The Effects of Food Allergies on Dogs

Food allergies affect dogs in much the same way they affect humans. According to the Doctors Foster and Smith website, common allergens include beef, corn, chicken eggs, lamb, wheat, and soy. Food trials are typically used to diagnose food allergies: the suspected allergen is removed from your dog's diet; you note how this affects your dog; and then you reintroduce it to your dog. If he experiences problems as a result, your vet may conclude that your dog is allergic to that particular food.

  1. Skin Problems

    • Food allergies often affect dogs in the same ways that other allergies do. The Doctors Foster and Smith website states that food allergies can cause itchy skin and excessive scratching primarily on your dog's face, forelegs, armpits, feet, and anal area. He may also experience hair loss, skin infections, and hot spots, which are large sores on the skin that are often infected. Smelly and scaly skin is also a sign of food allergies, along with red pustules on the skin. If these symptoms are year-round or begin in the winter, then a food allergy, rather than a seasonal allergy, is probably the cause. In addition, if itchy skin isn't resolved after your dog is given steroids, a food allergy is probably to blame.

    Recurring Ear Infections

    • Dogs that experience recurring ear infections are typically suspected of having food allergies, states Dr. Rosanna Marsalla of the Pet Place website. Signs of ear infections include red, swollen ears; excessive scratching at the ears; and large amounts of discharge and debris coming from the ears. Even if ear infections are treated with cleanings and medication, they will continue to recur if food allergies are the cause. Food allergies are especially suspected when ear infections are caused by yeast.

    Gastrointestinal Upset

    • Diarrhea that is often accompanied by gas is another symptom of food allergies in dogs. When your dog can't properly digest or absorb a component in his food, such as milk or gluten, diarrhea will often result. According to Dr. Holly Nash of the website Doctors Foster and Smith, Irish setters and soft-coated wheaten terriers are often prone to experiencing this symptom as a result of gluten allergies. Food allergies can also cause a dog to vomit. While gastrointestinal upset is possible in a dog with food allergies, skin and ear problems are more common.