Itchy skin, recurring ear infections, and upset stomachs are common complaints in dogs and cats. Sometimes the culprit is food, but it is easy to misdiagnose, so a careful approach is important.
Allergy vs. Intolerance
A food allergy involves the immune system reacting to a protein in the diet. A food intolerance does not involve the immune system but can still cause digestive upset. The symptoms can overlap.
Common Signs
- Chronic itching, especially around the paws, face, and ears
- Recurrent ear infections
- Vomiting or loose stools
- Excessive licking or hair loss
- Poor coat quality
Common Triggers
In dogs, beef, dairy, chicken, and wheat are frequently reported triggers. In cats, beef, fish, and chicken are common. Remember that environmental allergies and parasites can cause similar symptoms.
The Elimination Diet
The gold standard for diagnosis is a strict elimination diet trial lasting about 8 to 12 weeks, using a novel protein or a hydrolyzed protein diet prescribed by your veterinarian. During the trial, no treats, flavored medications, or table scraps should be given unless approved.
Do Not Self-Diagnose
Blood and saliva tests marketed for food allergies are not considered reliable by most veterinary dermatologists. Work with your veterinarian to rule out other causes and design a proper trial.