Dr. Tamara Godbey
There is nothing more frustrating than being woken all night listening to a pet scratch, chew and lick. And if you have experienced this, you know that it is probably equally as frustrating and sometimes painful for our beloved pets. Itch and subsequent scratching and chewing of the skin can be caused by many conditions and it may take several visits to the veterinarian to help determine the cause and prevent recurrence of itch.
First and foremost, our goal is to stop the itch to ensure your pet’s welfare. A pet that is scratching regularly, even when they don’t show evidence of itch during eating and play, is probably uncomfortable. Managing itch is often easier done today than it was 20 or even 10 years ago. There are many licensed and safe products to stop itch including Apoquel, an oral medication that “blocks” the itch pathway and Cytopoint, an injectable antibody that also stops the itch cycle. In addition the variety of therapeutic shampoos and other skin barrier treatments means we have many options to manage itch.
Often at the first visit, we want to rule out parasites as the cause of itch. The great thing about parasitic causes of itch is that we can often control or kill the parasites and prevent itch from ever returning. Some parasites can easily be seen on the skin, such as fleas. Other parasites live deeper in the skin and require further diagnostics to find them, such as a “skin scrape”.
The next goal is to identify skin infection. This may require several examinations of the skin and various tests from something as simple as an impression smear (a glass slide or clear tape are pressed to the skin) or something as advanced as a skin biopsy which would require sedation and pain control. Skin infections can be a primary cause of itch though often they are secondary to allergic skin disease or from trauma to the skin from scratching parasites. Once we can identify an infection, we need to treat. Treatment may be topical in the form of a shampoo, cream or ointment or may be an oral medication such as an antibiotic. Many times, skin infection requires long treatments of a few weeks to a few months to manage it.
What if the itch and or infection continues to return and no parasites have been identified? This is where we start to consider the possibility of skin allergy in your pet. Many pets can have flea allergy, where a few bites from a flea cause intense itching. It is highly recommended that any itchy pet be kept on a good quality flea preventative such as Credelio (dog) or Revolution (cat) regardless of whether fleas are found or if the pet has had fleas previously. Itchy pets often have heightened skin sensitivity and are more likely to over respond to even one flea bite.
Food allergy is another allergy affecting the skin of dogs and cats. We may recommend a food trial to help rule out food allergy. A common finding of food allergy is a pet that is itchy year-round and doesn’t not have seasonal itch. Our pet food industry has done a disservice to pets and their owners with the beginning of the “grain-free” fad. Many owners are led to believe that their dog or cat has a grain allergy and switch to a grain free diet, only to have their pet continue to itch. Many pets are actually allergic to the meat-based proteins in foods such as poultry, pork, beef or lamb. This is why many of the prescription diets for animals with food allergy have unique sources of meat protein such as alligator or venison or only fish. Some other prescription diets called “hydrolyzed diets” are made specifically for animals with food allergies and are “denatured” proteins that don’t stimulate the itch pathway.
Probably the most common cause of itch in an adult pet is atopic dermatitis, with 10% of dogs worldwide having this condition. This may be referred to as “seasonal allergy” and is diagnosed based on excluding any of the previously mentioned causes of itch. Basically, atopy is itch not due to parasites, bacteria, yeast or anything that is consumed including food and drugs. It is a chronic condition that cannot be cured but can be managed. Again, over the last 10 years the treatments available and our understanding of atopic dermatitis have allowed us to drastically improve the lives of itchy pets.
If you have an itchy pet, be prepared for multiple veterinary visits and trials to help work through the plan to identify the cause of itch. Then be prepared for a lifetime of managing your pet’s allergies which may improve and worsen at different times throughout life. We may even suggest a referral of your pet to a Dermatologist for further testing. We understand how frustrating chronic skin conditions can be and our goal, just like yours, is to get your pet comfortable.
For more information on specific treatments for itch, see: