Customer Service: Contact Us Here +1 (844) 673-7287 • 9am - 5pm EST (M-F)

Black dog poop: What your dog’s dark stool means

Dog poops black or dark stool

Reviewed by: Dr. David Tittle,BVetMed, CertVA, GPCert(WVA&CPM), MRCVS

As a dog owner, you know that monitoring your furry friend’s poop is a crucial part of keeping them healthy. But what do you do if you notice that their poop is black? 

While it may seem alarming, black dog poop is not uncommon and can have several causes, ranging from harmless to serious. Why may a dog’s poop turn black? What should you do to keep your pup’s digestive system running smoothly? 

Table of contents 

Causes of black dog poop 


One of the most common reasons for black dog poop is diet. Certain foods or substances can cause changes in the color of a dog’s poop, including black stool. For example, if your dog has been eating foods containing charcoal or blood, which can occur if a dog eats raw meat or has internal bleeding in the digestive tract, they may have dark or even black poop.  


Medications or supplements can contain compounds that may also be a culprit for black dog poop. Iron supplements, for example, are known to cause dark or black stool in both humans and dogs. Bismuth subsalicylate, an active ingredient found in some anti-diarrheal medications, can also cause black poop. Additionally, certain antibiotics and pain medications may cause gastrointestinal irritation and bleeding, which can lead to black stool in dogs. 

Gastrointestinal bleeding 

Gastrointestinal bleeding can occur when there is bleeding in the upper digestive tract, such as the stomach or small intestine, or in the lower digestive tract, such as the colon. The blood that is present in the stool can cause it to appear black or tarry. Gastrointestinal bleeding can have several underlying causes, including ulcers, tumors, infections, and inflammatory bowel disease. In addition to black stool, dogs with gastrointestinal bleeding may exhibit symptoms such as vomiting, diarrhea, abdominal pain, and loss of appetite.  The blood that is present in the stool can often determine the location of gastrointestinal bleeding. For example, black, tarry, sticky feces usually indicates upper gastrointestinal bleeding, whereas fresh red blood usually implies the bleeding is from the lower gastrointestinal tract.

Parasites or infections 

Certain intestinal parasites, such as hookworms or whipworms, can cause gastrointestinal bleeding, which can lead to black stool in dogs. In addition to black poop, dogs with parasitic infections may exhibit symptoms such as diarrhea, weight loss, and anemia. Parasites are usually diagnosed through a fecal examination, and treatment typically involves administering antiparasitic medication. Additionally, practicing good hygiene, such as picking up your dog’s poop and cleaning up their living area regularly, can help prevent parasitic infections. 

Liver or kidney disease 

In some cases, black dog poop may be a symptom of more serious underlying conditions such as liver or kidney disease. These diseases can affect the dog’s ability to properly metabolize and eliminate waste products, leading to changes in the color and consistency of their stool. Dogs with liver disease may have black or tarry stools due to the presence of digested blood in the stool. Kidney disease may also lead to stools that are black and tarry, due to the presence of excess urea causing ulceration of the stomach. Other symptoms of liver or kidney disease may include lethargy, loss of appetite, vomiting, and increased thirst and urination. 

Symptoms to watch for 

In addition to black dog poop, there are several symptoms that may accompany this condition, including diarrhea, vomiting, and lethargy. Diarrhea and vomiting can lead to dehydration, which can be a serious concern in dogs, especially in young puppies or older dogs. If your dog’s black poop is accompanied by diarrhea or vomiting, it is important to ensure that they are drinking plenty of water to prevent dehydration. You may also need to adjust their diet and avoid feeding them any foods that could further irritate their digestive system.  

Lethargy or weakness can be a sign of an underlying infection or disease that may require medical attention. In general, if you notice any changes in your dog’s stool, including black or tarry stools, it is important to seek veterinary care as soon as possible. Your vet can perform a physical examination and any necessary tests to diagnose the underlying cause and develop a treatment plan to help your furry friend feel better. 


When a pet owner brings their dog to a veterinarian with black poop, the veterinarian will likely perform a thorough physical examination to determine the underlying cause of their dark stool. This exam will provide insights on fever, dehydration, abdominal pain, and abnormal masses or obstructions in the gastrointestinal tract.  

If the physical examination doesn’t provide a clear diagnosis, the veterinarian may recommend blood tests to check for underlying conditions like anemia, liver or kidney disease, or pancreatitis. Additionally, a fecal analysis can check for parasites or bacterial infections that could be causing the black poop. Occasionally, additional tests, such as X-rays or an ultrasound, can provide a better look at the dog’s gastrointestinal tract. 

Once the underlying cause is identified, the veterinarian can create a treatment plan tailored to the dog’s specific needs. It’s important to consult with a veterinarian if you notice any changes in your dog’s bowel movements, as early detection and treatment can help prevent serious health issues. 

Treating black dog stool 

The treatment for black dog poop depends on the underlying cause, which can range from minor issues like dietary changes to more serious conditions like gastrointestinal bleeding. If the cause of black poop is related to diet, the veterinarian may recommend switching to a different brand of dog food or adding fiber to the dog’s diet. In cases where parasites or bacterial infections are present, the veterinarian may prescribe antibiotics or other medications to clear up the infection. 

If the underlying cause is more serious, such as gastrointestinal bleeding, the veterinarian will want to start gastrointestinal protectant (anti-ulcer) drugs, and may need to hospitalize the dog and provide supportive care, such as fluid therapy and blood transfusions. In some cases, surgery may be necessary to remove an obstruction or repair damage to the gastrointestinal tract. 


As a responsible pet owner, it’s essential to keep an eye on your dog’s poop to ensure that they are healthy. To prevent black dog poop, there are a few things you can do. Firstly, make sure your dog is on a healthy and balanced diet that is free from any potential allergens. This can help prevent digestive issues and keep their stool healthy. Additionally, provide plenty of clean water to keep your dog hydrated, which can help prevent constipation and other digestive problems. Regular parasite control treatments are essential. Finally, if you notice any unusual changes in your dog’s poop, including black color, it’s important to consult your veterinarian for a checkup to rule out any underlying health concerns. 


Your dog’s black poop is not something to be taken lightly, as it can be an indication of serious health issues. As a responsible pet owner, it’s crucial to keep a close eye on your dog’s stool and take necessary precautions to prevent any potential health problems. By providing your dog with a healthy and balanced diet, plenty of clean water, and regular checkups with your veterinarian, you can help keep your furry friend healthy and happy.