Cat or Dog Diarrhea: When Is It Okay and When Should You Worry?

Diarrhea is common in pets, often after a change of food or eating something unusual. Most cases are mild, but repeated or bloody diarrhea can quickly leave your pet weak and dehydrated.

When is it okay to monitor?

If your pet has loose stool once or twice but stays active, keeps eating and drinking, and isn't vomiting, you can usually watch them at home.

Note down these details

• Frequency: How many times, and since when?

• Stool: Watery, mucus, or blood? Take a photo for your vet.

• Food: Any change of food, new treats, or a chance they swallowed something?

• Energy: Still active, or very weak?

• Other symptoms: Any vomiting or loss of appetite?

What you can do now

• Make sure your pet keeps drinking.

• Don't give human anti-diarrhea medicine.

• Keep the stool photo and your notes for the vet.

See a vet right away if

• The diarrhea is bloody, or very watery and frequent

• It comes with vomiting, especially more than 3 times in a few hours

• Your pet is very weak, won't eat, or won't drink

• The belly looks bloated or painful

• They may have swallowed a toxin or foreign object

• It doesn't improve after monitoring

Testing at Modernvet

Modernvet's vets can examine your pet and, if needed, run an in-clinic stool test with results in 15–60 minutes to help find the cause. Book an appointment in the Modernvet app, or message our team on WhatsApp with a stool photo if you're unsure how urgent it is.