One of the less pleasant things about being a pet parent is dealing with dog poop. While we may hate having to pick it up, keeping an eye on your dog’s poop is a good way to monitor their health. 

In general, dog poop should be firm and dark brown in color. However, every dog’s stool color and consistency will vary slightly. That is why it is good to know what normal looks like for your dog. 

So what does it mean when you see black dog poop? Keep reading for the most common causes of black poop in dogs and when you should be alarmed. 

Black Dog Poop: Deciphering Color and Consistency 

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Black dog poop can be a sign of a very serious, or even life-threatening illness. But not all poop that appears black may be abnormal. When looking at your dog’s poop, it’s important to take note of both the stool’s consistency and color.

Unless there is an obvious cause for your dog’s black poop, you should contact your veterinarian. Knowing the consistency of your dog’s stool–i.e. hard, crumbly, liquid, soft and sticky, etc.—can help your veterinarian to determine how urgently your dog should be examined, if at all. 

It is also helpful to take a picture of your dog’s abnormal poop so that you can show it to your veterinarian. 

Why Is My Dog’s Poop Black? 

Black dog poop could be caused by:

• Internal bleeding
• What your dog eats
• Medications your dog takes

Internal Bleeding

The biggest concern with black dog poop is digested blood coming from somewhere in the body. 

If your dog’s stool is black and tarry or sticky, take them to the vet right away as this is a serious symptom called melena. Bleeding anywhere in the mouth, nose, esophagus, stomach or small intestines can cause melena. Stomach ulcers are a common cause of this symptom. 

Dogs may develop ulcers as a side effect of taking certain medications, such as non-steroidal anti-inflammatory drugs (e.g. carprofen, meloxicam, grapiprant) or steroids (e.g prednisone, prednisolone). Certain bacterial infections and parasites can also lead to bleeding ulcers. Other signs of stomach ulcers include vomit that contains blood or looks like coffee grounds, decreased appetite, and decreased energy levels. 

Black dog poop may also result from bleeding tumors in the stomach, small intestines, esophagus, nose, or mouth. Rat poison ingestion is another cause of bleeding that can lead to black tarry stools. If you suspect your dog has ingested it, go to your veterinarian right away, as this can be fatal. 

Other causes of black stools related to bleeding include: 

• Bleeding disorders (e.g., Von Willebrand’s Disease, immune mediated thrombocytopenia)
• Foreign bodies or objects located in the gastrointestinal tract, causing a blockage 
• Trauma that leads to internal bleeding (e.g. being hit by a car or falling down the stairs) 
• Parvovirus, a severe, highly contagious viral condition that causes bloody diarrhea

Diet

If your dog’s poop is black but normal in consistency—especially if your dog is acting normal—look to your dog’s diet. Does your dog like to eat dirt or compost? These both could cause your dog’s poop to turn black. While this may not cause any immediate harm, eating soil can cause distress to your dog’s digestive tract (gastritis), and/or lead to intestinal parasites.

Feeding your dog dark foods, foods with black food coloring, or bloody raw meats can also turn your dog’s poop black. Feeding raw meats is not recommended due to risk of disease transmission both to the pet and the pet parents.

Medications and Supplements

In addition, iron supplements, Pepto Bismol (bismuth subsalicylate), other diarrhea medications can lead to black colored stools in dogs as they pass through the digestive system. 

Another medication that is sure to cause your dog’s poop to turn black is activated charcoal. Activated charcoal is usually administered by veterinarians when dogs have eaten something potentially toxic. The activated charcoal helps to bind to the toxins and prevents their absorption in the body.  

Why Does Dog Poop Turn Black in the Sun? 

Your dog’s poop may look normal when it is fresh but then you may notice that it turns black if left out in the sun. This is a normal change and is not a cause for concern. The cause for this color change isn’t well known. When checking your dog’s poop for color, consistency, and abnormalities, look at a fresh sample. 

What to Do If Your Dog’s Poop Is Black? 

If your dog’s poop is black for the first time but is otherwise normal and your dog is not having any other abnormal symptoms, monitor your dog closely. If the poop later returns to a normal color, there’s likely no reason for concern.

However, if your dog’s dark stool persists for several days, get them checked out by your veterinarian who can prescribe the proper treatment for black dog poop. Be sure to bring in a stool sample with you to your appointment. 

If your dog has black stool that’s soft or liquid—especially if your dog has other abnormal symptoms like lethargy, weakness, vomiting, bruising, or pale gums—take them into your regular veterinarian or an emergency veterinary hospital immediately. 

Your vet may recommend blood work, X-rays, abdominal ultrasound, fecal testing or other tests to determine the cause. Since black stool is often due to bleeding somewhere in the body, timely diagnosis and proper treatment is critical.

Veterinary care for cases of black poop in dogs can get costly, especially if your dog requires emergency care. In these situations, a pet health insurance policy, like those offered by Lemonade, can help pet parents defray the cost of treatment. Lemonade’s basic pet insurance accident and illness plan covers many of the diagnostic tests your veterinarian may recommend, as well as treatment options.

Frequently Asked Questions

Why is my dog’s poop black?

Your dog’s dark, black stool is usually caused by one of three things: internal bleeding, diet, or medications. If you are concerned about your dog’s black poop—especially if it accompanies other symptoms like lethargy, pale gums, or weakness—contact your veterinarian immediately. Black dog poop can sometimes point to serious conditions.

How do you treat black poop in dogs?

The treatment for black poop in dogs depends on its cause. In some cases, certain medications like Pepto Bismol may be the culprit and your dog’s poop will return to normal shortly after the last dose. But in other cases, the black stool may be caused by more serious conditions like internal bleeding. Your veterinarian will be able to give your proper diagnosis as well as an appropriate treatment plan.

Can blueberries cause black poop in dogs?

If your dog eats a large quantity of blueberries, it can make their stool appear black or brown with dark spots. Blueberries are a healthy treat for dogs but, as with any treat, they should be given in moderation.