EPI in Dogs: Symptoms, Causes, and Treatment Explained

Dog owners with pets who have experienced stomach upset or diarrhea may have heard of exocrine pancreatic insufficiency, or EPI, in dogs. While most cases of gastrointestinal upset are not caused by EPI, understanding what the condition is can help you recognize its signs and get your pup the care they need. 

Dogs with EPI can live full, active lives with the right veterinary care and a commitment to ongoing treatment. Here’s what dog owners should know about pancreatic insufficiency, including symptoms, causes, diagnosis, and EPI in dogs treatments.

What is EPI in dogs?

Exocrine pancreatic insufficiency (EPI) is a problem with digestion that affects how dogs break down and absorb nutrients from food. The pancreas is a small organ near the stomach and small intestine. It has two main jobs: the production of digestive enzymes (exocrine function) by pancreatic acinar cells and the production of hormones, such as insulin (endocrine function), by beta cells. 

Pancreatic enzymes include:

• Lipase: Breaks down fats
• Trypsin: Digests proteins
• Amylase: Breaks down carbohydrates

Without these digestive enzymes or an enzyme supplement, food passes quickly through the GI tract without breaking down, causing dogs to lose weight despite a ravenous appetite. 

Symptoms of EPI in dogs

EPI in dogs symptoms may come on slowly, but they can worsen quickly as dogs lose exocrine function and become malnourished. Symptoms to look for include:

• Ravenous appetite: Dogs with exocrine pancreatic insufficiency are extremely hungry because their bodies aren’t absorbing enough nutrients from the food they eat.
• Weight loss: Dogs with EPI lose weight despite an increased appetite.
• Soft, greasy, or foul-smelling stool: Stools become pale, soft, and oily from fat passing through the system—a condition called steatorrhea.
• Eating feces: Some dogs with EPI eat their own stool (coprophagia), as it contains mostly undigested food.
• Eating non-food items: Along with coprophagia, dogs with exocrine pancreatic insufficiency may chew on or swallow unusual things like dirt or rocks, a condition called pica, due to cravings from being malnourished.
• Excess gas and diarrhea: Intestinal problems, such as chronic diarrhea and gas, are common in dogs with EPI because altered digestion disrupts the balance between good and bad bacteria. EPI can also cause problems with water balance in stools.
• Poor coat quality or flaky skin: Nutrient deficiencies can affect your dog’s entire body, including their skin and coat quality. Dogs lacking digestive enzymes can’t absorb enough vitamins, fats, or omega fatty acids from their food, causing dull fur and flaky or greasy skin.

Some dogs develop exocrine pancreatic insufficiency secondary to another problem with pancreatic function, such as diabetes or pancreatitis. These dogs may show symptoms associated with those disorders, such as vomiting, increased thirst and urination, decreased appetite, or lethargy. 

Causes of exocrine pancreatic insufficiency in dogs

There are several possible causes of EPI in dogs. The most common include:

• Pancreatic acinar atrophy: This is the most common cause of EPI in dogs, typically affecting young adults. Pancreatic acinar atrophy is an autoimmune condition in which the dog’s immune system attacks and destroys the pancreatic cells that produce digestive enzymes, leading to diarrhea and other signs of EPI.
• Chronic pancreatitis: Long-term or recurrent bouts of pancreatic inflammation can gradually damage the pancreatic enzyme-producing (exocrine) tissues. Chronic pancreatitis is most common in older dogs and small breeds. In some cases, chronic pancreatitis also damages the beta cells that produce insulin, leading to diabetes.
• Genetic predisposition: Some breeds are at higher risk of developing EPI, suggesting that genes likely play a role in the gradual loss of pancreatic enzymes. While any breed can develop EPI, German shepherds are more frequently diagnosed than other breeds. Rough collies may also have an increased risk.
• Pancreatic tumors or congenital issues: Less common causes of EPI in dogs include tumors in or around the pancreas that can destroy acinar cells and cause loss of exocrine functions. Rarely, puppies may be born with congenital pancreatic insufficiency, causing intestinal problems and issues with digestion that start shortly after birth.

How is EPI in dogs diagnosed?

Veterinarians who suspect exocrine pancreatic insufficiency based on diarrhea, vomiting, or other symptoms and a history suggesting EPI may recommend a series of tests to rule the disease in or out.

There are many other possible causes of weight loss, increased appetite, and chronic diarrhea in dogs, so it’s important that a veterinarian determine the root cause before treatment is started.

Blood chemistry test and complete blood count

A blood chemistry panel and complete blood count (CBC) provide insights into your dog’s overall health. Dogs with EPI may have low protein or fat levels in their blood or signs of pancreatic inflammation. These general blood panels can also help to rule out infections or other causes of your pet’s symptoms, but they won’t confirm a diagnosis of exocrine pancreatic insufficiency.

Trypsin-like immunoreactivity test

The trypsin-like immunoreactivity (TLI) test is the gold standard for diagnosing EPI in dogs. This blood test measures the amount of trypsinogen, a precursor to the digestive enzyme trypsin, which is normally produced by the pancreas. Dogs with EPI have very low TLI levels because they are unable to produce the necessary pancreatic enzyme, and dogs with very high levels may have pancreatitis. To accurately measure exocrine function, dogs must be fasted for 12 hours before the test.

Vitamin deficiency and folate testing

It’s common for veterinarians to check vitamin B12 (cobalamin) and folate levels alongside trypsin-like immunoreactivity. Difficulty absorbing B12 from the small intestine is common in dogs with EPI, diarrhea, and several other disorders that affect digestion. In dogs with small intestinal bacterial overgrowth, folate levels may be high—another condition that can develop in dogs with exocrine pancreatic insufficiency or other digestive disorders. Seeing all of these values together can help your veterinarian narrow down your dog’s specific problem.

Ultrasound or endoscopy

Some dogs who are tested for exocrine pancreatic insufficiency actually have other diseases, such as inflammatory bowel disease, pancreatitis, or cancer, causing issues with digestion. Or they may have low pancreatic enzyme levels alongside another disease. If your veterinarian suspects any of these issues or isn’t sure about the diagnosis, they may recommend ultrasound imaging of the abdomen. Your vet may also suggest endoscopy, in which a dog is anesthetized and a camera is used to look at the inside of the gastrointestinal tract.

Treatment for exocrine pancreatic insufficiency in dogs

Once pancreatic acinar cells are destroyed, they can’t regenerate. This means EPI is not curable, but your veterinarian can help you control and manage the condition so your dog can resume normal digestion and maintain a healthy weight. 

EPI in dogs treatment centers on replacing missing digestive enzymes, correcting nutritional deficiencies, addressing microbiome imbalances, and helping restore the dog’s overall health. Only a veterinarian can determine the right treatments for dogs with EPI, which may include:

• Pancreatic enzyme supplementation: Dogs with EPI need a powdered pancreatic enzyme supplement mixed into their food for the rest of their lives. These supplements contain lipase, trypsin, and other enzymes your dog needs to restore exocrine function and digest food.
• Vitamin supplementation: Many dogs with exocrine pancreatic insufficiency need B12 shots or an oral supplement to restore normal levels and ensure continued absorption. Deficiencies may persist even after starting pancreatic enzyme replacement, so your vet may recommend checking blood levels to guide treatment.
• Antibiotics: Many dogs with EPI struggle with bacterial overgrowth in the small intestine, which may require short-term antibiotic treatment. Other options include intensive probiotic regimens or a fecal microbiome transplant, where gut microorganisms are transferred from a dog with healthy stools into your dog’s gastrointestinal tract.
• Dietary adjustments: Most dogs with EPI do best on a highly digestible diet with low or specific fiber, which may help reduce the amount of pancreatic enzyme supplementation needed to break down food. Your veterinarian can help you choose the right food and portion size for your pet. If your pet has other conditions, a custom or prescription diet might be needed.
  

Living with EPI: supporting your dog’s daily care

Managing exocrine pancreatic insufficiency is a lifelong commitment, but most dogs with the condition live long, healthy, normal lives with the right veterinary care. Consistent pancreatic enzyme supplementation, regular veterinary checkups, and ongoing monitoring of your dog’s weight and stool quality are important to helping a dog with EPI thrive.

Every dog’s health is unique, and their response to treatment for EPI can vary. It’s important to work closely with a veterinarian you trust and to find a diet and supplement regimen that works for your pet’s needs. Dogs with EPI need a highly digestible, nutrient-dense food to ensure they get maximum nutrition.