Finding loose stool in the litter box is unpleasant, but the more useful question is how your cat is doing overall. A playful adult cat with one soft stool is different from a kitten with frequent watery diarrhea, a cat that is vomiting, or one that has stopped eating. Diarrhea describes a symptom; it does not identify the cause.
What can cause diarrhea in cats?
Recent diet changes, stress, intestinal parasites, infections, food-related disorders, and inflammatory intestinal disease are among the possibilities. Persistent or recurring diarrhea can also accompany conditions outside the intestines, including thyroid, kidney, or liver disease. Stool color and odor are not enough to distinguish these causes.
When you contact a veterinarian, mention your cat’s age, diet, medications, travel, access to outdoor prey, and whether other pets have similar signs. A photo of the stool or a fresh sample, if requested by the clinic, can be useful.
When diarrhea is urgent
Seek prompt in-person care if diarrhea is accompanied by repeated vomiting, weakness, collapse, marked lethargy, abdominal pain, blood or black tarry stool, inability to drink, or suspected toxin exposure. Kittens, older cats, and cats with known medical problems warrant a lower threshold for calling. A cat that is not eating also needs timely veterinary attention, because prolonged poor intake can become serious.
Contact your veterinarian if diarrhea continues beyond a day or two, recurs, or is accompanied by a change in appetite or behavior. Even when a cat looks fairly normal, ongoing fluid loss can lead to dehydration.
Checking hydration without guessing
Watch for changes in drinking, urination, activity, and appetite. Dry or tacky gums, weakness, and sunken eyes can accompany dehydration, but home checks are imperfect. Skin elasticity is particularly unreliable in some older cats. If you suspect dehydration, call a veterinarian rather than trying to replace significant losses with home treatments.
What a veterinary visit may involve
Your veterinarian may assess hydration and weight, examine the abdomen, review diet and parasite-prevention history, and recommend fecal tests, blood work, or imaging based on the clinical picture. Treatment might include fluids, parasite treatment when indicated, or a carefully chosen diet. Antibiotics and antidiarrheal drugs are not automatically appropriate.
What to avoid at home
- Do not give loperamide, bismuth products, or other human diarrhea medicines without explicit veterinary instructions.
- Do not withhold water; keep fresh water accessible.
- Avoid repeated abrupt food switches or large amounts of treats.
- Do not force-feed a nauseated, weak, or distressed cat.
- Keep the litter box clean and note frequency and appearance of stools.
Ask your veterinarian whether a short-term diet adjustment is appropriate for your cat. Cats are not small dogs, and feeding recommendations depend on age, health status, and how much they are eating.
Can a virtual veterinary visit help?
A remote veterinarian may help with triage and with preparing the information an in-person clinic needs. But persistent diarrhea, dehydration, and possible infection often require physical examination and testing. Prescription decisions must comply with applicable laws and the veterinarian-client-patient relationship. You can also read our guide to discussing cat diarrhea with a vet online.
Common questions
Does a little mucus mean something serious?
Mucus can occur with intestinal irritation, but its presence alone cannot establish a diagnosis. The duration and your cat’s overall condition matter more.
Can stress cause loose stool?
Yes, stress or abrupt routine changes may contribute, but do not assume stress is the cause of persistent or worsening diarrhea.
Should I bring a stool sample?
Ask your clinic. A recent sample in a clean, sealed container may help with parasite or other fecal testing.
Sources
Based on Cornell Feline Health Center: Diarrhea and Cornell: Hydration. Educational information only; not a substitute for veterinary examination or a claim of individual veterinary review.
This article is for general education and is not a substitute for care from your own veterinarian. Learn about The Pet Vet and our editorial policy.