes.

The good news

Treatment exists — and it works

Before 2020 there was no cure for FIP. Thanks to research from scientists at Gilead Sciences and Dr. Niels Pedersen at UC Davis, treatment has been available since 2020.

GS-441524

the antiviral treatment

93% success

if symptoms are caught early

84 days

the full course must be run

FIP is most common in kittens 4–10 months old, but it can affect very young kittens, adult cats, and senior cats as well.

Four presentations

Types of FIP

Tap a type to see its symptoms and how it's diagnosed.

Wet FIP

Symptoms

  • Fever
  • Lethargy
  • Loss of appetite
  • Distended abdomen
  • Pleural effusion (fluid in the lungs) — labored breathing will be present
  • If pleural effusion is present, the lungs must be tapped.

Never tap fluid out of the abdomen.

Diagnosis — A CBC and full panel, or fluid removed from the abdomen confirming a yellow, straw-colored fluid.

Dry FIP

Symptoms

  • “Skeletor” body — angular face, boney spine
  • Tacky fur
  • Fever
  • Lethargy
  • Loss of appetite
  • Rapid weight loss
  • Jaundice
  • Dehydration
  • Resistant diarrhea
  • Recurring vomiting

Diagnosis — Harder to diagnose than other types — a CBC and full panel must be completed to accurately diagnose.

Neuro FIP

Symptoms

  • Lethargy
  • Loss of appetite
  • Loss of limb function (generally back legs first)
  • Wobbly walk
  • Often sits in a “hunched” position
  • Complete immobility
  • Seizures

Diagnosis — A CBC and full blood panel.

Ocular FIP

Symptoms

  • Pupils that stay dilated
  • Pupils that involuntarily constrict and dilate
  • Inflammation of the eyes
  • Cloudiness of the eyes
  • Blindness

Diagnosis — A CBC and full blood panel.

Watch for these

FIP triggers

  • Spay/neuter surgery

    The most common trigger — symptoms can appear anywhere from 2 hours to 2 days after surgery.

  • Environmental changes

  • Illness

  • Any type of surgery

  • Stressful situations

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