Why does my pet itch?

Itchy pets can be a pain, not only for the animal with it’s incessant drive to scratch and lick, but also for it’s owner who’s been up all night from all the noise and commotion. The #1 cause of itchy skin is fleas, which is why a vet will use a flea comb to check for fleas and flea dirt. Common problem areas for fleas include: inner thighs, rump, base of the tail, and around the neck. It is essential to confirm proper monthly flea prevention with effective products.

Other creepy crawlies that can cause itchy cats and dogs include ear mites, demodectic mites, and sarcoptic mites. Testing for these includes checking swabs of ear debris and skin scrapings under the microscope. Fortunately, most prescription strength flea/tick preventatives protect against mites, including LAH recommended products of Revolution Plus, Bravecto, Simparica, and Simparica Trio.

Once fleas and mites have been firmly cleared as the culprit, the search becomes a little more frustrating. Roughly 70% of itchy dogs and cats have environmental allergies, which range from seasonal allergies such as grasses, weeds, and tree pollens that can peak in spring, summer, and/or fall, to nonseasonal environmental allergies such as molds, feathers, wool, as well as dust and storage mites. Pets with environmental allergies struggle with a vicious inflammation cycle. Allergic pets’ skin is hypersensitive to allergens absorbed through the skin and the normal function of the skin as a barrier against the outside world becomes damaged. Consequently, bacteria and yeast in the environment colonize the eroded and inflamed skin. These infections trigger further itch and inflammation, driving the pet to scratch, chew, bite, and lick even more.

Due to this vicious cycle, successful management of environmental allergies is multifaceted. One needs to repair the barrier mechanism of the skin, reduce the hypersensitivity to allergens, and treat the underlying infections. Allergic pets often require topical therapies such as bathing with shampoos, conditioning sprays and mousses as well as ingestion of essential fatty acids to repair the barrier function. Various medications can help reduce the hypersensitivity and itch, including Apoquel pills, Cytopoint injection, Cyclosporine, prescription skin support diets, as well as targeted Allergy Immunotherapy (desensitization). Lastly, skin infections are managed with topical and oral versions of antibiotics and antifungals to clear bacterial and fungal infections.

The remaining 30% of itchy dogs and cats are allergic to ingredients in their food. Contrary to popular media reports, grains are not a common source of itchy skin. Rather, it is the proteins in the pet’s food, with beef, chicken, dairy, fish, and lamb as the most common allergens. To diagnose a food allergy, a strict elimination diet trial is necessary. Everyone in the pet’s environment must be on board with the plan- no sneaking table scraps (intentionally from one’s spouse or accidentally from the toddler in a highchair), no dental chews, no treats from the mail carrier, and no flavored medications. After a successful trial, the pet is challenged with proteins and closely monitored to see if this induces an itch flare up.

Because pets’ itchiness can range from mild to severe and vary from seasonal to nonseasonal, discovering the underlying cause of itch can be frustrating and time consuming. If you are struggling with an itchy pet, please be prepared for a multimodal approach to diagnosing and managing your pet’s skin condition. Lastly, on a personal note, as the owner of two food and environmentally allergic dogs, I feel your pain. I will do my best to help your pet get the relief it needs.

Best, Meghan Ryan, VMD