Dog Has Diarrhea? Causes, Home Remedies, and When to See the Vet

Diarrhea in dogs can be frustrating, especially when it’s frequent, persistent, or contains blood or mucus. This article covers common causes, symptoms to watch for, and dog diarrhea remedies to consider alongside your vet’s advice.

Dog Has Diarrhea? Fast Facts

• It’s common for dogs to get an upset stomach sometimes, causing diarrhea that lasts up to 24 hours.
• Mild diarrhea can be caused by stress, scavenging, a change in diet, or a food sensitivity.
• Keeping a stable, low-fat, bland diet, offering small meals, and giving probiotics can help mild diarrhea resolve quickly.
• If your dog’s diarrhea lasts more than 24 hours or contains blood, or if they seem unwell or have other symptoms, seek advice from your vet.

What Counts as “Diarrhea”?

Diarrhea is watery or more frequent stools, often with urgency and straining. This symptom is an indication that something has irritated the digestive tract, but there are lots of potential causes, varying from a food intolerance or change in diet to more serious causes, like a gut blockage, cancer, or liver disease. Thankfully, mild cases of diarrhea usually clear up quickly with a diet change to small, bland meals and maybe some probiotics. However, if the diarrhea persists, the underlying cause may require specific treatment, like dewormers or antibiotics, or further tests to determine the best treatment.

“As long as a dog is acting well, eating, and drinking, I don’t normally worry about a couple of loose motions. But if they have diarrhea for more than 24 hours, or if it contains blood or they’re acting poorly, I like to see them for an examination.”

Common Dog Diarrhea Causes

1. Dietary Indiscretion

Many cases of mild diarrhea in dogs can be traced back to dietary indiscretion, where a dog has been through the trash or picked up something unpleasant on a walk. If mild diarrhea is the only symptom, most cases resolve within 24 hours with a bland diet.

2. Sudden Diet Change

Changing your dog’s food suddenly can disrupt their microbiome and lead to gut upset and diarrhea. To avoid this, change your dog’s food gradually over 7 to 10 days, adding a little more of the new food to their old food every couple of days.

3. Food Allergies or Sensitivity

Sometimes, certain ingredients, like meat proteins, dairy products, grains, or fillers, can cause a reaction if your dog has an allergy or intolerance. Food allergies tend to cause skin rashes and itchiness as well as diarrhea, whereas intolerances usually cause gastrointestinal symptoms.

4. Parasites (Worms, Giardia, Coccidia)

If a dog has persistent diarrhea, it’s important to check for intestinal parasites like worms and protozoa, particularly in puppies or dogs who haven’t been dewormed regularly. Aside from those transmitted from their mother as pups, most intestinal parasites are picked up from the environment. If your dog has worms or other intestinal parasites, you might notice weight loss and mucus or blood in their stools.

5. Bacterial or Viral Infection

Most causes of diarrhea don’t require antibiotics, but some more serious bacterial infections, like Salmonella and E. Coli, require treatment. Even viral infections, like Parvovirus, require antibiotics to treat any secondary bacterial infection. Dogs with an infection causing diarrhea will usually have a fever, profuse diarrhea, dehydration, and sometimes blood in the stools.

6. Stress or Anxiety

Diarrhea can be triggered by various stressors, including separation anxiety, moving home, traveling in the car, and fireworks. The symptoms usually improve without treatment once the stress resolves, but calming products and strategies can be helpful to prevent future flare-ups.

7. Medication Side Effects

Diarrhea is a side effect of some medications, including non-steroidal anti-inflammatory medications. It’s always important to report any suspected medication side effects to your vet. They may recommend stopping the medication, and there may be an alternative.

8. Chronic or Serious Illnesses

Not all diarrhea responds to a bland diet and time. Causes of persistent diarrhea include inflammatory bowel disease, liver disease, pancreatic enzyme deficiency, and cancer. If your dog’s diarrhea doesn’t improve quickly, or if they have other symptoms or are unwell, see your vet as soon as possible.

When It’s Just a Mild Upset (and What You Can Do at Home)

If your dog is well but has mild diarrhea and no other symptoms, try the following steps:

Step 1: Fast for 12–24 hours (not if a puppy)

A break from food will allow the gut to reset, but remember to keep water available. Never fast puppies, toy breeds, or diabetic dogs.

Step 2: Offer bland food

Feed your dog small amounts of boiled chicken, white fish, or scrambled egg (no milk) with white rice. Continue small, frequent, bland meals for 2-3 days after the last soft motion, then gradually transition to their usual food.

Step 3: Encourage drinking

When ongoing diarrhea is causing fluid loss, dehydration is a concern. To try to maintain your dog’s hydration, offer small amounts of water regularly. You can check your dog’s hydration by lifting the loose skin on the scruff of their neck, then letting go – it should quickly fall back into place.

Step 4: Add Digestive Support

Diarrhea can cause an imbalance in the gut microbiome, so probiotics can be helpful to restore the gut flora.

Step 5: Monitor

Most mild diarrhea in dogs resolves within 24 hours, but if it persists, speak to your vet for advice.

When to See the Vet

• Diarrhea lasting more than 24 hours.
• Diarrhea in a puppy, an elderly dog, or a dog with other health problems.
• Bloody or black, tarry feces.
• Other symptoms like vomiting or lack of appetite.
• Lethargy, fever, or dehydration.
• Known ingestion of a toxin or foreign material, or visible debris in the stools.

If your dog is dehydrated or very lethargic, won’t drink or can’t keep fluids down, don’t try any dog diarrhea remedies - it’s essential to take them to an emergency vet.

Finding the Cause of Diarrhea in Dogs

To find the cause of your dog’s diarrhea, your vet may check the following:

1. History: To find out when the diarrhea started, any other symptoms, and any obvious cause.
2. Physical exam: To check hydration, temperature, and for any abdominal discomfort.
3. Fecal exam: To check for parasites and bacterial infections.
4. Blood tests: To check hydration and assess the health of the organs (liver, pancreas, etc.)
5. X-rays or ultrasound: To check for foreign bodies, inflammation, or cancer.

If the cause is still unclear, your vet may recommend a diet trial, biopsies, or a medication trial, depending on the findings.

Tips to Prevent Diarrhea

• Always transition gradually when changing your dog’s food.
• Keep your dog’s diet stable and avoid tidbits and fatty treats.
• Keep trash secure and out of reach.
• Use regular, vet-approved parasite prevention products.

FAQs

Summary

Most mild cases of diarrhea in dogs resolve on their own with a bland diet, but some causes of diarrhea need investigation and treatment from your vet. A brief stomach upset is common in dogs,but knowing whether to manage them at home or call your vet ensures your pup feels better fast.

Dr. Hannah Godfrey BVetMed MRCVS

Hannah graduated in 2011 and works as a small animal vet in Cardiff, UK. She loves meeting people and their special pets and has a particular interest in diagnostic imaging, soft tissue surgery, and dentistry.

Feature image: istockphoto