Stomach and Intestinal (Peptic) Ulcers in Dogs

Digestive fluids are acidic, which helps break down food in the stomach and intestines. If the stomach or intestinal lining becomes damaged, or if acid production becomes excessive, digestive juices can ‘eat away’ at the interior skin of the stomach, resulting in open, painful sores (ulcers).

Ulcers may bleed into the digestive tract leading to blood in stool. Left untreated, unresolved ulcers are not only painful but may lead to weight loss and nutritional deficiencies.

In severe cases, ulcers can perforate the stomach which can lead to life threatening sepsis or peritonitis.

Dogs that engage in extreme exercise or take high doses of certain medications are at an increased risk of developing GI ulcers.

The risk presented by GI ulcers varies. Minor ulcers may resolve on their own without ever causing symptoms. Severe ulcers can penetrate the stomach lining completely, allowing stomach contents, acids, and bacteria to enter the body cavity around the stomach. Subsequent infections are often fatal. If the ulcer exposes a large blood vessel to stomach acid, the vessel may burst and cause immediate, life-threatening blood loss.

There are also some conditions which result in GI ulcers that are more threatening than others, such as liver disease or cancer.

Chronic, slow bleeding from GI ulcers may lead to secondary anemia. Symptoms of anemia include weakness, pale gums, and rapid breathing.

Perforated ulcers usually lead to life-threatening sepsis and peritonitis with similar severe symptoms.

Digestive juices break down food, and the digestive tract’s interior lining protects the tissues from acidity. If the lining becomes damaged, or acid production increases beyond the lining’s ability to compensate, the lining erodes and sores develop in the stomach wall.

Conditions that decrease the ability of the lining to protect the stomach and intestine are more varied.

Gastrointestinal ulcers are sometimes asymptomatic, especially if the ulcer is small and shallow.

Blood may appear in the stool or vomit. Blood in vomit appears dark and grainy (like coffee grounds) as opposed to the usual red. This is because the blood has mixed with stomach acids. Digested blood that passes in the stool appears dark black and tarry.

Diagnostics include

• A physical examination
• Bloodwork
• Fecal analysis
• Urinalysis
• Parasite screening
• Diagnostic imaging
• Endoscopy

Treatment specifically targets the underlying cause of the ulcers when possible, such as medication which reduces gastric acid secretion or increases mucosal protection of the tract. In some cases, surgery may be necessary, as in cases of perforating ulcers.

Successful management of any underlying cause contributing to ulcer formation may be sufficient to allow ulcers to heal.

If the cause cannot be specifically determined, supportive therapy is indicated. This includes

• Fluids
• Blood transfusions for anemic patients
• Antiemetics
• Antibiotics for potential complications of septicemia or peritonitis

Follow-up appointments to monitor recovery may be required, especially if secondary anemia is occuring. The prognosis for GI ulcers is varied, depending on the underlying cause and severity. Mild ulcers and treatable underlying conditions have a positive prognosis. Conditions such as liver failure or GI cancers have a more guarded prognosis, and severe ulcers, such as those that perforate the stomach lining, have a poor prognosis.

The wide variety of conditions that may result in GI ulcers can make actively preventing them difficult. Some relevant strategies include:

• Use NSAIDs only when necessary at the minimum effective dose as prescribed by a veterinarian
• Optimal management of illnesses that contribute to ulcers
• Avoiding extreme exertion
• Keeping up with regular checkups and vaccinations

Early detection and management of the condition may prevent minor ulcers from becoming severe.

Gastrointestinal ulcers are not contagious.

GI ulceration is more common in dogs than cats. It is also more common in sled dogs, or other dogs that exercise excessively.

• Antibiotics
• Acid reduction
• Mucosal protection
• Surgery
• Supportive care