If your dog has been suffering from vomiting, diarrhea or a combination of both, your poor pooch just might have a case of gastroenteritis. Gastroenteritis in dogs is a common condition that typically involves diarrhea and may be accompanied by vomiting. It can also have a bloody component referred to as hemorrhagic gastroenteritis (HGE) or Acute hemorrhagic diarrhea syndrome (AHDS). Though common, gastroenteritis can be frustrating, scary and — depending on its cause and its effects on the individual dog — challenging to manage.

Types of Gastroenteritis in Dogs

Gastroenteritis has many faces. It can present as diarrhea alone (anywhere from mildly soft stool to watery feces) or diarrhea with vomiting. Less often, it can manifest as vomiting alone, though if the condition is confined to the stomach itself, veterinarians may refer to it as gastritis.

Gastroenteritis is further separated into two types — acute and chronic. Acute gastroenteritis comes on suddenly. Chronic gastroenteritis occurs over the course of weeks, months or even years. Acute gastroenteritis usually goes away by itself; in other cases, it will progressively worsen until veterinary treatment is provided.

Causes of Gastroenteritis in Dogs

Gastroenteritis in dogs can have many potential causes. Anything that alters a dog's microbiome significantly can lead to the condition. Here's a list of possible causes:

  • Ingestion of spoiled or raw foods, or of non-food items
  • Viruses (parvovirus, distemper, etc.)
  • Intestinal parasites
  • Changes in intestinal flora
  • food allergy or sensitivity
  • Gastrointestinal (GI) ulcers
  • GI cancers
  • Foreign bodies
  • Intestinal obstruction
  • Genetic disease or predisposition

Unfortunately, it's usually difficult to pinpoint the exact cause of the condition. However, this doesn't mean that your dog can't be cured. In fact, most veterinary treatment is successful.

Signs of Gastroenteritis in Dogs

Gastroenteritis in dogs typically starts with soft stool that becomes progressively wetter. Later on, you may notice mucus in the stool, your dog straining to produce a bowel movement and/or defecation in the house. Here are other common signs:

  • Explosive and/or frequent bowel movements
  • Tarry feces
  • Large volumes of watery stool
  • Blood in feces
  • Lethargy
  • Restlessness
  • Abdominal pain
  • Nausea (drooling, swallowing frequently)
  • Vomiting

Dogs may display one or many of these signs, depending on the disease's severity and progression.

When to Take Your Dog to the Vet

Many dogs with gastroenteritis will appear surprisingly normal. They may show no signs other than a change in the quality, quantity, frequency or location of their stool. Dogs with HGE will have more obvious signs as mentioned above.

Since it's difficult to know whether a dog's condition will progress dangerously, veterinary care should be considered in all cases of diarrhea, especially for puppies, geriatric dogs or small breed dogs at higher risk of dehydration. Veterinary care is absolutely necessary if your dog shows signs of vomiting, nausea, blood, pain or lethargy.

How Gastroenteritis is Managed in Dogs

Calling your vet should always be your first consideration if you suspect an issue with your dog's digestive health. They can let you know the best recommendations for your dog and if your pet needs to be examined right away. In addition to medications or treatments for gastroenteritis, your vet may recommend supportive care measures such as:

  • Feeding therapeutic food that is highly digestible and easy on the GI tract
  • Add an electrolyte supplement to their drinking water, for enhanced hydration

Limiting strenuous activity such as exercise for a few days

The Role of Nutrition in Gastroenteritis

The role nutrition plays in gastroenteritis can't be overstated, especially given that inappropriate dietary choices are at the heart of many cases. You should feed your dog regular meals consisting of food known not to upset their stomach. Try not to change their food too quickly or add new ingredients suddenly or in large quantities.

Vets will typically recommend food low in fat and high in digestible fiber to treat (and prevent) most cases of gastroenteritis. If your dog has a food sensitivity or allergy, their vet may prescribe a hydrolyzed-protein or novel-protein diet.

Gastroenteritis is a pain for everyone — not least your pup. Thankfully, veterinary care can be successful in treating the condition.

Frequently Asked Questions

The duration of gastroenteritis in dogs depends on the cause and severity. Contact your  veterinarian, who can determine the severity and expected recovery time.

Seek immediate veterinary attention for:

  • Frequent diarrhea or vomiting

  • Decreased drinking or excessive panting (signs of dehydration)

  • Abdominal pain

  • Bloody or tarry stool

  • Lethargy (decreased energy)

Talk to your veterinarian if your dog has recurring GI episodes — they can investigate underlying causes and recommend long-term management. Most cases of dog gastroenteritis can resolve completely without long-term effects. However, complications can occur:

  • Severe dehydration may require hospitalization and IV fluids

  • Chronic gastroenteritis can develop if the underlying cause isn't addressed

  • Repeated episodes may indicate underlying conditions

Veterinary care and a veterinary therapeutic GI food can help limit recurring episodes.

If you are seeing these signs, contact your veterinarian — they can determine whether it's gastroenteritis and how to treat it. Signs of gastroenteritis in dogs may include:

  • Vomiting 

  • Diarrhea

  • Decreased appetite or disinterest in food

  • Abdominal discomfort (hunched posture, whining, restlessness)

  • Decreased drinking or excessive panting (signs of dehydration)

  • Lethargy (decreased energy)

Bloody stool or persistent vomiting can be a medical emergency — contact your veterinarian immediately.

Your veterinarian can assess the severity and help determine the expected recovery timeline for your dog. The duration of gastroenteritis in dogs depends on the cause and severity:

Seek veterinary attention immediately for:

  • Frequent diarrhea or vomiting

  • Decreased drinking or excessive panting (signs of dehydration)

  • Abdominal pain

  • Bloody or tarry stool

  • Lethargy (decreased energy)

There is no instant cure for gastroenteritis in dogs. Talk to your veterinarian for their recommended treatment plan — they may recommend management of multiple kinds:

Most mild cases can resolve within 2 to 5 days with proper care, but a veterinarian will need to determine severity.

Ask your veterinarian for a feeding plan — they can recommend the right food and transition schedule for your dog's recovery.

They may recommend:

  •  A veterinary therapeutic gastrointestinal food

  •  Watching for a return of clinical signs

Dr. Patty Khuly Dr. Patty Khuly

Dr. Patty Khuly is an award-winning veterinarian known for her independent thinking, her spirited pet advocacy, her passion for the veterinary profession, and her famously irreverent pet health writing.

Dr. K is an honors graduate of both Wellesley College and the University of Pennsylvania School of Veterinary Medicine. She received her MBA at The Wharton School of Business as part of the prestigious VMD/MBA dual-degree program. She now owns Sunset Animal Clinic, a veterinary practice in Miami, Florida.