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Why Is There Blood in My Dog's Stool?

There are a lot of things that can cause blood in a dog’s stool.

If you've had dogs for a while, chances are you've had the experience of seeing blood in their stool. Some causes of blood in a dog's stool are simple and not too concerning but others can be quite serious, so it's good to have an idea of what to look for.

Causes of Blood in a Dog's Stool

Blood in the stool can be caused by anything that happens in the digestive tract from the mouth to the anus and can include:

Diagnosing the Cause of Blood in a Dog's Stool

If there is blood in your dog's stool, there are some other clues that may help narrow down what's causing it. These include:

  • Whether the blood is bright red (hematochezia) or black and tarry (melena). Bright red blood comes from the end of the digestive tract (colon, anus, or rectum) and black blood comes from the beginning (stomach or small intestine).
  • Whether the blood is accompanied by diarrhea.
  • Whether the dog has other signs of illness concurrently, such as weakness, vomiting, fever, inappetence, pinpoint red spots on the skin or in the whites of the eyes, lethargy etc.

When a veterinarian evaluates your dog for bloody stool, he or she will ask you questions about its duration and any other signs of illness you have noticed. Then, the doctor will do a thorough physical examination to look for other signs of illness.

The doctor will most likely run a fecal test to look for intestinal parasites and may run other tests too, such as blood work, x-rays, ultrasound, etc.

Treatment of Blood in a Dog's Stool

The treatment of blood in a dog's stool depends on the cause. Once your veterinarian has determined what's causing the blood, he or she will be able to develop a treatment plan and give you a prognosis.

Is Blood in My Dog's Stool an Emergency?

If you notice blood in your dog's stool and it is accompanied by other signs of illness, such as collapse, lethargy, or vomiting, you should see a veterinarian right away. If there are no other signs of illness, it is a good idea to monitor the stool to see if the blood is consistent. If it is, collect a small sample to take to the vet and make an appointment when it's convenient.

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