What Causes Diarrhea in Dogs and How to Treat It?

What causes diarrhea in dogs?

There are many potential causes of diarrhea in dogs. Diarrhea in is often caused by problems within the gastrointestinal tract (GI tract), which runs from the mouth to the anus and includes the esophagus, stomach, small intestine, and large intestine. However, diarrhea in dogs can also occur due to other illnesses outside the GI tract such as pancreatitis.

Some possible causes of diarrhea in dogs is originating within the upper GI tract include gastroenteritis (inflammation of the stomach and intestines), intestinal parasites, bacterial infections, viral infections (such as parvovirus or coronavirus), food allergies, inflammatory bowel disease, foreign body or toxin ingestion, or cancer, among others. 

Potential causes of diarrhea in dogs might originate outside the GI tract include pancreatitis (inflammation of the pancreas), distemper virus, liver disease, kidney disease, and stress, to name a few. Some medications, such as antibiotics, can also cause diarrhea in dogs. External causes like a stressful event or swallowing a foreign object, can cause your dog’s digestive tract and gut to produce diarrhea. Additionally, eating garbage can result in a pup’s diarrhea.

With so many potential causes of diarrhea, knowing about your dog’s history can help to narrow down the list for what’s causing dog’s diarrhea. For example, intestinal parasites are a very common cause of chronic diarrhea in puppies, especially those that were recently adopted or have not been fully dewormed. Dogs that eat human foods, especially fatty meals, are prone to developing gastroenteritis and/or pancreatitis. In unvaccinated dogs or young dogs that have not yet finished their puppy vaccines, viruses such as parvovirus, coronavirus, or distemper may be of concern. Noting the type of diarrhea may also help elucidate the reason for diarrhea in dogs.

Types of dog diarrhea?

Loose stool in dogs is often classified into 2 categories: small bowel diarrhea or large bowel diarrhea. Small bowel diarrhea is due to illnesses affecting the small intestine, such as parasites or viral or bacterial infections. It is characterized by normal to slightly increased frequency of large volumes of soft stool. Bleeding in the small intestine appears as dark black, tarry stool. Dogs with chronic small bowel diarrhea may lose weight over time due to decreased nutrient absorption. 

Large bowel diarrhea occurs due to disorders affecting the large intestine, like stress or parasites. It presents as increased frequency of small amounts of soft to watery stool. Affected dogs usually need to defecate urgently, strain during and/or after bowel movements, and may have mucus in the stool. Bleeding in the large intestine appears as bright red blood in the stool. Dogs can also have both small bowel and large bowel diarrhea when the small and large intestines are affected.

How serious is diarrhea in dogs?

Some causes of dog diarrhea are mild and may resolve without treatment or a bland diet, but others can be serious or even life-threatening and require veterinary attention. For example, dogs experiencing diarrhea due to stress may return to normal once they are no longer in a stressful situation. 

Oppositely, puppies that contract parvovirus can die from this disease, and veterinary treatment is required for the best chance of survival. Additionally, dogs with intestinal obstructions due to ingestion of foreign objects often require emergency surgery to remove the obstruction. As pet owners if you recognise this, you should visit the nearest emergency animal hospital. 

The duration and severity of diarrhea also determine the associated risk. Prolonged or explosive diarrhea may cause significant dehydration and loss of electrolytes which, if unresolved, can quickly become life-threatening. Bloody diarrhea is also particularly concerning in that, in addition to dehydration, it can cause anemia— a low red blood cell count resulting in poor oxygen delivery to the body.

When should you see the vet about dog diarrhea?

Diarrhea should always warrant a visit to the veterinarian in certain circumstances. As pet owners, it’s important that you know about treating diarrhea in dogs as it can become a very serious health issue. 

Dogs having liquid or watery diarrhea involving many episodes in a short period of time, diarrhea that appears black in color or contains red blood, or diarrhea that is accompanied by other symptoms such as decreased appetite, vomiting, lethargy, or abdominal pain, should always see a veterinarian on an emergency basis. 

Dogs with soft stool that does not contain blood may be in mild intestinal distress. If soft stool without blood lasts more than 48 hours, or if a dog’s diarrhea contains worms, the dog should also see a veterinarian, though these cases are usually less urgent.

When you visit your nearest emergency animal hospital, a veterinarian can perform the necessary diagnostic tests to try to figure out the cause of the soft stool, and administer any appropriate medication for dog diarrhea. The goal of treatment is to address the underlying cause of the diarrhea, and to prevent dangerous dehydration and electrolyte imbalances that can result from severe or prolonged diarrhea.

What to do at home when dog has diarrhea?

Dogs that have mild to moderate diarrhea without blood, eat well with normal energy levels, and have no additional symptoms may improve with at-home dog diarrhea treatment. 

Unless they require a specific prescription diet, dogs having diarrhea should be fed bland, low-fat, easily digestible foods for 3-5 days until the diarrhea resolves. It is not usually recommended to feed your dog’s regular food until the diarrhea is improved. Do not give your dog human medications unless directed to do so by a veterinarian, as some human medications are toxic to dogs.

Bland diets or specially formulated dog foods should be individually formulated to accommodate any dietary restrictions, but usually include a source of carbohydrates and protein. Example carbohydrates include white rice, baked sweet potato, unsweetened plain oatmeal, or canned pumpkin puree (NOT pie filling). 

Potential proteins include boiled skinless chicken breast (with no seasoning), boiled ground turkey or very lean ground beef (well drained), plain cooked white rice, or hard-boiled egg whites. Combine the ingredients in a 2:1 ratio of carbs:protein. Canned or dry GI-friendly prescription dog foods are also an option, and may be available through your veterinarian. Before feeding, talk to your vet about what bland diet, if any, would be most appropriate for your dog.

Other at-home options to treat dog diarrhea include probiotics. These are capsules, chewable tablets, or powder packets containing live beneficial bacteria that are given by mouth, often with a dog’s food, for a few days until diarrhea resolves. Yogurt contains probiotics, but as the sugar, fat, or lactose in yogurt may further upset a dog’s GI tract, this is not an ideal source of probiotics for dogs. Probiotics replenish the gut with “good” bacteria that protect against any “bad” bacteria causing disease in the GI tract. 

Products such as Proviable® and Fortiflora® are of good quality and available over-the-counter at the pet store or via online pet pharmacies. Probiotics are generally safe, but should not be given to dogs with compromised immune systems. Talk to your veterinarian before administering probiotics to ensure this is an appropriate treatment for your dog.

As dog owners, it’s important to ensure that dogs with diarrhea drink lots of water to make up for the fluids lost in the stool. To increase your dog’s water intake, you may try adding water to the food, feeding canned food instead of dry food, or offering running water (such as from a faucet or dog water fountain) rather than still water, as dogs may be more inclined to drink this way.