Feline Infectious Peritonitis in Cats
Feline Infectious Peritonitis in Cats - Symptoms, Causes, Diagnosis, Treatment, Recovery, Management, Cost
What are Feline Infectious Peritonitis?
When first infected by feline coronavirus, a cat may not show any symptoms of illness, even as the cat’s body is developing an immune response. A mutation of the virus or an issue with the cat’s immune response can trigger FIP, causing the cat to become noticeably ill over time.
About five to ten percent of cats that are infected with the coronavirus develop feline infectious peritonitis. FIP occurs most often in multi-cat homes and in shelters, and most often affects cats with a weakened immune system. Cat owners and shelter owners should all know what FIP looks like so they can minimize the risk of infection.
Feline infectious peritonitis (FIP) is a viral disease caused by feline coronavirus (FCoV). Not all strains of FCoV cause illness; those that do not are called feline enteric coronavirus.
Feline Infectious Peritonitis Average Cost
From 383 quotes ranging from $300 - $2,000
Average Cost
$800
Wag Compare logo

Get a free pet insurance quote in less than 60 seconds!

Easily compare quotes from the most trusted pet insurance companies in the United States.

Get a quote

background
Symptoms of Feline Infectious Peritonitis in Cats
The cat becoming ill with FIP shows no symptoms at first. Soon, it displays mild symptoms, such as nasal discharge, sneezing, and watery eyes that may look like a cold. Other cats develop intestinal symptoms such as diarrhea. Only a few cats go on to develop full-blown FIP, which may not happen until weeks or years after initial exposure. Because cats are able to hide illness so well, the slow onset of illness may seem to be sudden, with symptoms becoming more severe as the days pass:
  • Weight loss
  • Fever
  • Hair coat becomes rough
  • Loss of appetite
  • Depression
Types
Two types of feline infectious peritonitis affect cats, each with unique symptoms:
Effusive (wet) Form
  • Swollen abdomen from accumulation of fluid
  • Accumulation of fluid in chest (more rare)
  • Lethargy
  • Difficulty breathing
  • Rapid worsening of symptoms
Non-effusive (dry) Form
  • Persistent fever
  • Weight loss
  • Anemia
  • Depression
Because each cat shows different symptoms with FIP, it can be challenging for the vet to determine the correct diagnosis. 
Causes of Feline Infectious Peritonitis in Cats
FCoV causes some cats to develop FIP. FCoV infection is much more common than FIP infection. It’s when the virus mutates within the exposed cat’s body that the virus develops the potential to cause the cat to develop feline infectious peritonitis. Signs of FIP can affect various areas of the cat’s body:
  • Eyes
  • Abdomen
  • Chest cavity
  • Inflammation in the brain
  • Inflammation of the kidneys
  • Inflammation of the eyes
  • Inflammation of the liver
Diagnosis of Feline Infectious Peritonitis in Cats
Because FIP looks so much like other illnesses, vets don’t have a single, definitive test that tells them when a cat has developed this disease. Instead, three blood tests let the vet know that FCoV is present as antibodies in the cat. Even knowing this, the vet doesn’t know which strain of FCoV the cat has.
If the vet is suspicious that the cat has been exposed to FCoV, they can administer the immunoperoxidase test. The polymerase chain reaction test helps to point out genetic material from viruses in body fluids and tissues. 
The only way to arrive at a definite diagnosis of FIP is through biopsy of body tissues. If the cat had FIP and died, the vet can examine its tissues during an autopsy. This means vets have to rely on the cat’s history, its symptoms and by lab examination of accumulated fluids during visits to the veterinary office. This is known as a “presumptive diagnosis” when vets tell cat owners, “It looks like FIP.”
Other blood work the vet can order may include plasma protein findings of hyperglobulinemia and hyperfibrinogenemia. Corona viral antibody titers and histopathology findings may also help the vet arrive at a presumptive diagnosis of FIP. They may also take X-rays to study fluid effusions in the chest cavity and abdomen.
Treatment of Feline Infectious Peritonitis in Cats
At this time, no effective treatment or cure for FIP has been found or developed. Instead, vets will aim for short-term remission of symptoms in those cats whose symptoms are still fairly mild. In the end, FIP is fatal. 
Treatment is supportive, including nutritive care and nursing support. Veterinary staff works to slow down the cat’s inflammatory response to the virus.
Medications include corticosteroids, antibiotics and cytotoxic medications. The cat may undergo fluid therapy to drain accumulated fluid from its chest or abdominal cavity. It may also receive blood transfusions.
At this time, researchers are testing immunosuppressive drugs that may slow the progress of FIP. The same search is going on for effective antiviral medications to either slow down the replication of the virus itself or to completely prevent replication. One study focuses on the combination of an immunosuppressive drug and an antiviral drug to be given at the same time.
Once the cat has been diagnosed, its family should reduce the cat’s level of stress in the home. They should provide the tastiest, high-protein (all meat) diet and monitor the cat’s weight, activity level and appetite as well.
Cat owners should resist giving their cats homeopathic treatments or medications for which effectiveness and safety are unknown. 
Petted logo

Worried about the cost of treating your pet's symptoms?

Pet Insurance covers the cost of many common pet health conditions. Prepare for the unexpected by getting a quote from top pet insurance providers.

Get a quote

background
Recovery of Feline Infectious Peritonitis in Cats
Because FIP is known to be fatal, cat owners should work to keep their cat as comfortable as possible. Cats with “dry” FIP may live longer than those with “wet” FIP.
The best strategy in multi-cat households, catteries, and shelters is to prevent the exposure of healthy kittens and cats to FCoV-positive cats and kittens. Once the cats have finished eating, collect all food dishes and wash them thoroughly. Designate one litter box for the FCoV-positive cat only. Permit the healthy cats to share the remaining litter boxes and keep them all clean. Clean litter boxes thoroughly between cat litter changes.
Cat owners can use common household disinfectants, bleach and quaternary ammonium compounds to clean and disinfect all areas where the cats play and sleep on a daily basis. Finally, don’t allow household cats to roam outdoors, where they may come into contact with an FCoV-positive cat.
Feline Infectious Peritonitis Average Cost
From 383 quotes ranging from $300 - $2,000
Average Cost
$800
arrow-up-icon
Top
Feline Infectious Peritonitis Questions and Advice from Veterinary Professionals
dog-breed-icon
Birman
dog-name-icon
Milo
dog-age-icon
2 Years
thumbs-up-icon

5 found this helpful

thumbs-up-icon

5 found this helpful

My pet has the following symptoms:
Lethargy, No Appetite, Weight Loss
My cat passed away after 3mths of runny poop, lethargy, no appetite, isolating himself. Bloods and x rays showed nothing . Post mortem showed his lungs had filled with fluid. One vet said fip because of the fluid but the vet who did the post mortem said his organs were all in perfect condition and there was no fluid in his abdomen. My question is could a cat die from fip with his organs all unaffected?
Aug. 16, 2018
Answered by Dr. Michele K. DVM
5 Recommendations
There are different forms of FIP, and Milo may have had a form that caused fluid to build up in his lungs. I"m sorry that that happened to him, that is very sad.
Aug. 16, 2018
Was this question and answer helpful?
dog-breed-icon
Domestic shorthair
dog-name-icon
Finley
dog-age-icon
8 Months
thumbs-up-icon

1 found this helpful

thumbs-up-icon

1 found this helpful

My pet has the following symptoms:
Depression
Weight Loss
Vomiting
Eye Discharge
Not Eating
Tired
Anorexia
Depressed
Fast Breathing
Not Moving
Red Paw Pads
My cat has been throwing up for a few weeks, it was normally only one a day but he would act normal afterwards and still eat and drink. Since Friday he's been going down hill. The last time he ate something was Saturday at 4:30pm, he had tuna and was sick every 4 hours after that. He then calmed down and hasn't thrown up since Sunday 1pm. First he was drinking quite a bit but now he hasn't ate or drank for 24 hours now and hasn't eaten since Saturday. All he wants to do is to hide away and when I put food out he acts interested and sometimes starts to pur but he refuses to eat still.
July 31, 2018
1 Recommendations
You should visit your Veterinarian to be on the safe side since the symptoms are quite severe and Finley is quite young still; a viral infections is a concern, but I cannot make a diagnosis without examining him thoroughly. Until you’re able to visit your Veterinarian, try to give a little water drop by drop to the mouth using a syringe. Regards Dr Callum Turner DVM
July 31, 2018
Was this question and answer helpful?
dog-breed-icon
Domestic longhair
dog-name-icon
Pandora
dog-age-icon
1 Year
thumbs-up-icon

0 found this helpful

thumbs-up-icon

0 found this helpful

My pet has the following symptoms:
Weight Loss,
Weight Loss, Lethargy
Weight Loss, Lethargy, Rough Fur
Pandora went from 11 pounds in August, when I had her nails trimmed at the vet, to 8 pounds in November when we noticed that she had lost weight and just wasn't acting like herself. She wasn't eating much and was just laying around. She quit playing with her new "brother", Genji. I took her to the vet and he said that she MIGHT have it, but refused to do any testing at all. Gave her a shot of steroids, some fluids under the skin, and antibiotics. She didn't get any better and a couple of days later I took her to a different vet, while this vet did concur with the first one, he at least did some blood work to check on her organs and at that time her organs were doing OK. He switched her antibiotic and gave her more fluids. That was on Saturday, by Monday morning Pandora was worse.I took her back to the second vet and they re-ran the bloodwork. I also had them do an ultrasound on her belly. They called me later and said that her organs were starting to fail and that the ultrasound showed that the fluid in her belly was sticky looking. They recommended euthanasia. My beautiful Pandora was only 13 months old when she joined my other cats at the rainbow bridge.
dog-breed-icon
Bengal
dog-name-icon
Amber
dog-age-icon
11 Months
thumbs-up-icon

0 found this helpful

thumbs-up-icon

0 found this helpful

My pet has the following symptoms:
Pain
Sneezing
Difficulty Walking
Difficulty Breathing
We got a cat from the shelter, he was with us for about 3 months. He had a hard past and was very happy with us for the final months of his life. He all of a sudden started showing signs of a sickness, we took him to the vet. They ran a bunch of tests on him and diagnosed him with FIP. There was a lot of fluid in his chest cavity. We made the choice of putting him to sleep. He is a critically endangered species, bengals are very rare.
dog-breed-icon
Bombay
dog-name-icon
Kovi
dog-age-icon
5 Years
thumbs-up-icon

0 found this helpful

thumbs-up-icon

0 found this helpful

My pet has the following symptoms:
Swollen Belly
Kovi's belly started to swell quickly. He is very swollen but other than that he's ok. He eats. Still walks to cat box and still grooms himself. The vet came out 3 weeks ago and said he still had life so she chose not to put him down. Other than his giant belly he seems fine. Would it be reasonable to have it drained?
dog-breed-icon
Maine Coone
dog-name-icon
Zingo
dog-age-icon
4 Years
thumbs-up-icon

0 found this helpful

thumbs-up-icon

0 found this helpful

My pet has the following symptoms:
Fluid In Abdomen
Breathing Difficulties
Open Mouth
Our family cat died of FIP a few years back. Everything had seemed perfectly okay with him, we hadn’t noticed any strange behaviour or anything odd or unusual in his habits. He was, in our eyes, a perfectly healthy cat. One evening he started breathing with his mouth open and since it hadn’t passed after an hour, we decided to call and consult a vet. They told us to bring him in immediately and we did. He got loads of pain killers and was very calm through the whole process thankfully, and we were all there with his favourite toys and held his paw throughout it all. On the X-ray you could see the amount of fluid in his chest and abdomen - his body had turned into a mess. We made the decision to let him go after seeing that and while it was hard on us, it wasn’t a difficult decision to make. FIP is fatal and making him suffer just to give us more time with him would’ve been extremely selfish. He fell asleep surrounded by the people who loved him the most, all petting him and with his toys all around him.
Feline Infectious Peritonitis Average Cost
From 383 quotes ranging from $300 - $2,000
Average Cost
$800
Wag Compare logo

Get a free pet insurance quote in less than 60 seconds!

Easily compare quotes from the most trusted pet insurance companies in the United States.

Get a quote

background
Need pet insurance?
Need pet insurance?

Learn more in the Wag! app

Five starsFive starsFive starsFive starsFive stars

43k+ reviews

Install


© 2025 Wag Labs, Inc. All rights reserved.


© 2025 Wag Labs, Inc. All rights reserved.