A dog that scratches, licks, and digs at itself all day is one of the most common things owners bring to the vet, and allergies are usually behind it. The good news, says veterinarian Eileen Fatcheric, DVM, is that today’s treatments are safe and effective.
Whole Dog Journal executive editor Kate O’Connor sat down with Dr. Fatcheric to cover how to recognize dog allergies and what to do about them.
The two kinds of dog allergies
Dr. Fatcheric groups dog allergies into two broad buckets: food allergies and environmental (inhaled) allergies, known as atopy. Pinning down exactly what an environmental dog is allergic to is tough, so vets often treat the itch rather than chase every trigger. One clue that points toward food is timing: food-allergic dogs tend to itch year-round, while environmental allergies are often seasonal.
The sign to watch for
The hallmark of allergies, Dr. Fatcheric says, is normal, healthy-looking skin that itches. If your dog is thumping a hind leg, digging at its ears, or rubbing on the carpet, look at the skin first. If you don’t see lesions, pimples, scabs, or crusts when the itch starts, she treats that as allergies until proven otherwise.
Diagnosing a food allergy
You can’t diagnose a food allergy by grabbing a different bag off the shelf, because too many foods share ingredients. Instead, vets use a diet trial with one of two food types: a limited-ingredient diet (ideally a single novel protein the dog has never eaten, like fish, plus one carbohydrate) or a hydrolyzed-protein diet (a prescription food in which the protein is broken into pieces too small for the immune system to react to). The catch is that the trial has to run 8 to 12 weeks with nothing else passing the dog’s lips, which Dr. Fatcheric admits is hard in a house with toddlers.
Environmental allergies, testing, and shots
For environmental allergies, blood testing can identify common inhaled allergens, and some labs offer regional panels. But Dr. Fatcheric says the main reason to test is if you plan to pursue allergy shots (hyposensitization), which remain the gold standard in the literature but are slow and labor-intensive. Most owners, she notes, rely on medication instead, since today’s drugs calm the itch no matter what the dog is reacting to.
Medications that stop the itch
The two main players now are Apoquel, a daily oral medication, and Cytopoint, an injection given every four to eight weeks as needed. Dr. Fatcheric also mentions Atopica (cyclosporine) as an older option that still has a place. She explains, in plain terms, how these drugs interrupt the inflammatory cascade that ends in the itch.
Managing an itchy dog day to day
Beyond medication, Dr. Fatcheric points to medicated shampoos used at the right interval, spot treatment for localized irritation under a vet’s direction, and fish oil for its anti-inflammatory effect and skin support. One thing she tells every allergic-dog owner: do not skip flea and tick control, because an allergic dog can break out from a single flea bite.
The takeaway
Her long-term goal is simple: stop the itch, because a dog that keeps scratching ends up with secondary infections and a much bigger problem. Watch the full interview above, and work with your own veterinarian to find the approach that fits your dog.
