All dogs and cats will occasionally scratch and lick their fur coats. Often these behaviors are normal grooming activities. But if you have noticed your pet excessively scratching a certain area on her back, constantly licking aCat Scratching Selft his paws, or digging at her ears and shaking her head there may be an underlying health problem. Excessive itchiness, or pruritus, can lead to overaggressive grooming and scratching and will often coincide with changes observed on the skin and in the ears. Below is a review of some issues seen in dogs and cats that can cause or lead to itchiness and other dermatological problems.

Parasites
Ctenocephalides felis, the cat flea, is one of the most common ectoparasites seen in veterinary medicine. This blood sucking parasite not only feeds on cats but also dogs and other companion animals. Fleas alone do not typically cause excessive itchiness, but can sometimes cause over grooming in pets. Adult fleas will feed on the skin surface, but seeing them can be a challenge if your pet has a lush coat or long hair. While combing through a coat of a pet with fleas, you may discover black dirt-like specks peppered though the hair. This is the adult flea’s feces, also known as “flea dirt.” A simple at home test to determine whether this is “flea dirt” and not actual dirt requires only a damp paper towel. Placed on the damp paper, flea dirt should streak rust color after a few seconds. Integral to the prevention of fleas is the long acting flea product. Flea baths have their use, but results often only last for a few hours. If you are concerned about fleas with your pet, make sure to discuss all of your options with your local veterinarian. One thing to remember–never use dog-only labeled flea products on cats. The possible side effects could cause severe illness!

Another cause of itchiness or hair loss in cats and dogs are Sarcoptic and Demodectic mite infestations. Often referred to as mange, these species-specific mites can be seen in young, immunologically immature pets or elder pets that may have immunosuppressant diseases. Secondary skin infections (bacterial or yeast or both) can develop and significantly contribute to overall itchiness. Specific skin tests performed by your veterinarian can help with diagnosis. A combination of anti-parasitc medications and special shampoos are often used in the treatment of these mite infestations.

Allergies
Believe it or not, our pets can suffer from allergies too! One of the more common clinical manifestations of allergies is dermatologic. Flea allergy… this is where we can see some of the itchiest dogs and cats! Allergy to the flea saliva is the root of this disease. Presentation to the veterinarian of a dog or cat with severe flea allergy often involves severe barbering of the fur on the back half of the pet. Picture a pet without its pants. Severe redness and scabbing are also common symptoms. Flea preventative (year round for all pets in and out of the house) is crucial to the long term prevention of this disease. Treating of the house with area sprays is another way to keep flea infestations at bay.

Food allergies can also affect our pets and their skin. A food allergic dog or cat will often have itchiness of the face or neck. Dogs will also experience leg and foot itchiness. It can be challenging to determine what specific ingredient is causing the problem. Strict food trails (i.e. no other food, treats, or flavored medications) with veterinary prescription novel protein or hypoallergenic diets can help single out food allergy as a cause of dermatologic disease. It can take up to 2-3 months to determine a diet’s effect.

Environmental skin allergies (also known as atopy) are common in pets. Pollen, dust mites, storage mites, and molds are a few common antigens the immune system may create a hypersensitivity to. Allergy testing can be a useful tool in identifying these antigens. Individual immunotherapy (allergy injections) can be designed to cater to these environmental allergy sufferers.

Prescribed antihistamine use, omega 3 fatty acid supplements, topical products, antibiotics/antifungal, and corticosteroids are often involved in the treatment/prevention of allergies and secondary infections associated with allergic skin disease.

Diseases
Finally, there are a variety of endocrine diseases (hormonal diseases) that can contribute to skin disease. Hypothyroidism (low thyroid hormone levels) in dogs can affect the overall health of the skin, often affecting hair growth and leading to secondary infections.

Hyperadrenocorticism (Cushing’s disease–high steroid hormone levels) can lead to fragile skin and also lead to secondary infections. Lab testing is needed to diagnose these diseases and will lead to specific treatment options.

Hopefully this review of common skin maladies will help shed light on some primary causes of skin disease in our pets. It is important to contact your veterinarian if you observe any of the previous listed symptoms in your pet. With their help a diagnosis and treatment plan can be instituted. – Peter Olson, DVM

Peter Olson, DVM, is a 2007 graduate of The Ohio State University School of Veterinary Medicine. He and his wife Beth share their home with two dogs, two cats, four turtles and a Russian Tortoise.