Dog pooping blood or bloody diarrhea
Blood in a dog’s stool can show up as bright red streaks or drops, jelly-like bloody diarrhea, or black, tarry stool. A little bright red blood in a dog that is otherwise eating and acting normally often comes from irritation of the lower bowel, but you should still call your vet right away. Large amounts of blood, jelly-like bloody diarrhea, black stool, vomiting, weakness, pale gums, a puppy, or possible rat poison need a vet now.
General health information, not a diagnosis. If you are worried about your pet, contact a vet.
How urgent is it?
Go down the list and stop at the first row that matches your pet.
See a vet now
- Passes a large amount of blood, or bloody diarrhea that looks like jelly or raspberry jam
- Black, tarry stool, or stool that looks dark red to black when you wipe a little on a white paper towel
- Is also vomiting, or has stopped eating or drinking
- Weak, very tired, wobbly or collapsed, has pale or white gums, has a fever, or the belly seems painful
- Is a puppy or is not fully vaccinated, and has any blood in the stool or diarrhea, especially with vomiting, tiredness or not eating
- May have eaten rat or mouse poison, even several days ago, or another toxic substance, or swallowed an object such as a bone, stick or toy, even if your dog still seems fine
- Bleeding or bruising elsewhere (nose, mouth, gums or skin), blood in the urine, a swollen belly, or trouble breathing
- Has bloody diarrhea again and again within a few hours, or seems dehydrated
See a vet within 24 hours
- A streak or a few drops of bright red blood, or a little blood with mucus, on stool that is otherwise formed, while your dog is eating, drinking and acting normally: call your vet right away, and they will tell you how soon to bring your dog in
- Strains to poop, goes often and passes small amounts of soft stool with mucus, with or without a little blood, but is otherwise well
- Diarrhea has lasted more than two days, even if your dog seems fine, or small amounts of blood keep showing up on and off
- Blood or mucus in the stool keeps coming back over weeks, or your dog is losing weight
Watch at home
- A vet has already checked a small amount of blood, your dog is eating and acting normally, and the stool is getting back to normal: keep watching and call again if blood returns or new signs appear
Not sure which row fits?
Describe your pet’s symptoms and get a free urgency check in about a minute.
Check my pet’s symptomsCommon causes
| Cause | What you may notice | Usual urgency |
|---|---|---|
| Eating something it shouldn’t, or a sudden change of food | Soft stool with a little red blood after getting into the trash, eating spoiled food or sticks, or a quick switch of food | Within 24 h |
| Inflammation of the large intestine (colitis), including stress-related colitis | Small, frequent soft stools with mucus, straining, and a little bright red blood near the end; often linked to stress | Within 24 h |
| Intestinal parasites (whipworms, hookworms, Giardia) | Diarrhea with fresh blood or mucus, or dark, tarry stool; in puppies, heavy hookworm infection can cause serious blood loss | Within 24 h |
| Long-term bowel conditions (for example inflammatory bowel disease, food allergy, tumors) | Blood or mucus in the stool that comes and goes over weeks or months | Within 24 h |
| Acute hemorrhagic diarrhea syndrome (formerly called hemorrhagic gastroenteritis) | Sudden, large amounts of bloody, jelly-like diarrhea that looks like raspberry jam, often with vomiting and lethargy; more common in small and toy breeds | Now |
| Parvovirus | Puppies or unvaccinated dogs: tiredness, poor appetite and vomiting, then diarrhea that may contain blood and mucus | Now |
| Rat poison (anticoagulant type) or other toxins | Bloody or dark, tarry stool, pale gums, weakness, bruising; signs often start 3 to 7 days after the poison was eaten | Now |
| Swallowed object, blocked bowel or telescoping of the intestine | Vomiting, belly pain, not eating, small amounts of bloody diarrhea; telescoping of the intestine is more common in young dogs | Now |
| Bleeding in the stomach or small intestine (for example an ulcer) | Black, tarry stool, vomit with blood, pale gums | Now |
What you can do at home
- Keep fresh water available at all times, and take your dog outside often.
- Take a photo of the stool, and collect a fresh sample in a clean container or bag to take to the vet.
- If you are not sure whether dark stool contains blood, wipe a little on a white paper towel. Dark red or black suggests digested blood and needs a vet now. Organ meat and dark meats such as beef or venison can also make stool darker, so if the stool looks darker than usual and you are not sure why, call your vet.
- Until the stool is back to normal, skip treats, rich food and table scraps. If you change food later, switch gradually over one to two weeks.
What not to do
- Do not take water away, unless a vet tells you to.
- Do not give human medicines or stomach remedies unless a vet tells you to.
- Do not wait for signs to appear if your dog may have eaten rat or mouse poison. Signs often show up only 3 to 7 days later. Call a vet right away.
- Do not wait for jelly-like bloody diarrhea with vomiting to settle on its own. Dogs can go into shock from fluid loss before they look dehydrated.
- Do not take a puppy or unvaccinated dog with bloody diarrhea to dog parks or near other dogs, and call the clinic before you arrive.
What to tell the vet
- When you first saw blood, how many times it has happened, and whether the stool was formed, soft or watery
- What it looked like: red streaks, drops of red blood at the end, mucus, jelly-like diarrhea, or black, tarry stool (show the photo or bring the sample)
- Anything your dog may have eaten: trash, spoiled food, bones, sticks, toys, people food, rat or mouse poison, or medicines
- Other signs: vomiting, appetite, energy, gum color, straining, weight change
- Vaccinations and deworming, any recent change of food, and any recent stress
Questions owners ask
Why is my dog pooping blood but acting normal?
A little bright red blood, often near the end of a bowel movement and sometimes with mucus or straining, usually comes from the lower part of the bowel. Stress, a change of food, spoiled food and intestinal parasites are among the common causes. Many of these cases settle quickly; with stress-related colitis, for example, signs typically clear up within three to five days. Still call your vet right away, because only an exam and a stool test can tell the causes apart, and go now if the blood increases, the stool turns black or jelly-like, or your dog starts vomiting or seems tired.
What does bright red blood vs black stool in dog poop mean?
Bright red blood usually comes from the lower bowel, such as the colon or rectum, and is not always a sign of a life-threatening illness. Black, tarry stool contains digested blood and points to bleeding higher up, such as in the stomach or small intestine, so it needs a vet now. To check, wipe a little stool on a white paper towel: dark red or black suggests blood. Organ meat and dark meats such as beef or venison can also make stool darker, so if the stool looks darker than usual and you are not sure why, call your vet.
Is bloody diarrhea in dogs an emergency? Can a dog die from it?
Sudden, large amounts of bloody diarrhea that look like jelly or raspberry jam are an emergency, especially with vomiting. Dogs can lose so much fluid that they go into shock before they look dehydrated, and small and toy breeds are affected more often. With prompt hospital care most dogs recover: in a study of 237 dogs hospitalized with suspected sudden bloody diarrhea of this kind, 96% went home. Without treatment, the risk of death can be high.
Why is there blood and mucus in my dog’s poop?
Mucus, a jelly-like coating, with a little fresh blood, small frequent stools and straining are typical of inflammation of the large intestine (colitis). Stress, a change of food, infections and parasites such as whipworms or Giardia are common causes, and most dogs recover quickly with treatment. A large amount of red, jelly-like diarrhea that looks like raspberry jam is different and needs a vet now, as does blood and mucus in a puppy’s stool, which can be a sign of parvovirus. For an adult dog that is otherwise well, call your vet right away.
My puppy has blood in its stool. What should I do?
Take your puppy to a vet now. Parvovirus mostly affects puppies between 6 weeks and 6 months old that are not fully vaccinated: it starts with tiredness, poor appetite and vomiting, then comes diarrhea that may contain blood and mucus, and it can get worse quickly. Most puppies do not survive parvovirus without treatment. Hookworms can also cause severe blood loss in young puppies, which is often fatal. Call the clinic before you arrive so the staff can keep your puppy away from other dogs.
Related symptoms
Sources
- Disorders of the Stomach and Intestines in Dogs (Pet Owner Version), Merck Veterinary Manual
- Acute Hemorrhagic Diarrhea Syndrome in Dogs (Professional Version), Merck Veterinary Manual
- Gastrointestinal Parasites of Dogs (Pet Owner Version), Merck Veterinary Manual
- Acute Hemorrhagic Diarrhea Syndrome in Dogs (Hemorrhagic Gastroenteritis), VCA Animal Hospitals
- Colitis in Dogs, VCA Animal Hospitals
- Anticoagulant Rodenticide Poisoning in Dogs, VCA Animal Hospitals
- Diarrhea, Cornell Richard P. Riney Canine Health Center
- Parvovirus: Transmission to Treatment, Cornell Richard P. Riney Canine Health Center
- A Retrospective Study of 237 Dogs Hospitalized with Suspected Acute Hemorrhagic Diarrhea Syndrome: Disease Severity, Treatment, and Outcome, Journal of Veterinary Internal Medicine, 2021
- What to Do If You Find Blood in Your Dog’s Stool, American Kennel Club
Last reviewed October 25, 2026