Hemorrhagic gastroenteritis—more accurately known as Acute Hemorrhagic Diarrhea Syndrome (AHDS)—is one of the most common causes of sudden onset bloody diarrhea in dogs. 

Although it has similar symptoms to other causes of bloody diarrhea, such as parvovirus and pancreatitis, it is a unique condition that occurs primarily in small breed dogs. 

While it is undoubtedly scary to see your dog having bloody diarrhea and vomiting, quick veterinary intervention can be a lifesaver, and the prognosis is good for most dogs who receive timely and aggressive treatment. 

Read on to learn about hemorrhagic gastroenteritis in dogs and what to do if your dog develops this common condition.

What is Hemorrhagic Gastroenteritis in Dogs?

Hemorrhagic gastroenteritis is a sudden onset of profuse bloody diarrhea, often in an otherwise healthy dog. Due to profuse diarrhea and significant blood loss, the condition can lead to rapid dehydration and can be life-threatening. HGE is often accompanied by abdominal pain and vomiting. Luckily, with prompt veterinary intervention and aggressive treatment, the prognosis is good, and most dogs will recover within a few days. 

What Causes HGE in Dogs?

We don’t know exactly what causes dogs to develop HGE. One theory is that it may be a hypersensitivity reaction to bacteria or certain dietary components. Several studies have also shown a correlation between the bacteria Clostridium perfringens (a common cause of food poisoning in humans) and dogs who develop HGE. Further research is needed to identify what causes HGE in dogs. 

Although we don’t know what causes HGE, we know that it is not contagious between dogs. It most commonly affects small and toy breed dogs, primarily the Yorkshire Terrier, Miniature Pinscher, Miniature Schnauzer, Maltese, Dachshund, Toy Poodle, Bichon Frise, Shetland Sheepdog and Cavalier King Charles Spaniel. Young to middle-aged dogs are most commonly affected.

HGE Symptoms in Dogs

Hemorrhagic gastroenteritis is characterized by a sudden onset of profuse bloody diarrhea. Symptoms often come on quickly over the course of a few hours. Many dogs also experience vomiting, often before the diarrhea starts, and in some cases, there may be blood in the vomit. 

Other symptoms of hemorrhagic gastroenteritis can include:

• Loss of appetite
• Abdominal pain
• Fever
• Dehydration
• Depression
• Shock
• Collapse
• Hypothermia
• Cool extremities
• Pale gums

If your dog shows any of these symptoms, this is an emergency, and you should seek veterinary care immediately. If left untreated, this condition can lead to severe dehydration and hypovolemic shock, which can be fatal.

Diagnosing HGE in Dogs

To diagnose hemorrhagic gastroenteritis, your veterinarian will first perform a complete physical examination and will take note of your dog’s medical history and current symptoms. Your veterinarian may also recommend some diagnostic testing such as:

Blood tests. These will be used to evaluate your dog’s red blood cell count, which can help diagnose hemorrhagic gastroenteritis. Blood work may also show other changes, such as a low protein level, which can indicate proteins are being lost through the gastrointestinal tract.

Radiographs (X-rays). X-rays of your dog’s abdomen will rule out other possible causes of diarrhea and vomiting, such as a foreign body, intussusception or gastrointestinal obstruction.

Parvovirus testing. This is performed to rule out parvovirus as the cause for your dog’s symptoms (parvo can also cause vomiting and bloody diarrhea).

Fecal evaluation. A stool sample will be reviewed to look for parasites and bacteria to determine whether these might be contributing to your dog’s diarrhea.

HGE in Dogs Treatment

Hemorrhagic gastroenteritis is a severe condition and requires veterinary intervention immediately. Without veterinary treatment, your dog can rapidly develop life-threatening dehydration and may go into shock due to blood and fluid loss.

Once under veterinary care, your dog will need to be hospitalized for intensive care, monitoring, and treatment. The mainstay of HGE treatment in dogs is aggressive intravenous fluid therapy to help rehydrate your dog and replace the blood volume lost due to diarrhea. Intravenous antibiotics will likely be administered. Some dogs may also need plasma infusions to help replace the protein lost due to the large volumes of bloody diarrhea they have experienced.

Medication for HGE in Dogs

In addition to fluid therapy, your dog will be given supportive care, which includes medications to help your dog feel better and to alleviate the inflammation in the gastrointestinal tract. 

Antiemetic medications will be provided either by injection or by mouth to help curb any ongoing vomiting. Gastroprotectant medications, such as omeprazole or pantoprazole, are also often given to protect the stomach lining from ulceration. Pain medications, such as buprenorphine, are administered to help alleviate abdominal pain and make your dog more comfortable. 

Probiotics are often prescribed to help regulate the intestinal microbiome and block pathogenic bacteria. Your dog will likely continue to receive probiotics when discharged from the hospital. Probiotics typically come in the form of a powder or capsule that can easily be sprinkled onto your dog’s food.

Your dog may also go home on a special low-fat, easily digestible diet, which can help prevent further GI upset. Your veterinarian may recommend transitioning back to your regular dog food after a certain amount of time or they may recommend continuing this prescription diet for the rest of your dog’s life.

Hemorrhagic Gastroenteritis Treatment Cost

Because dogs with hemorrhagic gastroenteritis require hospitalization and several days of treatment, this condition can be quite costly to treat. Pet owners should expect to spend between $500 and $1,500 on hospitalization and treatment, depending on the severity of the condition and number of days spent in the hospital.

How to Prevent HGE in Dogs

We don’t know exactly what causes HGE in dogs, so we unfortunately don’t know how to prevent it. Further research is needed to determine what causes HGE and what can be done to avoid this condition.

Related Conditions

• Parvovirus
• Pancreatitis
• Histiocytic Ulcerative Colitis
• Salmonellosis
• Campylobacteriosis