Flaky skin due to seborrhea is very common in pets. The term seborrhea refers to an increased production or a change in the quality of sebum, an oily lubricant and waterproofing substance secreted from the sebaceous glands in the skin. There are three main classifications of this skin condition with numerous causes. Seborrhea sicca, or dry seborrhea, is identified by dry flaky skin. Seborrhea oleosa is characterized by flaky skin with an oily, malodorous coat. Seborrheic dermatitis refers to either of the first two types along with inflammation of the skin and itchiness.
Seborrhea in general can be a primary or secondary skin disease. Primary causes would be genetic in nature. Some pets may inherit a hyperkeratinization problem of the skin, causing a rapid turnover of skin cells made apparent by profuse scaliness. In the vast majority of cases however, seborrhea is secondary to inhalant or contact allergies, infections of the skin, endocrine disorders, or ectoparasite infestation, i.e.: fleas, ticks, and mange mites. Bacteria and Malassezia yeast thrive in the presence of excess sebum and are very common contributors to seborrhea. In any case, seborrhea is the symptom, and the underlying cause must be diagnosed.
A small amount of skin flaking is normal in puppies and kittens, and young animals will do a bit of scratching as well. As long as the skin is not red and inflamed or the coat greasy and malodorous, there is generally no cause for concern. All pets should be routinely checked for fleas and ticks as a precaution.
In addition to a complete physical examination, the veterinarian may request blood work on a seborrheic animal to rule out metabolic or endocrine causes of the symptoms. Two very common causes of seborrhea in adult and geriatric dogs are hypothyroidism and hyperadrenocorticism. A reduction in the amount of circulating thyroid hormone, or an overproduction of cortisol, leaves the skin susceptible to numerous disorders including seborrhea. Allergy testing, desensitization therapy, and hypoallergenic feeding trials may help to identify a hypersensitivity to an inhalant, contact, or food allergen such as mold, pollen, or certain dietary ingredients.
Other diagnostic aids include skin scrapings, impression smears, and full-thickness skin biopsies in the worst cases of seborrhea. A skin scraping is used to identify mange mites, and an impression smear will reveal bacteria or yeast under the microscope. These types of infections will dictate the specific course of treatment necessary. Often, along with seborrhea, the pet may have concurrent ear infections or evidence of immune-mediated disease such as pemphigus foliaceus. Considering all of the patient’s presenting symptoms along with dietary history and environmental factors will help to narrow the diagnosis to one or more underlying causes.
If a disease mechanism can be identified, it will be addressed by a specific treatment protocol such as thyroid supplementation, antibiotic or antifungal drugs, treatment for mange mites, et cetera. Otherwise, the seborrhea will be treated symptomatically.
Medicated shampoos and topical agents are designed to remove excess sebum from the skin and kill bacteria and yeast. These can improve the itch and flakiness associated with seborrhea when used regularly. Grooming the coat to a shorter length may facilitate the removal of flakes and scales; this will also allow more oxygen to reach the skin, which will inhibit the overgrowth of microorganisms.
Omega 3 fatty acid supplementation can also help significantly in about 40 to 50% of cases. Fatty acids were once thought to add moisture to dry skin, but their benefit actually results from their potent antioxidant properties. They protect cells from damage and thus slow the rate of cellular sloughing from the skin.
Finally, hypoallergenic foods available only through veterinarians may be beneficial for those pets that have a dietary allergy leading to symptoms of seborrhea. It may take several weeks of restricting the pet’s intake to only one type of food in order to see results. Your veterinarian may prescribe a hypoallergenic diet for your pet as a diagnostic measure for food allergies.
It should be mentioned, that the number one cause of dermatitis in pets (skin disorders in general) is flea infestation. Regular use of a safe flea preventive product prescribed by your veterinarian may avoid a very common cause of seborrhea.