What to Do: Blood in Dog's Stool
- VEG
- Oct 30, 2024
- 6 min read
Updated: 6 days ago
While seeing blood in your dog’s stool can be alarming, it can have a range of causes, from simple, short-lived digestive issues to more serious health concerns. Only a professional evaluation can provide an accurate diagnosis. Visit your nearest VEG ER for Pets if you see your dog pooping blood or notice traces of blood in your dog's poo.
Noting any additional symptoms your dog may be experiencing to help our vet determine how critical your dog’s condition may be. Blood in your dog’s stool may be accompanied by the following signs and symptoms:
Restlessness
Panting
Straining to relieve him/herself
Dog Health Tip: Dehydration is a real concern if your dog is pooping blood and also vomiting, has diarrhea, and/or isn’t eating or drinking. This should be regarded as an emergency regardless of the root cause.
Why is My Dog Pooping Blood?
There are many reasons why blood may appear in a dog's stool. It's also concerning if you see that your dog is pooping blood. The color of the blood your dog is pooping can give us more information.
How blood in dog stool appears can vary greatly in amount, form and color. Blood in stool can appear as:
A range in color from bright red to dark red or black
Some specs of blood in otherwise normal formed stool
A coating of blood and mucous surrounding formed stool
Loose stool/diarrhea mixed with blood
Little to no stool, just blood and/or mucous
Dog Health Tip: It’s always a good idea to be familiar with what a “normal” poop looks like for your pup, since some dogs naturally have more solidly formed feces than others. Changes in stool formation and frequency (with or without blood) can be indicative of health changes.
Potential Causes of Red Blood in Dog Stool
Red or bright red blood in stool (Hematochezia) indicates that the blood is coming from the lower part of your dog’s digestive tract, such as the lower colon, rectum or anus. This can be due from a range of causes, from a change in food, the broad “ate something they shouldn’t have,” to parasitic infections or lower bowel disease. Common reasons for red blood appearing in your pup’s stool can include:
Dietary changes
Switching to a new food too quickly can affect some dogs’ digestive system more than others.
Medications
Like people, dogs have different tolerances to medications, plus some medications must be given with food to avoid stomach upset.
Ingesting irritating objects
Sticks, pebbles, toys, shoes - there’s a long list of things your pup shouldn’t eat (but may anyway!).
Certain foods
Beets, berries, and commercial foods or treats with red dyes can make your dog’s poop appear red, without containing any actual blood.
Full or impacted anal glands
Many dogs need to have their anal glands manually expressed (this is often done by a vet or experienced groomer). If you notice your dog fussing/licking his anus or “scooting,” share this observation with your vet.
Hemorrhoids
Yes, dogs can get hemorrhoids. If your vet diagnoses your dog with hemorrhoids, he/she may advise you to up both the water and fiber intake of your dog’s diet and/or prescribe a stool softener to make defecation easier for your pup.
Parasitic/bacterial/viral illnesses
Hookworms, tapeworms, roundworms, whipworms, giardia, coccidia, salmonella, parvovirus are more serious causes for red blood appearing in your dog’s stools, some - like parvo and salmonella - with potentially lethal results. These are health emergencies requiring immediate care.
Lower bowel diseases
Colitis and Inflammatory Bowel Disease (IBD) are also some of the more serious causes for the appearance of red blood in your dog’s stool, and should be treated as such.

Potential Causes of Black Blood in Dog Stool
Black, tarry-looking blood in your dog’s stool (Melena) typically comes from somewhere further up in the digestive tract, usually near the stomach or small intestine. Black blood can be more difficult to detect since the type of food your dog eats can affect the color of its stool. Foods that primarily contain red meats or organ meats, are high in iron, or contain charcoal, can result in naturally darker stools. Dark, tarry-looking blood can often be a sign of a serious problem that needs to be handled by your vet immediately.
Quick action offers the chance for some of these problems to be successfully treated when caught early, so don’t delay care. Reasons for your dog’s poop to appear dark or include dark, tarry-looking blood can include:
Diet/medications
Some of the more benign causes of black blood in stool (which is indicative of digested blood) can include ingesting raw meat, (whether fed intentionally or as a result of your dog catching and eating mice, rabbits, birds, etc.), treats or food with activated charcoal, certain medications like iron supplements, NSAIDs and corticosteroids, and bismuth subsalicylate (Pepto-Bismol).
Pancreatitis or Inflammatory Bowel Disease
In some cases, dogs may have black stool from pancreatitis or inflammatory bowel disease. Both of these conditions are very treatable in dogs, and they can be managed over the course of your dog’s life by following your vet’s guidelines. These conditions do not have to be fatal for your dog, especially with quick and regular vet treatment.
Metabolic diseases
Hypothyroidism and hyperadrenocorticism can often cause dark, loose stools in dogs. Hypothyroidism (low thyroid) slows down metabolism which can result in a number of gastrointestinal issues, while hyperadrenocorticism (Cushing’s Disease) is a result of high cortisone levels due to an overactivity of the adrenal gland. Both are easily diagnosed and treatable, although not curable.
Parasitic, bacterial, and viral infections
Similarly to the appearance of red blood in stool, parasitic, bacterial and viral infections can also cause dark blood in stool. The difference is the location of the infection in the digestive tract.
Blood clotting disorders
Genetic diseases like von Willebrand’s Disease (vWD) is the most common blood-clotting disorder in dogs, due to an inherent deficiency of a specific protein needed for blood platelet formation.
Rodenticide poisoning
A dog may either consume rodent bait first-hand or ingest it by eating a mouse, rat or other small animal that ate the anticoagulant bait. The bait works by inhibiting the activity of vitamin K1, which is essential for blood clotting. Along with dark, loose stool, dogs may also produce bloody vomit and bleed from any orifice. Dogs may not exhibit symptoms for a day or 2 after ingestion. This is a life-threatening emergency that requires immediate hospital care.
Renal disease
Dark, tarry stools are not uncommon in dogs with kidney disease. This happens when the kidneys can no longer filter waste products from the blood. Toxins such as ammonia build up in the blood and can damage/ulcerate intestinal and stomach linings. Close management of kidney disease with your vet is essential.
Tumors in the digestive system
Dogs may develop black stool if they have tumors in their digestive system. This can sometimes be a symptom of cancer in dogs as well, but intestinal and stomach cancers are relatively rare in dogs, occurring more frequently in older dogs (9+ years of age). According to the National Canine Cancer Foundation, gastric cancers in dogs account for less than 1% of all malignant tumors.
Is Blood in My Dog's Stool and Emergency?
Even a small amount of blood in the stool of a puppy or young dog should be regarded as an emergency and requires an immediate trip to an emergency vet hospital, like VEG ER for Pets, since this could indicate parvovirus. This is a very serious and potentially fatal illness that must be treated by a professional right away.
One of our highly skilled veterinarians at VEG will offer advice on how to proceed with caring for your pet once they’ve diagnosed the cause of the blood in your dog’s stool and will provide the treatment your pet needs.

Treatments for Blood in Dog Stool - Proper Diagnosis is Key
Depending on the cause, there may be a variety of treatments you can expect when dealing with blood in your dog’s stool. However, before a treatment plan can be determined, your pet must be seen one of our emergency trained veterinarians as soon as possible for an accurate diagnosis. Some of the tests our veterinarian might conduct to find out why your dog has blood in their stool include, but are not limited to:
Rectal exam
X-rays
Ultrasounds
Endoscopies/Colonoscopies
Blood work
Fecal tests
Urine tests
What To Do If There Is Blood In My Dog’s Stool
When your dog has blood in his/her stool, don’t delay in contacting our vet by phone or bringing your dog into your local VEG hospital. At VEG ER for Pets, you will always speak with a compassionate emergency vet who is ready to help you with treating any illness your pet may be experiencing.