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15 Causes of Mucus in a Dog's Stool

Adrienne is a certified dog trainer and former veterinarian assistant who partners with some of the best veterinarians worldwide.

It's not uncommon to find mucus in your dog's stool, and some of the causes are benign. Learn more about why this occurs and when you should be concerned.

It's not uncommon to find mucus in your dog's stool, and some of the causes are benign. Learn more about why this occurs and when you should be concerned.

Why Is There Mucus in Your Dog's Stool?

When inspecting your dog's poop, were you surprised to see mucus or something that looked like jelly? The presence of mucus is actually very normal. It's common to see a little bit of a slimy, jelly-like substance in your dog's stool. Glands in the intestinal tract naturally produce mucus to help keep the colon lubricated and moist to help the stools pass along. However, excessive mucus accompanied by blood in the stool, diarrhea, vomiting and/or other symptoms is a cause for concern.

It's always a good idea to inspect a dog's stool to see if there is anything unusual or alarming in it. Your dog's poop can tell you many things, such as what he ate, if he has parasites, if he's stressed out or if he's suffering from some form of digestive disorder. If you find mucus in your dog's stool, you may be wondering where it's coming from and what causes it. In the next paragraphs, we will learn more about it.

When Does Mucus Become a Concern?

  • When there is an excessive amount.
  • When blood is present.
  • When there is vomiting, diarrhea, lethargy and/or loss of appetite.

What Should Mucus Normally Look Like?

Normal mucus often looks like a clear jelly-like substance mixed within the stool. Sometimes, it may envelop the stool like a sausage casing. In some cases, the mucus may also appear white. If you make it a habit to routinely inspect your dog's stools, you'll quickly note when something looks off.

Why Is There Blood in My Dog's Stool?

If your dog is pooping blood but acting normal, then it is likely caused by a sudden change in your dog's diet, stress, food intolerance or dietary indiscretion.

Other serious causes of blood in dog stool include parvovirus, hemorrhagic gastroenteritis and intestinal parasites, which must be diagnosed by a veterinarian.

Call a vet immediately if you see blood along with symptoms of vomiting, chronic diarrhea, dehydration and/or lethargy.

What the Color Indicates

  • If the blood is fresh and bright red, it is derived from the colon or rectum.
  • If you see tarry stool, then the cause likely originates in the upper small intestine.

15 Causes of Mucus in Dog Poop

  1. Stress
  2. Dietary Indiscretion
  3. Food Intolerances
  4. Intoxication
  5. Diet Changes
  6. Inflammatory Bowel Disease (IBD)
  7. Crohn's Disease
  8. Colitis
  9. Presence of Intestinal Parasites/Protozoans
  10. Fungal Infection
  11. Small Intestinal Bacterial Overgrowth (SIBO)
  12. Clostridial Enterotoxicosis
  13. Parvovirus
  14. Ingesting Foreign Objects
  15. Polyps and Tumors of the Intestinal Lining

What Does It Mean If There Is Mucus in Dog Stool?

An increase in mucus is often a symptom of irritable bowel syndrome (IBS), which is an irritation and possible inflammation of the colon or large intestine. When irritated, the intestinal tract decides to create an extra layer of protective mucus lining. Dogs with irritable bowel syndrome will have the urge to defecate frequently and will pass semi-formed feces or runny stool with small amounts of bright, red blood at the end and/or excessive mucus. Following are some potential causes of irritable bowel syndrome.

1. Stress

Believe it or not, a dog's mental and emotional state could have a great impact on his bowel movement. Like humans, dogs under stress or anxiety will have diarrhea, which may include large amounts of mucus and some blood. Other symptoms include having the urge to go frequently or straining when defecating.

If your dog strains and nothing comes out, then it may simply be stress, which gives him the urge to go despite having an empty colon. This is not to be confused with constipation. Most likely, the straining happens after your dog has already defecated several times. Diarrhea due to stress should resolve itself within 24 to 48 hours, so call a vet if it does not. You can prevent bloody diarrhea due to stress by first resolving the source of stress.

Many factors can influence your dog's well-being.

Many factors can influence your dog's well-being.

2. Dietary Indiscretion

If your dog is a dumpster diver or a counter surfer, then she probably ate something bad that gave her an upset stomach. This can be easily remedied with a bland diet or slippery elm bark.

3. Food Intolerances

Allergies or intolerances to food will cause an upset stomach that may result in vomiting, flatulence or diarrhea. Common food culprits include dairy, undercooked eggs, raw meat or bones, or fried or greasy foods. Chronic diarrhea may also be a result of eating foods that are toxic to dogs.

4. Intoxication

If you suspect that your dog has ingested poison or toxic foods, such as chocolate, gum or grapes/raisins, then symptoms of vomiting and chronic diarrhea will occur along with more serious signs of poisoning, such as wobbly gait, fatigue, fainting and seizures.

5. Recent Diet Changes

Did you recently switch to another brand of dog food? Sometimes, mucus or liquid feces is simply a sign that your dog's digestive system is trying to adjust to a new diet. If this is the case, introduce the new food slowly by mixing in increasing amounts with some of his old food. If your dog is not experiencing severe diarrhea or constipation and there is no sign of blood, then you can continue feeding the new food.

Your dog should be able to adjust within a week's time, and his stool should return to normal. If not, speak with your veterinarian. You may have to switch to a hypoallergenic food brand.

New foods should be introduced gradually.

New foods should be introduced gradually.

6. Inflammatory Bowel Disease (IBD)

Inflammatory bowel disease is a condition in which the intestine is chronically attacked by inflammatory cells. The most common type of IBD is characterized by an infiltration of lymphocytes and plasmacytes cells. This is common in German Shepherd and Shar Pei dogs. The second most common form involves the eosinophils cell.

7. Crohn's Disease

Also known as granulomatous colitis or regional enteritis, Crohn's disease is a chronic form of IBD. The first symptoms of Crohn's disease will be loose stool and a frequent urge to defecate. The stool may also contain bloody mucus. If the disease progresses, you will notice your dog becoming a picky eater, losing his appetite and losing weight.

8. Colitis

Large bowel diarrhea is often associated with colitis. You may also see straining (not to be confused with constipation) and small amounts of blood and excessive amounts of mucus. Stress is usually the leading cause, but colitis could also be brought on by an infection or parasites.

Histiocytic ulcerative colitis is a rare disease in which ulcers line the colon and cause inflammation with periodic acid-Schiff (PAS) positive histiocytes. If your dog has ulcerative colitis, you will see a lot of blood in his stool.

9. Presence of Parasites/Protozoans

Whipworms or tapeworms are parasites that live in the intestine and colon and cause severe irritation. They are some of the most pathogenic worms found in dogs and can be ingested via food, soil or water. If this is the cause of your dog's diarrhea, you may be able to find whipworm eggs in the stool.

Giardiasis is an intestinal infection caused by the protozoan parasite, giardia. This parasite is usually ingested from another animal's feces, including human feces. Dogs with giardiasis will exhibit foul-smelling diarrhea that is watery, frothy and contains a lot of mucus.

Dogs can contract whipworm by ingesting feces, so make sure to keep your yard clean.

Dogs can contract whipworm by ingesting feces, so make sure to keep your yard clean.

10. Fungal Infection

Histoplasmosis is a fungal infection that is contracted by eating or inhaling contaminated soil or bird droppings. Symptoms include loss of appetite and diarrhea with straining.

11. Small Intestinal Bacterial Overgrowth (SIBO)

SIBO occurs when the dog's body, for whatever reason, is unable to absorb raw food, so the bacteria already present in the dog's intestine eats the undigested food and uses it as fuel to grow and overpopulate. This causes an imbalance of good colon bacteria. SIBO is commonly seen in dogs with exocrine pancreatic insufficiency (EPI). German Shepherds are overrepresented among those who suffer from this disease. Symptoms include yellow mucus, loose/soft stool, mucus coating on the stool, flatulence, chronic diarrhea, crankiness and lethargy.

If the mucus in your dog's stools is caused by an imbalance of bacteria, Fortiflora is a probiotic that can help restore that balance.

12. Clostridial Enterotoxicosis

This disease is also characterized by an overgrowth of bacteria. The bacteria is usually acquired through raw meats and vegetables or decaying foods. Dogs with clostridial enteroxtoxicosis may experience diarrhea with a shiny mucus coating, frequent and watery stools, stomach discomfort and straining.

13. Parvovirus

This is a highly contagious viral disease that attacks the intestinal tract. The symptoms of parvo are lethargy, severe vomiting, bloody diarrhea, loss of appetite and life-threatening dehydration. Puppies, adolescent dogs and unvaccinated dogs are the most susceptible. Breeds at risk include Rottweilers, Dobermans and German Shepherds. If your puppy is infected, learn what you can do to save your puppy from parvo.

14. Ingesting Foreign Objects

If your dog has an appetite for non-food items, it could explain why he has digestive problems. This medical condition is known as pica and could be a symptom of a greater problem, such as malnutrition. But, most of the time, it is just a bad habit that must be stopped through training. If you're not sure whether your dog has swallowed something he shouldn't have, check for these major signs of intestinal blockage.

Check whether your dog might've eaten something he shouldn't have.

Check whether your dog might've eaten something he shouldn't have.

15. Polyps and Tumors of the Intestinal Lining

If you see rectal bleeding, it may indicate that polyps or tumors have grown inside your dog's intestinal lining or digestive tract. Please see a veterinarian as soon as possible if there is blood in the stool.

Treatment for Mucus in Dog Stool

Because some causes of mucus in stool can be serious, it's best to see a vet, especially if the dog has other symptoms such as diarrhea, vomiting, bloody stools, abdominal pain, fever or lethargy.

Why You Should See a Vet

Seeing the vet is useful because, through diagnostic tests, he/she can most likely pinpoint the problem and provide you with a solution to prevent the problem from recurring. In the case of parasites, the appropriate dewormer should kill all parasites and take care of all the associated gastrointestinal problems. Surgery may be needed if there is intestinal blockage or a polyp. Dogs with food intolerance may benefit from a hypoallergenic diet.

When It's Okay to Wait

In some cases, the episode of mucus in the stool will be short-lived, and the dog's stool will return to normal after a few days. If it's caused by a dietary indiscretion or a recent diet change, fasting and feeding a bland diet for a few days may help. Probiotics or yogurts containing live culture are also helpful for replenishing helpful flora in the gut. In mild cases, Imodium can be used under the guidance of your vet.

However, if your dog has other accompanying symptoms, and you suspect he might have gotten into something toxic, you should play it safe and see your vet promptly.

Why You Should Regularly Examine Your Dog's Stool

Welcome to the poop inspection club! I learned just how important the appearance of dog stool is while working for a veterinarian's office and working alongside vets in shelters. Dog owners used to drop off many stool samples and specimens of parasites they found. I quickly learned what the signs of trouble looked like. Now that I board and train dogs, I always check to see what their stools look like so that I can report any unusual appearances to their owners and take the dog to the vet if needed.

I recommend dog owners do the same, but don't rely on visual inspections alone. Dog owners sometimes tell me, "Oh, I know my dog is free of parasites because I look at his stools every day." Healthy-looking stools may be misleading, as there are many things the eyes can't see. For good reason, vets use microscopes to thoroughly inspect what's really in there. Yearly fecal exams are always recommended to keep things in check.

Visible and Telling Signs

Blood, parasites (at certain stages of growth), odd-looking consistencies and mucus are things that are visible to the naked eye that can tell you a whole lot about your dog's health.


  1. Amy Aitman, "Mucus in Dog Stool: The Common Causes," Care. Accessed December 7, 2017.
  2. "Mucus in the Stool in Dogs," WagWalking. Accessed December 7, 2017.
  3. Jennifer Coates, DVM, "How to Treat Mucus Stool in Dogs," PetMD. Accessed December 7, 2017.
  4. Scott Morgan, "Foods That Cause Diarrhea in Dogs," Cuteness. Accessed December 7, 2017.
  5. Foster & Smith, "Inflammatory Bowel Disease (IBD) in Dogs," Pet Education. Accessed December 7, 2017.
  6. "Parasitic Diarrhea (Giardiasis) in Dogs," PetMD. Accessed December 7, 2017.
  7. "Small Intestinal Bacterial Overgrowth (SIBO) in Dogs," VetStreet. December 11, 2011. Accessed December 7, 2017.
  8. "Diarrhea Due to Clostridium Perfringens in Dogs," PetMD. Accessed December 7, 2017.

This article is accurate and true to the best of the author’s knowledge. It is not meant to substitute for diagnosis, prognosis, treatment, prescription, or formal and individualized advice from a veterinary medical professional. Animals exhibiting signs and symptoms of distress should be seen by a veterinarian immediately.

Questions & Answers

Question: Is yogurt a good remedy to balance a dog's intestinal tract?

Answer: It depends. Not all dogs do well with yogurt. Some dogs may have a sensitive tummy and a certain degree of lactose intolerance. Therefore certain amounts can cause flatulence or diarrhea. It may be worthy to try giving a little at a time to see whether the dog tolerates it well. Commercial probiotics for dogs and veterinary grade probiotics may be more effective considering that these products are purposely, engineered to survive the high pH levels of the gut. It may be a good idea to consult with a vet for recommendations based on your dog's specific gut issues. Probiotics are often given long-term to dogs suffering from chronic digestive disorders.

Question: Are my dogs gums supposed to be bright red?

Answer: It's important to be familiar with your dog's normal gum color so that it's easier to recognize abnormalities. Normally, dogs gums are a nice bubble-gum pink or sometimes black depending on your dog's breed. Bright red gums are abnormal and would require investigation. How is your dog acting? Any exposure to toxins? Are the affected gums swollen and is there tartar accumulation? Please report to your vet if your dog has bright red gums.

© 2013 Adrienne Farricelli


Terri Minnick on May 18, 2020:

My golden retriever has had periodic bouts of blood & mucous in stools. No vomiting. He is a known rabbit poop eater and is constantly surfing the grass in our yard for it. Upon fecal examination ( even sent out to the lab) often comes back negative. I am convinced it is the rabbit poop causes the problem. PS this cleared up last time after a treatment of panacur even though fecal was negative.

sussi rael on September 12, 2019:

very informative, Thank You !

Harley on December 14, 2018:

My dog get a lot of bile in his tummy makes him sick and loose poops.

Lizbet156 on January 25, 2018:

My 7 month old puppy just had over a gallon of fluids removen from his abdomen and vet said congenital. Looking for help, but won't keep him alive and miserable. Help my husband loves him very much!!!!!!!!!

Rhonda Hudson on October 01, 2017:

My dog loves pumpkin and it's a great probiotic for dogs. I give her some every day.

JoAnn on September 12, 2017:

My dog has had really bad diarrhea the past couple days and its really mucousy.... I dont know what to do. I can't afford a vet

ScienceIsARealThing on July 07, 2017:

homeopathic hocus-pocus :( Why not just make a standing prayer to the flying spaghetti monster for good health - it's cheaper and there is equal science to support its positive effects. Better science actually as disproven claims regarding FSM are discarded as required by actual scientific discipline.

Vital Force on March 11, 2017:

yes, give Phosphorus 30C in addition to Arsenicum 30C. Both can be purchased at health food store. They are homeopathic remedies. There are no chemicals only natural remedy. Alternate every hour. Or put in water bowl. As a homeopathic practitioner for animals and own a chihuahua myself with bloody stools, I may suggest this.

Charlotte on March 04, 2017:

My 8 week old Chihuahua have blood in his stool and I don't have money for the vet is there anything I can do at home to keep him safe he's dehydrated but I've been giving him water and milk

Claudia D. Jones on February 27, 2017:

The article was helpful. I'm going to make a appointment with the vet.

Lainejones on December 31, 2016:

I'm needing advise on the quantity and feeding schedule to add yogurt to my two pups diet. They are both adult 11 pound Shih-Poos. The vet recommended probiotics after antibiotics did not correct the mucus in their stools.

carole butler on August 16, 2016:

i have a puppy cross yorkshire terrier with Pomeranian, I got from a pet shop I found out that pet shop owner was closed down before but now this shop is in her brothers name ! my problem is the pup has blood in stools sometimes his poo is just a little puddle with blood spots in I wormed with a complete worm pill ,,, still same yes I will take to vets ,but what can I do about pet shop she picked pup up out of 6 and handed over I did not get to look at the others I think she knew and wanted rid asap .

louise, rockys mum on June 13, 2016:

Hi, thankyou for all this info, Il b ringing me vet first thing in the morning to get rocky checked out just to be on the safe side. He is my baby and I don't want him in discomfort

teddi on May 15, 2016:

very helpful will try yogurt had full check by vet 2 weeks ago thank you

Colleen on April 18, 2016:

Thank you for the information. It was very helpful.

Adrienne Farricelli (author) on March 24, 2016:

Happy to hear this article on mucus in dog stool turned out helpful to you.

Parima on March 24, 2016:

Super thank you for the awesome info. I'm calling the vet tonight

Adrienne Farricelli (author) on September 01, 2015:

Thanks Dawn, what I read both forms are correct but mucus is used as a noun and mucous is used as an adjective. Will check and fix throughout where it was used incorrectly.

Dawn on September 01, 2015:

you have good information, but you spelled mucus wrong.