Acute Diarrhea in Cats

  • Author

  • Acute diarrhea is the sudden onset of loose or watery stools lasting up to 14 days. Cats with diarrhea may pass more than the usual amount of feces, defecate more frequently, stools may start solid and turn watery.


    • Dietary indiscretion such as eating garbage, spoiled food or non-food items
    • Bacterial infection such as salmonella, campylobacter, e-Coli and tularemia
    • Protozoal infections caused by giardia, cryptosporidium,
    • Viral infections including rotavirus, panleukopenia, feline enteric coronavirus
    • Parasitic infections such as roundworms, particularly in kittens
    • Poisonings such as Ibuprofen, zinc, antifreeze, chocolate and other
    • Sudden change in diet
    • Certain medications such as antibiotics, antacids, chemotherapy drugs
    • Intestinal blockage
    • Intussusception (telescoping of the intestines)
    • Acute liver or kidney disease

    Secondary symptoms

    • Vomiting
    • Anorexia (loss of appetite)
    • Lethargy
    • Blood and mucus in the diarrhea
    • Foul-smelling diarrhea
    • Increased thirst due to dehydration
    • Increased urgency to defecate and defecating outside the litter tray
    • Fever
    • Pain when touched
    • Hunched over appearance

    Should I take a cat with diarrhea to the veterinarian?

    If your cat is eating, still active and appears to be otherwise well, a wait and see approach may be safe for 24-48 hours.

    If however your cat is experiencing other symptoms, such as those listed above, or you suspect he has ingested poison, your cat will need to be seen by a veterinarian.

    Home treatment

    • Feed a bland diet to rest the gastrointestinal tract. Ensure the cat has an adequate supply of clean, fresh drinking water as diarrhea can lead to fluid loss and dehydration.
    • Boiled or canned (unsweetened) pumpkin can help to bulk up the stools.
    • Mildly dehydrated cats can have non-flavoured electrolyte replacements such as Pedialyte. Signs of dehydration include dry and tacky gums, sunken eyes, poor skin elasticity and lethargy.
    • Lactobacillus is a type of friendly bacteria that resides in the intestinal tract of mammals. These bacteria protect the body against harmful strains of bacteria which can cause disease. This can be of help to cats with diarrhea, especially if they have been or are on a course of antibiotics which can impact healthy strains of bacteria in the GI tract.


    Do not administer human medications to your cat unless your veterinarian has specifically told you to do so. Cats are unable to process medications commonly used to treat diarrhea in humans.


    The veterinarian will perform a complete physical examination of your cat and obtain a medical history from you. If possible, bring along a fresh stool sample for your veterinarian to examine.


    • How long your cat has had diarrhea?
    • Does the diarrhea contain blood or mucus?
    • Have you noticed any other symptoms?
    • What food has the cat eaten recently?
    • Is the cat on any medications or supplements?

    The type of diarrhea may help to narrow down the veterinarian’s index of suspicion.

    • Bloody diarrhea (known as dysentery) may be suggestive of infection or inflammation.
    • Small increase in bowel movements with a large increase in the volume of feces passed indicate the small bowel is involved.
    • Large increase in the frequency of bowel movements and the presence of mucus are indicative of large bowel involvement.
    Small intestine diarrhea: Volume is increased, frequency 2-3 times normal, no mucus, urgency may be normal to mildly increased. [2]Large intestine diarrhea: Volume is normal to decreased, mucous and blood may be present, the urgency is increased, and frequency is more than five times normal. [3]

    Diagnostic workup:

    • Baseline tests include biochemical profile, complete blood count, and urinalysis to evaluate organ function and look for signs of infection.
    • X-ray or ultrasound to evaluate the organs and look for blockages.
    • Fecal studies for parasites, cysts, and eggs.

    Medical treatment

    The goal of treatment is to address the underlying cause and manage symptoms. This may include the following:

    • Fluid therapy to correct electrolyte imbalances and treat dehydration.
    • Food may be withheld for 24 hours to rest the intestines after this time a bland diet will be given

    Specific therapies:

    • Antibiotics for bacterial infection.
    • Surgery to remove foreign bodies, blockages or telescoping of the intestines.
    • Pump the stomach (gastric lavage) or induce vomiting for cats who have ingested poisons. Administer activated charcoal to prevent further absorption of the toxins.
    • Worming medication to treat roundworms.
    • Supportive care and where appropriate, antibiotics to help cats with protozoal infections.
    • Reduced protein and phosphorous diets for cats with kidney failure as well as addressing the specific cause.

    Home care

    Follow the veterinarian’s instructions and administer all medications as prescribed.

    Cats can be quite sensitive to sudden changes in diet, so if you plan to switch types of food, do so gradually and over a few days.

    If there is no improvement in your cat’s health, or if he becomes worse, seek veterinary attention immediately.

    Some cats will eat anything, including garbage and non-food items. Always dispose of food in the outside trash, avoid feeding human foods to your cat and keep all medications and toxins away from cats.


    • Julia Wilson, 'Cat World' Founder

      Julia Wilson is the founder of Cat-World, and has researched and written over 1,000 articles about cats. She is a cat expert with over 20 years of experience writing about a wide range of cat topics, with a special interest in cat health, welfare and preventative care. Julia lives in Sydney with her family, four cats and two dogs. Full author bio