Health Topics  >  Digestive  >  Diarrhea

How do you know if diarrhea is a sign of a serious problem or an emergency?

If any of the following symptoms or circumstances apply, it’s a sign of a more serious situation and may be an emergency:

  • Your dog’s diarrhea does not improve within 24 hours
  • If the situation gets worse and it becomes more frequent or voluminous
  • If you see signs of blood (red) or digested blood (black and tarry) in your dog’s stool (a little bit of blood may not be an emergency, but it’s definitely a cause for concern) 
  • Other symptoms including vomiting, abdominal pain or extreme lethargy
  • You suspect your dog has ingested a toxin or something poisonous


Diarrhea can quickly cause dehydration, so it’s important to monitor your dog’s water intake and add some water in their food to increase intake. Even if your dog is drinking water, they may not be able to drink enough to compensate for what they are losing in the loose stool. 

If they become lethargic or weak, this is a sign your dog needs veterinary attention. Never withhold food or water from your dog, even if they have diarrhea. Smaller, more frequent meals with added water can be helpful to compensate for the dehydration.