Blood in My Dog's Stool, What to Do?

Our dog having any bleeding is always a cause for concern and should also mean an urgent visit to the vet. What's more, if blood loss comes with diarrhea, that's another symptom we can't ignore.

Below, we'll look at the most common causes of bloody diarrhea. We'll see that they can range in severity, and what other symptoms we should watch for.

Main causes of bloody diarrhea in dogs

There are many possible causes behind bloody diarrhea in dogs. Some are milder, others more serious. Both blood and diarrhea are warning signs, and we should pay close attention when they appear.

Diarrhea can be acute or chronic, lasting several weeks or even months, sometimes on and off. In the case of bloody diarrhea, it usually appears acutely. This blood can look fresh (large intestine) or digested and darker (small intestine).

Almost every time, it's a gastrointestinal disorder. Generally speaking, bloody diarrhea can be caused by:

• Intestinal parasites.
• Viral enteric infections such as parvovirus.
• Colitis.
• Poisoning.
• Inflammatory bowel disease.
• Diet changes or food intolerances.
• Bleeding from a foreign object.

What should I do if my dog has bloody stool?

Many vet visits involve bloody diarrhea, and it tends to be quite alarming; however, if we notice a bit of blood in a single bowel movement, and the dog isn't listless and shows no other symptoms, we can try a bland diet of boiled chicken and rice with no bones.

If bloody diarrhea happens again, or the dog shows other symptoms, don't wait any longer — call the vet. We also shouldn't wait if our dog is a puppy or already has another condition. Below, we cover things to keep in mind for the different causes of bloody diarrhea.

Causes of bloody diarrhea in puppies

A puppy with bloody diarrhea should always put us on alert. Younger dogs, especially those who haven't finished their vaccination schedule yet, are the ones at highest risk of contracting a much-feared acute infectious enteritis: parvovirus. This viral disease is characterized by causing vomiting, bloody diarrhea, listlessness, apathy, and so on.

There's also usually fever. This intense fluid loss causes dehydration in the puppy. Treatment will be symptomatic and supportive while their immune system manages to get the virus under control. If they're eating on their own, that's a good sign in this case. That said, mortality is high, which is why vaccinating puppies against it is considered essential and mandatory.

In puppies, most cases of bloody diarrhea are due to parvovirus. However, there are intestinal parasites such as Giardia sp. that occasionally cause bloody diarrhea. Quality food, a controlled environment, along with regular deworming and vaccinations, will reduce the risk of diarrhea in our puppy.

Colitis in dogs

Colitis, as the name suggests, is inflammation of the colon. There are several causes of colitis, such as inflammatory bowel disease, certain parasites, food outside their diet that didn't agree with them, foreign objects, and others.

Along with these causes described, the vet may see colitis as a symptom via X-ray. It's usually associated with fresh bloody diarrhea, since these causes make the colon prone to inflammation, allowing bacteria such as Clostridium to multiply, along with gas, and with it, blood in the stool.

Feeding-related issues in dogs

Dogs, especially younger or more curious ones, are very prone to swallowing anything they find while exploring their surroundings. This is the case, for example, of dogs who've gotten into the trash. Other times, it's us sharing food with them that can predispose them to intestinal inflammation and, with it, bloody diarrhea (for example, very fatty, heavy meals).

We don't always think it might not agree with them. It's also not unusual for us to make the mistake of suddenly switching their food or giving them low-quality diets. All these situations expose the digestive system to inflammation, with the symptoms that come with it.

Sometimes the result is bloody diarrhea. To avoid this problem, we should always keep our dog on quality food, avoiding human food as much as possible. Any change to their diet should be introduced gradually over three days.

Common conditions in older dogs

Some diseases affecting and damaging vital organs have bloody diarrhea among their symptoms. Although these are more common in older dogs, this doesn't mean they can't occur in younger ones.

For example, with kidney failure, besides symptoms like increased water intake and urination (among many others), we sometimes also find diarrhea that could be bloody, due to the damage the disease causes at the digestive level.

With liver failure, diarrhea can appear that sometimes contains blood. In every case, seeing the vet is essential. Treatment will depend on the cause behind the bloody diarrhea symptom.

When is bloody diarrhea an emergency?

Although any bleeding is always a reason to see the vet, there are times when getting the dog to the clinic needs to happen immediately. Otherwise, the risk of death is very high. Poisoning is one such example.

When we suspect our dog has ingested a dangerous substance, we should see the vet. It's very important to keep in mind that some toxins, such as certain rodenticides, cause internal bleeding and clotting problems. Symptoms can appear immediately or after hours or even days.

Other signs of poisoning are weakness, pale mucous membranes, nosebleeds, or vomiting blood. We should see the vet as soon as we discover the dog has ingested them.

Bibliography Carlson and Giffin. 2002. Manual práctico de veterinaria canina. Madrid. Editorial el Drac.