Colitis in Dogs

Colitis in dogs is a condition which occurs when the large intestine, or colon, becomes inflamed. Colitis interrupts the normal patterns of your dog's bowel movements and can lead to a variety of uncomfortable symptoms. There are two types of colitis: acute and chronic. While acute colitis is something that occurs rather suddenly and may not last long, chronic colitis continues over a period of time and can continue over the span of your dog's life. However, there are treatments available that most dogs respond very well to.

Causes of Colitis in Dogs

There are a variety of reasons and underlying causes that can contribute to the development of colitis. Some of the causes include:

  • Parasites
  • Bacteria
  • Trauma to the large intestinal area
  • Poor quality diet
  • Tumors or cancer
  • Inflammatory Bowel Disease (IBD)
  • Irritable Bowel Syndrome (IBS)
  • As a side effect of some antibiotics

Symptoms of Colitis

When colitis presents itself in dogs, it may not always be initially obvious. Some dogs will show very obvious clinical signs, while others will appear as though nothing is wrong. If your dog suffers from acute colitis, there may not be any visible signs of a problem. The symptoms listed below are most commonly associated with cases of chronic colitis.

  • Weight loss
  • Stools with mucous or blood streaked discharge
  • Straining during bowel movements
  • Pain during bowel movements
  • Continuous vomiting
  • Decreased appetite
  • Abdominal pain

Because colitis causes an inflammation of the colon, it's important to notice any abnormal changes in your dog's bowel movements.

How Does Colitis Affect Your Dog?

Because acute colitis occurs suddenly and chronic colitis develops over time, the effect on your dog can be quite different depending on which one he is experiencing. Acute colitis typically presents itself with very few symptoms. However, with chronic colitis, your dog may show more of the clinical signs. Unless your dog has a severe case, there is likely no true effect on your dog. In more severe cases, your dog may become lethargic due to pain, vomiting or loss of appetite. Because the colon is inflamed, there is likely a certain amount of pain or abdominal discomfort in both acute and chronic cases.


Initially, a fecal examination will be performed to check for a bacterial or parasitic infection. A biopsy, or scraping of the tissue inside the colon, will likely be performed. Once the intestinal tissue is tested, an accurate diagnosis of colitis can be made. Additional testing can include blood tests, x-rays and a urinalysis. Underlying conditions need to be known in order to effectively treat colitis.


Not all treatment methods can cure a dog entirely of colitis. However, most cases can be managed so that your dog will live a normal and healthy life. Depending on the severity of the situation and aside from any other issues, dietary changes might be all that are needed to treat your dog. You may need to switch to a food that your dog finds easier to digest. Keep trying until you find one that is both nutritional and easily digestible for your dog.

If your dog's condition has been caused by bacteria or a parasite, an antibiotic will be administered to treat it. Your dog will probably also be prescribed medicine to help reduce the inflammation and pain. There are also long-term medications available, in the event that your dog will need to remain on antibiotic treatment indefinitely.

The most important aspect of treatment is being proactive in recognizing any unusual signs in your dog. Because colitis will continue to recur if underlying conditions are not corrected, they need to be diagnosed, so the treatment for colitis will be effective.