- Dr. Liane Merritt
- Jun 26
- 7 min read
We get it—when you find cat diarrhea on your floor, your first reaction isn’t purrrty. But after checking on your pet (and cleaning up the mess), you’re probably asking yourself, “Do I need to take my cat to the emergency vet?”
In this blog, we’ll discuss causes for cat diarrhea and when you should absolutely call your local VEG ER for Pets emergency vet hospital.
When is cat diarrhea an emergency?
Cats can have an off day now and then, just like us. They may have eaten something that didn’t agree with them, reacted to a new food or medication, or have a parasitic infection. Even stress from a disruption in routine can cause a bout of diarrhea.
There are times, however, when diarrhea can be something more serious and should be treated as a medical emergency. Bring your pet to your nearest VEG for Pets if your cat experiences any of the following:
Diarrhea that lasts longer than 24-48 hours
There is blood present in the diarrhea
Diarrhea is accompanied by vomiting, fever, or lack of appetite
Your cat shows signs of dehydration (dry gums, lethargy, sunken eyes, slow skin elasticity)
Your cat is a kitten, an older cat, is pregnant, or has a pre-existing health condition, and/or has a weakened immune system
Common causes of diarrhea in cats
Here are some of the more common causes of diarrhea in cats:
Dietary issues
Garbage scavenging, transitioning to a new cat food too quickly, food allergies or intolerances, high-carb or high-fat table scraps, and (for many adult cats) milk or dairy products can cause diarrhea.
Parasites
Worms (roundworms, hookworms, whipworms, tapeworms) and single-cell parasites like Giardia, or Coccidia (most common in kittens under 6 months old) and Tritrichomonas foetus (common in young cats in multi-cat households) can trigger diarrhea in cats.
Infections
Bacterial and viral infections can happen to your cat through:
Direct exposure to an infected animal.
Environmental exposure such as ingestion of contaminated food (raw food or hunted prey like rodents, birds, or reptiles that are consumed) or contaminated water (ponds, puddles, standing water).
Shelters and multi-cat households can sometimes promote transmission.
Stress from moving to a different environment/new home can suppress a cat’s immune system, leaving them vulnerable to pathogens.
Kittens with their underdeveloped immune systems can be susceptible to infections as can older cats or cats with existing health issues.
Common bacterial infections include:
Salmonella
Clostridium
Campylobacter
Common viral infections include:
Feline Panleukopenia (FPV or Feline Parvovirus)
Feline Coronavirus (FCoV)
Feline Leukemia (FeLV) & Immunodeficiency (FIV)
While these viruses don’t attack the gut, they do hinder the immune system, making your cat more susceptible to intestinal pathogens.
Reactions to medications
Antibiotics, meds for pain relief, steroids, chemotherapy drugs and heart/asthma medications like bronchodilators can trigger diarrhea in some cats.
NOTE: Always talk to your vet about medication reactions before discontinuing their use.
Toxic ingestion
Ingestions of toxic substances can trigger diarrhea, among other symptoms, as your cat’s body processes it through their digestive tract. These include:
• Certain foods (chocolate/caffeine, onions, garlic, chives)
• Household cleaners
• Human medications or vitamins
• Toxic plants (lilies, chrysanthemums, tulips, daffodils)
Note: Ingestion of toxic substances is ALWAYS a medical emergency requiring immediate veterinary intervention, regardless if diarrhea is present.
Chronic disease
Illnesses of the gastrointestinal tract and metabolic and endocrine diseases can leave your cat susceptible to diarrhea. These include:
Chronic Inflammatory Enteropathy (CIE)
Cancers
Chronic parasitic infections
Food allergies/intolerances
Metabolic and endocrine diseases
Liver or kidney disease
Hyperthyroidism
3 things to do if your cat has diarrhea
1. Note consistency and frequency
Keep tabs on your cat’s litter box activities. If you notice your cat making frequent trips to the litter box or if the consistency of their poop changes drastically, it’s a red flag. Call your primary vet or your nearby VEG ER for Pets and one of our ER doctors will advise you on next steps.
2. Monitor duration
If your cat’s diarrhea continues for more than a day, that’s cause for concern. The longer it lasts, the higher the risk of dehydration and other complications.
3. Watch for behavioral changes and symptoms
Is your cat acting off (lethargic, not eating, etc.)? Changes like decreased appetite or hiding accompanied by diarrhea can indicate something more serious is going on. Be aware of physical symptoms like:
Cat has severe or bloody diarrhea
If you notice the diarrhea has blood in it or seems like an extreme bout, get to your nearest VEG ER for Pets immediately.
Cat is vomiting
If your cat’s diarrhea is coupled with vomiting, it’s a clear sign to seek emergency vet help ASAP.
Cat is lethargic
If your cat is overly tired or displaying other concerning symptoms, don’t wait - lethargy indicates a problem in your cat's health. Bring your cat to VEG ER for Pets at once.
Sometimes, you just know something isn’t right with your cat. Trust your gut; you know your pet better than anyone else.
Risk of ignoring your cat’s diarrhea or waiting for it to pass
It’s crucial to understand that leaving your cat’s diarrhea untreated can lead to complications. Here’s what can happen if you don’t act:
Dehydration - Dehydration in cats is serious. Even a minor loss of body fluids can result in significant issues, like kidney problems.
Worsening of underlying conditions - Sometimes, diarrhea is just the tip of the iceberg. It could be a sign of something more serious, like parasites, infections, or other underlying health issues.
Nutritional deficiencies & weight loss - If your kitty is dealing with ongoing diarrhea, they’re most likely losing essential nutrients their body needs to function properly. Over time, this can lead to weight loss and malnutrition, which can further manifest into lethargy, muscle loss and weakness, and electrolyte imbalances.
VEG ER for Pets is here for you and your cat 24/7
If your cat has diarrhea and you’re noticing any of these signs we’ve mentioned, don’t wait. Find one of our VEG ER for Pets locations and give us a call. We’re always open, even on holidays, and can offer expert advice and care tailored to your pet’s needs. The well-being of your cat is always our top priority.
Cat diarrhea: frequently asked questions
What do I do if my cat has diarrhea but seems normal?
Diarrhea isn’t “normal,” so don’t ignore it, even if your cat seems OK. Additional signs like lethargy, not eating or drinking, blood in the stool, vomiting, and the severity and frequency of the diarrhea can be indications of something more serious than a simple gastro upset.
My cat has diarrhea and is vomiting - is this an emergency?
Diarrhea and vomiting puts your cat at serious risk of dehydration, which is a medical emergency. If your cat has diarrhea and is vomiting and/or not eating, it could be an obstruction - another medical emergency. Bring your cat to your nearest VEG ER for Pets.
My cat has bloody diarrhea - should I be worried?
Bloody diarrhea can be caused by any number of factors, including parasites, gastrointestinal issues like colitis, bacterial or viral infections, toxins or dietary issues, or underlying changes in their systemic health (kidney or liver disease, etc.). A trip to the vet’s is warranted to determine the cause and subsequent treatment. Blood that is bright red indicates bleeding from the lower intestinal tract, while black or tarry stool indicates bleeding from the lower tract.
My cat has diarrhea but is still eating. Is this normal?
If your cat has diarrhea but is still eating normally and doesn’t show additional symptoms of more serious conditions (lethargy, vomiting, blood in stool) it could be a simple digestive upset. If diarrhea continues or increases over the next 24 hours or if other symptoms appear, take your cat to the vet for proper assessment.
What should I feed a cat with diarrhea?
Keep your cat’s diet bland - unseasoned boiled chicken (no bones or skins) and plain white rice are easily digestible foods for a troubled tummy. Dehydration is a concern for any bout with diarrhea, so anything you can do to encourage your cat to drink more is important.
Always have plenty of fresh water available. To encourage hydration, try adding a few drops of liquid from water-packed [not oil] tuna, or unseasoned, low-salt or no salt chicken broth. You might also try running water from a faucet or fountain, ice cubes, or shaved iced.
Will cat’s diarrhea resolve on its own?
Simple, mild diarrhea can resolve itself within 24-48 hours. Be vigilant about monitoring your cat for additional symptoms and/or diarrhea frequency and volume.
How can I treat my cat’s diarrhea at home?
A bland diet of plain boiled chicken and white rice is easy for your cat to digest. You can ask your primary care vet if adding a little canned pumpkin (not pumpkin pie filling) is okay. Since dehydration is always such a concern with diarrhea, finding ways to keep your cat hydrated is important.
Along with the tips we noted above, include some of the water you boiled the chicken in with your cat’s chicken and rice.
Note: NEVER give your cat human medication for diarrhea.
What to do if my 6 month old kitten has diarrhea? Or if my older cat has diarrhea?
Kittens, older cats, cats with pre-existing health issues, and/or cats with compromised immune systems should see a vet immediately if they have diarrhea. They are at increased risk of dehydration and electrolyte loss which can lead to additional or worsening health issues.
