Feline Infectious Peritonitis (FIP)

A contagious disease, that is always disease. Our best success is helping some cats feel OK. 


My cat Roger is real sick. He’s only about one year old and for the past 3 weeks he’s not been very active, and not eating very much. I think he has a fever too. Then his belly started to get kind of bloated looking. His doctor said that Roger might have F.I.P. Can we try antibiotics?


Dr. Nichol:

I am sorry to hear about Roger’s illness. He truly is quite sick. Unfortunately while there are a few medications that could help Roger, antibiotics will only help a little. First I will explain F.I.P.


F.I.P. stands for Feline Infectious Peritonitis. It is caused by a virus that is often transmitted to kittens by their mothers or by other adults cats. Cats at greatest risk are those who live in multiple cat households or in breeding catteries. Kittens who are born in these groups are at greatest risk. The worst news of all is that F.I.P. is a fatal disease. It causes a severe inflammation  of blood vessels. It can affect many internal systems like the kidneys, eyes, brain, and liver. But the symptoms most often seen are like those that Roger has; that is the effusive or “wet” form of F.I.P.  “Effusive” means that fluid accumulates in the abdomen or chest causing a bloated tummy (like Roger’s) or difficulty breathing (fluid in the chest). Although the fluid buildup is not usually painful, these kitties run fevers, feel badly, and have poor appetites.


What can we do for Roger? Since F.I.P. is an inflammatory disease with involvement of a cat’s immune system, drugs, like prednisone, that suppress the immune response could help Roger to feel better and live longer. Drainage of the fluid in his belly and a blood transfusion will also help. Most of all, you need to prepare for losing Roger some day. I am sorry. F.I.P. is not curable.


Lastly, there is a preventive for cats who are at risk. The FI.P. vaccine, which is given by nose drops, is moderately effective. It is best started when kittens are 16 weeks old, then boostered 3-4 weeks later. Since we don’t see much F.I.P., except in multiple cat households and catteries, an average house cat has no real need for vaccination. On the other hand, purebred kittens purchased from breeding operations or pet stores should be tested right away to be sure that they are free of the disease. Adult cats intended for breeding should be tested first, then vaccinated before being introduced into a group.