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  1. dogs digestive health

Dog Digestive Health Tips

Dog Digestive Health Tips

Dog digestive health guidance from Fuzzy vets to help pet parents treat the most common dog stomach issues.
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The Most Common Causes of Diarrhea in Dogs

Posted by Dr. Roth on July 26, 2022

Wellness Care
Dogs Digestive Health Blog Featured Image The Most Common Causes of Diarrhea in Dogs

Pet parents get to know their canines pretty well. Over time, they learn their dog's quirks, favorite toys, and even the things they don't like. After going on several walks and picking up after them, pet parents also get to know their dog's poop. So, when they notice that their dog has diarrhea, they might wonder what the causes of diarrhea in dogs are and if they need to be concerned. 

What Causes Diarrhea in Dogs?

Diarrhea isn't a specific disease but a sign of an underlying issue. The term refers to a loose, unformed stool. Dogs with diarrhea may go more often or excrete larger amounts than usual as fecal matter moves more quickly through their intestines. At the same time, less water and nutrients are absorbed.

Many dogs experience diarrhea at some point during their lives. It's a common symptom that occurs with many different potential health issues. While some are mild and easily treatable, others can point to something more severe. 

The following are four of the most common causes of chronic diarrhea in dogs: 

Inflammatory Bowel Disease

While called inflammatory bowel disease, IBD isn't actually a disease. It's a syndrome that occurs as a result of chronic intestinal inflammation. That inflammation interferes with the ability of the dog's intestines to absorb nutrients. What causes IBD is currently unknown. 

Diarrhea is one of the most common symptoms of IBD. Many dogs will experience a loss of appetite (and, subsequently, weight loss) if the condition goes untreated. Some dogs, however, will become hungrier. 

Diagnosing IBD usually involves a tissue biopsy of the suspected affected area, although a vet may also perform a fecal exam and blood test. Treatment may include dietary changes, B12 injections, or medications, depending on the results. 

Intestinal Parasites or Intestinal Infections

Several types of intestinal parasites can cause diarrhea in dogs, including:

  • Hookworms

  • Roundworms

  • Whipworms

  • Giardia

  • Tapeworm

Many of these parasites are more likely to affect (and have more severe consequences for) puppies and older dogs with weakened immune systems. For instance, roundworms can stunt growth, and hookworms can cause anemia. 

Along with diarrhea, other signs of intestinal parasites include vomiting, lethargy, weight loss, and a dull coat. A vet can diagnose parasites with a fecal exam, and treatment often involves an anti-parasitic medication or antibiotics. 

Intestinal infections can develop from a viral or bacterial infection, such as salmonella, parvovirus, or distemper. Symptoms depend on the specific bacteria or virus present, but diarrhea is one of the most common. Diagnosis may involve a biopsy and stool sample testing, and treatment depends on the results. While pet parents may think they need to look for a dry nose to indicate if something isn't quite right, that’s an old wives’ tale. They should look for other signs and symptoms.

Foreign Object Ingestion

Dogs chew for a variety of reasons. Puppies gnaw on almost everything they encounter as they explore the world around them. Chewing can also help alleviate pain caused by teething. For adult dogs, healthy chewing behavior keeps their jaws strong and their teeth healthy. It can also provide stimulation, alleviating stress or boredom. 

One issue with chewing is that dogs can accidentally ingest something they shouldn't. Even dogs with healthy chewing behaviors can break off pieces of their toys or bones and swallow them. While some foreign objects can pass through the digestive system with no problem, others can get lodged in the intestines and create an obstruction. 

Dogs with a partial intestinal obstruction often develop diarrhea. When they defecate, liquid squeezes around the object. Other common symptoms include vomiting, appetite loss, lethargy, and abdominal pain. In addition to causing discomfort, a foreign object lodged in a dog's intestines can lead to necrosis (tissue death) or rupture of part of the intestines. 

A vet can usually diagnose foreign body ingestion with X-rays. They may also recommend exploratory surgery to remove the object and assess the dog's overall condition. Blood and urine tests can help determine if the dog may have developed any other health issues due to an obstruction.

Note: Some foreign bodies can result in complete intestinal obstruction. In other words, the dog can't pass anything through their intestines. In more advanced cases they may strain to defecate, but earlier symptoms to notice are if they seem to be feeling poorly, are not eating, are vomiting. The situation requires immediate emergency care.

Food Intolerance

Like humans, animals can develop food intolerances and allergies to many different food ingredients. The top culprits include beef, chicken, eggs, and wheat gluten, and some canines also develop allergies to different food additives. 

Egg allergies impact about one in twenty dogs. Wheat allergies are about one in ten. So, while they are technically in the top five culprits of food intolerance for dogs, they are nowhere near as common as beef (one in three), chicken (one in seven), and dairy (one in seven) intolerances. 

Food intolerances typically develop over time, so pet parents might not know there's a problem right away. In addition to diarrhea, a dog may experience:

  • Skin itchiness (which can lead to increased scratching, hot spots, and fur loss)

  • Frequent paw licking

  • Recurrent ear infections

  • Vomiting

An elimination diet is one of the most effective tools for diagnosing food intolerance. The process involves feeding the dog a hypoallergenic diet for eight to twelve weeks (to eliminate all potential allergens from their system). The food must not have any potential allergens the dog has eaten in the past. Pet parents also won't be able to provide treats, supplements, or other edibles during this time. 

If the symptoms disappear, the pet parent will need to gradually reintroduce the dog's regular food and watch for a reaction. A return of the dog's symptoms typically indicates a food intolerance or allergy. Treatment usually involves changing the dog's food to a hydrolyzed protein diet or prescription diet that contains proteins not present in their previous food. 

What To Do When Your Dog Experiences Episodes of Diarrhea 

Usually, a single episode of diarrhea with no other symptoms (the dog is acting normally) isn't a cause for concern. Even so, the pet parent should monitor their dog for any unusual changes. In the case of chronic diarrhea, the canine may have developed a health issue.

Seek Out Veterinary Care

When a dog has experienced several bouts of diarrhea or ongoing diarrhea, seek veterinary attention as soon as possible, especially if the dog is very young or very old. A pet parent should also speak with a vet immediately if the dog exhibits additional symptoms such as vomiting, weakness, bloody stool, or signs of dehydration. If the dog appears to be in significant distress, consider going to the emergency vet immediately.

Adjust Your Dog's Diet

Not all food-related diarrhea indicates an allergy or intolerance. In some cases, a dog may not be getting the right balance of nutrients. A dog may be overeating or getting into the trash bin and ingesting spoiled food. 

In these cases, an adjustment to the dog's diet may be necessary. A pet parent might need to change to a different dog food brand, alter portions, or incorporate supplements. An experienced online vet can offer nutrition guidance that can help get a dog's digestive system back on track

Treat Your Pet's Upset Stomach

Diarrhea isn't uncommon in dogs. Mild bouts often result from stomach upset, and they often resolve on their own pretty quickly. However, if the dog experiences several issues and additional symptoms, it may be time to speak with a vet. 

Fuzzy is here to help. With a team of licensed vets available 24/7, you always have access to an experienced professional who can help you assess the situation and determine the next steps they need to take. To unlock Fuzzy's Live Vet Chat (and several other incredible benefits), sign up to become a Fuzzy member today.

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