The final stages of dry FIP involve severe organ damage, leading to profound lethargy, complete anorexia, paralysis, seizures, blindness, and eventual collapse, as inflammation creates granulomas in the brain (CNS), eyes, liver, kidneys, and other organs, causing system failure and intense suffering, typically progressing rapidly without treatment.
There are two forms or types of FIP, a wet and dry form. The symptoms in both types include vague signs such as decreased appetite, weight loss, lethargy and fever. The dry form may also have symptoms such as seizures or difficulty walking (ataxia).
Feline infectious peritonitis is considered an incurable disease with survival times varying from days to weeks for the effusive form, and weeks to months for the non-effusive form (2,12–14).
Forms of FIP in cats
In some cases, dry FIP can turn into wet FIP, and the reverse can also happen. The two forms of FIP tend to have different symptoms and present differently. Wet FIP involves fluid buildup in the body, most often in the abdominal cavity. And wet FIP tends to develop very quickly.
Cats who do not get treatment for FIP will die of the disease within 10 days or less in most cases. The survival time of cats with wet feline infectious peritonitis is generally days to weeks, while dry FIP has a longer survival time of weeks to months.
Once diagnosed with FIP, many veterinarians will recommend euthanizing your cat to avoid unnecessary pain. However, if the disease is allowed to develop to its later stages the symptoms are quite extreme. Cats with dry, or non-effusive FIP may be unable to walk, unable to see and may ultimately become paralyzed.
The final stage signs that show a cat approaching the end of life include: Unresponsiveness or lack of alertness. Shallow breathing, gasping, or death rattle.
If the eyes are affected (ocular FIP) they may look cloudy, bloody or with different pupil sizes, and the cat may show signs of pain such as holding the eye or eyes closed.
Symptoms overlap with FeLV, FIV, IBS, and cancer. But knowing the subtle differences can save your cat's life.
Watch for FIV-cat symptoms such as sneezing, unusual urination, poor coat condition, lack of appetite, inflammation of the gums and mouth, and diarrhea, and promptly visit the vet if these issues arise, says Jefferson.
Look for these signs:
There are two major forms of FIP, an effusive, or “wet” form and a noneffusive, or “dry” form. Regardless of which form they ultimately progress to develop, cats infected with FIPV usually first develop nonspecific signs of disease such as loss of appetite, weight loss, depression, and fever.
The top "silent killers" in cats are Chronic Kidney Disease (CKD), often progressing until 75% kidney failure, and Hypertrophic Cardiomyopathy (HCM), a heart muscle disease, both often showing few symptoms until advanced stages, along with Hypertension (High Blood Pressure) and Hepatic Lipidosis (Fatty Liver), leading to sudden illness or organ failure if undetected. Early detection through regular vet check-ups, blood tests, and monitoring for subtle changes like increased thirst/urination, weight loss, or hiding is crucial for managing these common, often hidden, feline diseases, says this article.
Symptoms of Kidney Failure in Cats
Early Signs of FIP Relapse
Weight loss, even with normal food intake. Recurrent fevers above 39.5 °C (103.1 °F) A swollen abdomen or fluid buildup. Neurological symptoms: unsteady walking, wobbling, or seizures.
However, seizures were significantly more frequent in animals with marked extension of the inflammatory lesions to the forebrain (P=0.038). Thus, the occurrence of seizures in FIP indicates extensive brain damage and can, therefore, be considered to be an unfavourable prognostic sign.
General Signs of End-Stage FIP. Cats with end-stage FIP may exhibit lethargy, weight loss, anorexia, high fever and jaundice.
It is not recommended to euthanize a cat, even with FIP, as long as it looks and acts fairly normal. Miracles do happen, but they can't happen unless they are provided time to happen. However, some owners choose to end suffering at an earlier stage, given the grave prognosis.
Feline Leukemia (FeLV) is much more devastating than FIV. This is because FeLV typically results in cancer, leukemia, and severe bone marrow suppression in young cats. The one commonality between FELV & FIV is that there is no cure for either.
Cats with wet FIP have a pot-bellied appearance due to effusion, the build up of fluid in the abdomen. The effusion is straw colored and thick, and the abdomen feels like a water balloon (as opposed to a pot-bellied kitten who is bright and alert, but has intestinal parasites or is gassy or well-fed).
To say "I love you" in cat language, use slow blinks, offer gentle head/cheek rubs (scent glands), let them initiate contact, provide interactive play, and simply share calm presence, mimicking their natural affection signals like grooming and trust-building.
Signs That a Cat is in Pain
Frequent or ongoing meowing or howling. Litter box accidents, urinating outside of their litterbox. Tail flicking. Won't eat or reduced appetite.
The 3-3-3 rule for cats is a guideline for new adopters, suggesting it takes 3 days for a cat to decompress and feel safe, 3 weeks to learn the routine and start showing personality, and 3 months to feel truly at home, building trust and a strong bond. It helps manage expectations during the adjustment period, emphasizing patience, consistency (with routines), and providing a secure, calm environment (like a single "safe" room initially) for your new feline friend.
You can sometimes recognize when a cat is saying goodbye through their behavior. Cats often display distinctive behaviors when saying goodbye, such as seeking unusual amounts of attention or finding isolated spots to rest.
Cats do seem to be aware of death, but it is hard to know how much they understand the concept and whether they fully understand the finality of their own passing. They certainly understand when they are feeling ill or that something is different or wrong.