What to Know About Hydrolyzed Protein Dog Food

Published Jan. 6, 2023
golden pup eating out of silver dog bowl

Veterinary prescription dog food is used to manage a variety of health conditions in dogs, but the concept behind it isn’t always clear. If your veterinarian recommends a hydrolyzed protein dog food, you’re probably wondering what, exactly, “hydrolyzed” means.

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What Is Hydrolyzed Protein Dog Food?

Hydrolyzed protein dog food is a food in which the proteins are chemically broken down into tiny pieces through a water-based process called hydrolysis. This essentially makes proteins “invisible” to a dog’s immune system. 

Protein is a vital component to any diet. Your dog’s muscles, hormones and disease-fighting antibodies are all proteins. To make what their bodies need, dogs take proteins from food, break them down into building blocks called amino acids, and combine those amino acids into new proteins. 

In some animals, dietary proteins can trigger an abnormal immune response. Hydrolysis uses water to chemically break proteins into pieces that are so small that the immune system no longer reacts to them. 

Why Your Pet Might Need Dog Food With Hydrolyzed Protein

Veterinarians typically prescribe hydrolyzed protein dog foods to treat two conditions: food allergies and inflammatory bowel disease

Dog Food Allergies 

A dog’s gastrointestinal tract serves as a gatekeeper: It allows nutrients in while fighting off disease-causing microorganisms and keeping out anything else that is potentially harmful. But sometimes the body gets confused. Dog food allergies develop when the gut incorrectly starts identifying benign dietary proteins as a potential health risk and mounts an immune response against them. 

Food-allergic dogs can develop a variety of symptoms, including: 

  • Itchiness, which may involve the whole body or be limited to the feet, ears, and/or face 

  • Hair loss 

  • Skin lesions 

  • Recurrent skin or ear infections 

Digestive problems like vomitingdiarrhea, and excessive gassiness may or may not be present as well. 

Food allergy symptoms often begin when dogs are young (less than 1 year old) but can become evident at any age. Dog food allergies may develop soon after starting a new dog food or after years of eating the same diet. Food allergies are diagnosed in all types of dogs, but some breeds appear to be genetically predisposed, including: 

To diagnose dog food allergies, veterinarians typically recommend a food trial (usually lasting at least two months) during which dogs must eat only a hydrolyzed protein dog food or a diet made from a single-protein source that they have never been exposed to before. If the dog’s symptoms improve over this time and then reappear when they are fed their old food, a dog food allergy diagnosis can be made. 

Inflammatory Bowel Disease 

The line between food allergies and inflammatory bowel disease (IBD) is sometimes blurry. It’s thought that, in some cases, food allergies can develop as a result of IBD or vice versa. 

In any case, dogs with IBD have abnormal inflammation of their gastrointestinal tract. The inflammation may be widespread or localized, severe or mild, and these characteristics can change over time. This explains why dogs with IBD can have different symptoms that vary in their intensities. Signs of IBD can include: 

  • Vomiting 

  • Diarrhea 

  • Weight loss 

  • Increased or decreased appetite 

  • Lethargy 

  • Noisy gut sounds 

  • Increased gas production 

Inflammatory bowel disease can develop at any age, but it’s usually diagnosed in middle-aged to older dogs. Some breeds, including Boxers and German Shepherds, appear to be at a higher genetic risk for IBD. Inflammatory bowel disease can only be definitively diagnosed with a biopsy of the affected tissues. 

Hydrolyzed Protein Dog Food Recommendations

Treatment for dog food allergies and inflammatory bowel disease centers on finding a diet that does not trigger symptoms. Immunosuppressive medications and other treatments may also be necessary in severe cases of IBD. Once a dog has been diagnosed, they will likely need to eat a special diet for the rest of their life. 

Veterinary prescription hydrolyzed protein dog foods are an excellent choice for both food allergies and IBD. These diets are manufactured under the strictest quality control measures, which ensures that they aren’t contaminated by ingredients that are not included in the label. Eating triggering foods is a major reason that diagnostic food trials and treatment for food allergies and IBD fail. 

Hill’s Hydrolyzed Protein Dog Food 

Both of the following hydrolyzed protein dog foods also contain high levels of essential fatty acids to promote skin health:

Royal Canin Hydrolyzed Protein Dog Food 

Royal Canin Veterinary Diets come in several hydrolyzed varieties, including:  

Purina Hydrolyzed Protein Dog Food 

Purina Pro Plan Veterinary Diets come in: 

Your veterinarian can help you find the best hydrolyzed protein dog food that will keep your dog’s symptoms under control while still providing the balanced nutrition that’s essential to good health. 

Featured Image: iStock/nensuria 


Jennifer Coates, DVM


Jennifer Coates, DVM


Dr. Jennifer Coates is an accomplished veterinarian, writer, editor, and consultant with years of experience in the fields of veterinary...

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