Originally published 2019-07-19. Reviewed by Anything Pawsable on October 4, 2026.
Itching, ear problems and digestive upset have many possible causes. A food allergy is one possibility, but the symptoms alone do not identify an ingredient or distinguish allergy from other illness.
Start with your veterinarian
Bring a record of foods, treats, supplements, flavored medications and symptoms. The veterinarian can assess parasites, infections and other causes as well as diet.
Use a controlled diet trial
An elimination diet followed by a planned dietary challenge is the established way to investigate food allergy. Your veterinarian may choose a prescription hydrolyzed or appropriate novel-protein diet. Many trials need about eight weeks; the individual plan can differ.
During the trial, all food sources matter, including rewards, chews and flavored products. Do not stop a prescribed medicine on your own; ask how to fit it into the plan. Over-the-counter limited-ingredient diets may contain undeclared protein and are not equivalent to a controlled prescription trial.
Choose ongoing food carefully
Grain-free, starch-free, fresh or premium labels do not guarantee allergy control. No diet is universally nonallergenic. A home-prepared diet needs a properly qualified veterinary nutrition professional to make it nutritionally complete and suitable for the dog.
Once the cause and response are clearer, follow the individualized management plan and arrange rechecks if symptoms recur. Marketing claims and delivery subscriptions cannot replace diagnosis.