“My dog has watery stools” is a common complaint heard at veterinary offices. Watery stools, or diarrhea, can be a symptom of many different medical problems. The severity of diarrhea can range from a simple upset stomach to a major medical emergency. However, in most cases, if a dog has watery diarrhea (i.e., when the stool is mostly water with just a small amount of fecal matter), it should be considered a medical emergency.
My Dog Has Watery Stools – Why?
Diarrhea is a symptom of many different diseases and illnesses in dogs, but it is not a disease in itself. While diarrhea is a common issue in dogs, it can be difficult to determine the actual cause. Some of the most common causes of acute onset diarrhea (diarrhea that occurs suddenly and at least three times in a 24-hour period) include:
- Dietary indiscretion
- Parasite infection
- Viral infection
Dogs are well known for being opportunistic when food is around, often eating just about anything. However, what they eat can sometimes cause gastrointestinal upset, leading to vomiting and diarrhea.
Upsets in digestion can occur in many ways. Abrupt changes in diet, feeding unfamiliar treats or table scraps, getting into the trash, or eating something outside can all cause stomach upset and lead to diarrhea. Depending on the amount eaten and the cause, many dogs can be treated at home by withholding food for 24 hours and then gradually introducing a bland diet until their stool returns to normal. In other cases, medical intervention may be required to help the dog recover more quickly.
Unfortunately, when dogs sneak a meal from the garbage, they don’t always discriminate between actual food and wrappers, containers, or other items in the trash. If you suspect your dog has eaten a foreign object, call your veterinarian immediately. While some items may decompose in the stomach and pass through the dog’s body without issue, others will not. The digestive tract is a long series of ever-smaller intestines, and many things ingested may not make it all the way through to pass naturally. If they get stuck in the intestines, surgery may be needed to remove the object. However, if medical attention is sought promptly after suspected foreign body ingestion, your vet may be able to induce vomiting and retrieve the item before it passes through the stomach.
Parasites are a common cause of diarrhea in both puppies and adult dogs. Intestinal parasites, such as hookworms and roundworms, are most commonly found in puppies, though any dog can be at risk. Roundworms are especially widespread in puppies, and if left unchecked, they can cause severe respiratory and intestinal problems, or even death. Puppies just a few weeks old can have a life-threatening infection. In addition to finding these long, spaghetti-like worms in their stools, affected puppies may have a pot-bellied appearance and a rough hair coat.
Giardia is a single-celled protozoa that lives in the dog’s intestines and is easily transmitted through contaminated water, food sources, or soil. Giardia is particularly common in areas with a high concentration of dogs, such as boarding kennels and dog parks. Diarrhea is the most common sign of Giardia, although some dogs may carry the parasite without showing symptoms. Fecal screening can help diagnose Giardia, enabling appropriate treatment. This is especially important, as Giardia is a zoonotic parasite and can be transmitted to humans, including children, from affected dogs.
In dogs under two years old, especially puppies, diarrhea should raise suspicion of canine parvovirus as a possible cause. This viral disease is extremely serious and often fatal without intensive medical care. Parvo attacks the cells that line the intestines, which are responsible for absorbing nutrients and liquids. This damage leads to profuse, foul-smelling watery diarrhea, along with a high fever, lethargy, and vomiting. The volume of diarrhea quickly causes severe dehydration, and young puppies can die within hours due to dehydration. Parvo can be diagnosed through an antigen test at your vet’s office.
What Should I Do?
Given the many potential causes of watery stools and diarrhea in dogs, it is up to the owner to be vigilant in caring for the dog and deciding when veterinary care may be necessary.
In mild cases of diarrhea—where the stools are soft but do not contain blood or mucus, and the dog appears otherwise normal (energetic, eating and drinking normally, bright and responsive)—it may be possible to treat the episode at home with a bland diet.
However, if the diarrhea becomes more watery (more water than fecal matter), contains blood or mucus, or if the dog is showing other signs of illness, a veterinarian should examine your dog to help diagnose and treat the condition before it becomes more serious.
At the vet’s office, fecal screening may be recommended to determine if internal parasites are the cause of the diarrhea. If your dog has eaten, or is suspected to have eaten, a foreign object or a large amount of food, radiographs (X-rays) may be performed to check the contents of the stomach and ensure everything will pass through the intestines without issue.
Depending on the severity of your dog’s illness, a full blood panel may be recommended to assess the level of dehydration (by checking the packed cell volume, or PCV), to check for an elevated white blood cell count (which may indicate an infection), and to perform full chemistries to evaluate the function of major organs (liver, kidneys, etc.).
As dehydration is the most common side effect of diarrhea, your vet may administer IV or subcutaneous (under the skin) fluids to help correct the dehydration.
While some episodes of diarrhea can be treated uneventfully at home, it is never a bad idea to have your vet examine your dog if it has watery stools. Your veterinarian will be able to determine why your dog is experiencing diarrhea and, more importantly, how to treat it.