Diagnosing cutaneous food allergies in dogs and cats ‐ some practical considerations

PRURITUS is an extremely frequent presenting sign in dogs and cats and is most commonly caused by ectoparasites, infectious agents, such as bacteria and fungi, and allergies. The normal approach when investigating animals with pruritus is to rule out parasitic and infectious causes first. After this has been done, veterinary surgeons often make a tentative diagnosis of allergy. However, to establish a definitive diagnosis that allows successful long‐term management, it is often necessary to determine whether the animal is suffering from a food allergy, atopic dermatitis or a combination of the two. These conditions are clinically indistinguishable and atopic dermatitis can only be definitively diagnosed after food allergy has been ruled out. It is therefore important that a rigorous and logical diagnostic approach is applied when attempting to diagnose food allergy. This article discusses the many problems and pitfalls which need to be considered before a successful outcome can be expected.