Humans aren’t the only ones with allergies—our dogs can get them, too. Canine allergies can lead to numerous skin conditions that can be frustrating to manage. These allergies can be due to environmental causes or from the food our dogs eat.
Dog Food Allergy Symptoms
Generally, allergens are proteins that, once absorbed in the intestinal tract, can trigger an immune response that leads to problems in the skin. Occasionally, dogs can also develop inflammatory bowel disease-type symptoms, such as chronic diarrhea, chronic vomiting, and a prolonged decrease in appetite.
The most common symptoms of dog food allergies include:
Redness of the skin of the inner ears
Itchiness of the ears (or shaking of the head)
Chronic scratching of the ears
Chronic thickening of the ears
Redness and itchiness of the feet or in between toes (foot chewing)
Patchy hair loss along the neck and trunk
Chronic skin infections (with bacteria or yeast) that never seem to clear up
Skin issues are the most common dog food allergy symptoms. These are mostly seen as an allergic reaction to the proteins absorbed in food. That reaction leads to the release of immune cells, which can cause weakening of the bonds between the skin cells, resulting in a weakening of the skin “barrier.” This change in the skin barrier leads to redness and itchiness, and it makes the skin more susceptible to infection with normal bacteria and yeast. The most affected areas are the ears, paws, around the eyes, and sometimes the trunk and limbs.
What Are Common Dog Food Allergens?
The most common proteins dogs are allergic to are beef, chicken, lamb, and wheat. Other less common causes of dog food allergies include soy, eggs, corn, and nuts.
Dogs cannot be tested for food allergies like people can. The only proven way to tell what your dog is allergic to is to change their protein source or perform an elimination diet trial, where for 2-3 months you eliminate all proteins your dog has been exposed to from their diet. This gives the body enough time to completely eliminate the old protein sources and heal from the chronic allergy stimulation.
How to Help a Dog With Food Allergies
An elimination diet trial with hydrolyzed food is the best way to treat and diagnose a dog food allergy. It’s easiest to start with a prescription diet, such as Hill’s z/d or Royal Canin Hydrolyzed Protein. These veterinary diets have proteins that are too small to be recognized by the immune system.
An elimination diet trial takes approximately 2-3 months to complete. This time is necessary for the old proteins to leave the dog’s system. Additionally, the dog must be on the diet long enough to see a difference from the previous food. The most common mistake pet parents make is not waiting long enough before calling it quits on the diet trial. Changing what your dog is eating for just 1-2 weeks will not give you complete results, so taking the proper amount of time to test food and treats is crucial.
If the symptoms do not resolve after 2-3 months on the hydrolyzed elimination diet trial, your dog most likely has some type of environmental allergen. Or something else is causing the problem, such as an autoimmune condition or another undiagnosed condition, such as a skin infection.
If you get a good response from the trial, try to feed your dog a new protein source, such as venison, fish, or kangaroo. If they are going to react to these proteins, you should notice a mild reaction starting within 1-2 weeks. If their allergy symptoms return, stop the new protein source and go back to the hydrolyzed food.
Try adding one protein at a time every 2-4 weeks. If your dog reacts, stop and keep things steady for another two weeks before trying a different protein.
Contact your veterinarian before starting any diet trial to get a prescription for a hydrolyzed diet. It’s also important to see your veterinarian to make sure that your pet does not have any concurrent infections, which can be common because of the disturbed skin barrier caused by the allergic reaction. Infections can look the same as dog food allergy symptoms, so you must make sure to clear all infections during the food elimination trial.
During the trial, remember:
- Make sure the prescription treats and food are all that you are feeding your pet. You can’t feed human food or regular pet treats with a food trial, as it can introduce the allergens you’re trying to eliminate.
- Always introduce a dog to a new diet slowly to avoid stomach upset or diarrhea.
The Best Dog Food for Allergies
Hydrolyzed foods are the best dog food for allergies because the proteins are broken down into pieces that are so small the body can’t recognize them. Some of these foods include:
Novel protein diets include proteins that your dog has not been introduced to before, such as duck, fish, venison, and kangaroo. Some examples of novel protein diets are:
While it’s rare for puppies to have food allergies, there are some documented cases in pups as young as 6 months old. If you think your puppy may have a food allergy, lamb and rice formulas, such as Purina Puppy Lamb & Rice Formula, would be a good place to start for a novel protein.
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