Enteritis and Gastroenteritis in Dogs

Key Takeaways

Enteritis refers to inflammation of the intestines, while gastroenteritis refers to inflammation of both the intestines and the stomach. These terms are very broad, and do not refer to any specific condition or cause. 

• The most common symptoms of these conditions are vomiting and diarrhea. 

• Uncomplicated cases resulting when a dog eats something unusual or poorly tolerated usually resolve on their own or with symptomatic treatment like GI rest and a bland diet

• When symptoms don’t resolve after a day or two, or if other symptoms such as lethargy, tacky gums, or abdominal pain develop, a more aggressive diagnostic and treatment plan is indicated

• The underlying conditions associated with gastroenteritis and enteritis vary widely, so specific treatment and prognosis varies similarly

• Some cases have the potential to be life threatening

A Closer Look: What are Enteritis and Gastroenteritis in Dogs?

Sudden diet changes or dietary indiscretion are the most common cause of inflammation of the stomach and intestines. These situations typically occur around the holidays or when guests are visiting, and especially when dogs receive table scraps or other treats outside of their normal diet. Dogs that break into trash cans or pick up food items on walks are also prone to these types of digestive upset. 

Enteritis and gastroenteritis are common in dogs, with most dogs having at least one episode during their lifetime. Dogs showing only vomiting or diarrhea who are still bright and energetic with a good appetite do not require emergency attention, although veterinary intervention may lead to more rapid recovery. Most cases resulting from eating something unusual or poorly tolerated resolve on their own within 2-5 days with appropriate supportive care and short-term dietary changes. These cases have an excellent prognosis. 

Dogs who don’t improve with symptomatic therapy within a day or two or who develop symptoms such as abdominal pain, appetite loss, lethargy, or tacky gums require prompt veterinary care. The prognosis for these cases depends on the underlying cause of illness.

Risk Factors

Dietary indiscretion and sudden diet changes are the most common causes of inflammation of the stomach and/or intestines. These cases typically resolve on their own, and have minimal or no other symptoms besides vomiting or diarrhea. These dogs are bright, alert, and are drinking and eating well. 

Dogs with more serious forms look and feel sick. Dogs whose vomiting and diarrhea does not resolve and also develop additional symptoms like:

• Appetite loss • Lethargy • Tacky gums (dehydration) • Abdominal pain • Blood in the feces • Frequent vomiting

require prompt veterinary care to investigate the root cause of illness.

Possible Causes

There are many potential causes of inflammation in the intestines and stomach. Further testing is required to determine the underlying cause and provide a more meaningful diagnosis. Causes include:

• Sudden diet change • Dietary indiscretion • Dietary intolerance • Food allergies • Bacterial infections

• Parasitic infections • Viral infections • Toxicities • Endocrine diseases such as hypoadrenocorticism

• Inflammation of the pancreas (pancreatitis) • Inflammatory bowel disease

Many causes of enteritis also affect the stomach, resulting in gastroenteritis. Some also affect the colon, resulting in enterocolitis. These medical distinctions help the veterinarian come to a diagnosis, but are generally indistinguishable based on symptoms alone.

Main Symptoms

The most common symptoms of enteritis and gastroenteritis are vomiting and diarrhea. In some cases, the diarrhea contains blood.

Testing and Diagnosis

Physical examination, medical history, and general assessment of overall health determine whether further diagnostics to investigate symptoms of enteritis are indicated. Dogs that are otherwise healthy are often managed through supportive care without further diagnosis. In these cases, dietary indiscretion or a sudden diet change are the presumed cause of enteritis. 

Dogs that show additional symptoms besides just vomiting or diarrhea, or have physical examination changes indicative of a more serious condition require further diagnostic work-up. Diagnostic tests include:

• Blood work • Diagnostic imaging • Fecal analysis • Specific microbial testing • Endoscopy • Biopsy

• Exploratory surgery

Steps to Recovery

Most treatments focus on supportive care, particularly in the case of dehydration. General approaches include: 

• IV or oral fluids • Antiemetics • Medications that increase intestinal movement • Prebiotics and probiotics

• Medications that prevent damage to the intestinal wall 

Short-term dietary changes are helpful in many cases. For the first 24-48 hours, withholding food allows the intestine time to rest and recover from inflammation. For the next 3-5 days, a bland diet consisting of low-fat foods such as boiled rice, boiled chicken, or low-fat cottage cheese helps return the intestine to normal function. Over time, the dog’s normal diet is reintroduced. 

Other treatments depend on the underlying cause. Examples include:

• Antibiotics • Anti-parasitic medications • Long-term diet changes • Vitamin supplementation

• Steroids or other anti-inflammatory medications

The vast majority of cases resolve on their own within 2-5 days. These dogs have an excellent prognosis with supportive care. More severe cases have a variable prognosis and expected outcome, depending on the underlying condition.

Prevention

Some causes of these conditions are contagious, such as canine parvovirus and some parasitic infections. Many of these conditions are preventable with routine vaccination and deworming. The most common cause of enteritis, dietary indiscretion, is often prevented by securing human food and food waste and preventing access to foods that are not part of a dog’s regular diet.

Are Enteritis and Gastroenteritis Common in Dogs?

Enteritis and gastroenteritis are common in dogs. Many dogs have at least one instance of self-resolving enteritis and/or gastroenteritis in their lifetime.

Typical Treatment

• Supportive care • Short-term dietary changes