Feline Infectious Peritonitis, or FIP, is one of those diseases that sounds rare—until it affects your cat. While not every cat exposed to the feline coronavirus develops FIP, it’s a condition every cat parent should be aware of, especially in multi-cat households or shelters. The tricky part? FIP can look like a lot of other things at first.
At Atlas Animal Hospital, we often meet concerned cat parents who’ve never even heard of FIP until their vet brings it up. Our goal is to help you recognize the warning signs early and understand what options are available.
From Common Virus To Dangerous Mutation: What Causes FIP?
Most cats—yes, even healthy indoor ones—carry feline coronavirus (not to be confused with COVID-19). In most cases, it causes mild gastrointestinal upset or passes unnoticed. But in rare instances, the virus mutates inside the cat’s body, triggering an intense immune response. This mutated version is what leads to FIP.
FIP is not directly contagious between cats, which often surprises people. It’s the original coronavirus that spreads. Whether a cat develops FIP depends more on their immune system, genetics, stress levels, and overall health.
Two Forms, Two Very Different Journeys
One of the reasons FIP is so hard to catch early is because it shows up in two very different forms:
1. Wet (Effusive) FIP – This type causes fluid to build up in the abdomen or chest. You might notice your cat’s belly suddenly becoming bloated, or your cat struggling to breathe.
2. Dry (Non-Effusive) FIP – This form is trickier. It involves inflammation in organs like the eyes, brain, liver, or kidneys. Symptoms may include weight loss, fever, wobbliness, or behavioral changes.
Both forms are serious, and without treatment, FIP is almost always fatal. That’s why early detection and immediate care matter.
Early Signs That Shouldn’t Be Ignored
Many FIP symptoms are vague at first, which makes diagnosis difficult. Here’s what to keep an eye on:
- Persistent fever that doesn’t respond to antibiotics
- Weight loss despite a normal appetite
- Lethargy or hiding behavior
- Loss of appetite
- Trouble breathing or sudden belly swelling
- Neurological symptoms like wobbling, head tilt, or seizures
- Cloudy eyes or vision changes
If your cat is showing more than one of these signs and nothing else seems to explain it, FIP should be on the radar. At Atlas Animal Hospital, our team is skilled at navigating the diagnostic process with care and clarity, using a combination of physical exams, lab work, and imaging.
Diagnosing FIP Isn’t Straightforward—Here’s Why
There’s no single test that screams “Yes, this is FIP.” Instead, diagnosis often involves ruling out other conditions. Bloodwork may show anemia or elevated proteins, and imaging can help spot fluid buildup or enlarged organs. In some cases, analyzing the fluid from the abdomen or chest is key.
Because it’s so complex, FIP is often diagnosed based on a combination of symptoms, test results, and clinical judgment. That’s why choosing an experienced veterinary team—like the one at Atlas Animal Hospital—can make a huge difference.
Is FIP Still A Death Sentence? Not Anymore.
Just a few years ago, an FIP diagnosis felt like the end. But today, there’s real hope. Antiviral drugs—particularly GS-441524—have shown remarkable success in treating FIP, with many cats going on to live happy, healthy lives after treatment.
While these medications are not yet fully approved in some countries, they’re increasingly available through compassionate use programs and international sources. Our team can help guide you through what’s possible and what’s legal in our region.
Supportive care is also vital—hydration, nutrition, and monitoring are key to keeping your cat stable during recovery.
Be Proactive: What You Can Do As A Cat Parent
While you can’t fully prevent FIP, there are ways to reduce your cat’s risk:
- Keep stress low, especially in multi-cat households
- Maintain a clean, low-density living space
- Regular vet checkups to monitor overall health
- Isolate sick cats and avoid overcrowding in shelters or foster setups
If you’ve adopted a cat from a rescue, especially a kitten or young adult, stay vigilant during the first year. FIP most commonly strikes cats under two years of age.
If You’re Worried, We’re Here To Help
FIP can be overwhelming, especially if you’re hearing about it for the first time under difficult circumstances. Whether you’re seeing subtle symptoms or navigating a recent diagnosis, you don’t have to go through it alone.
Call Atlas Animal Hospital at 604-301-0300 to speak with our team or schedule an exam. We’re here to provide answers, explore treatment options, and support you every step of the way.
