Skin Disease (Canine Seborrhea) in Dogs

In canine seborrhea, the skin cells produce excessive keratinous material that causes dermatitis with flakes and scaling. Symptoms commonly develop on the back or feet, as well as inside pouches and skin folds. The sebaceous glands in the skin often overproduce a lubricating secretion called sebum as well, and many dogs with seborrhea have very oily skin. Others develop a dryer form of the disease with peeling areas of dry skin and lesions. Many dogs have a combination of both types of symptoms. Seborrhea can be inherited, especially in some breeds. Puppies may develop flaking skin as young as ten weeks old and show significant symptoms before they are eighteen months. More commonly, however, seborrhea is due to a secondary condition, such as an endocrine imbalance that upsets hormone levels in the body, or an allergic reaction that affects the skin. Bacterial and fungal infections are often found in combination with seborrhea; in some cases these may be the primary cause, in others they are opportunistic infections that develop secondary to seborrheic dermatitis. Scratching at itchy lesions can make the skin break and increase the chance of infection. Many dogs have a distinctive odor with seborrhea, especially if it is combined with a Malassezia fungal infection. In severe cases, dogs may lose patches of hair. Concurrent ear infection is also a common problem, especially with oily seborrhea.

Dermatitis with scales and flaking skin in dogs is caused by abnormal keratinization and hormone levels in the skin cells. Veterinarians call this canine seborrhea or seborrheic dermatitis. It can be an inherited problem in some breeds, but more commonly it occurs secondary to allergies or endocrine disease.

These are the symptoms you might notice in a dog with seborrhea.

• Large numbers of skin flakes in a dog’s bedding
• Patches of flaking skin, especially on the back
• Excessively oily skin
• Itching (pruritus)
• Thick crusted skin
• Odor
• Alopecia (hair loss)
• Ear infection

Types

The two different types of seborrhea can be found separately or together.

• Seborrhea oleosa (oily seborrhea) – dogs have excessively greasy skin and commonly develop concurrent ear infection
• Seborrhea sicca (dry seborrhea) – dogs have dry, flaky patches of skin

Primary dermatitis is more common in some breeds. It is still rare however; most seborrheic dermatitis is due to a secondary condition.

Primary or congenital seborrhea

• American Cocker Spaniels, English Springer Spaniels, Basset Hounds, West Highland White Terriers, Dachshunds, Labrador Retrievers, Golden Retrievers, German Shepherds, Shar Peis, Doberman Pinschers, Irish Setters

Secondary

• Allergies
• Many types of endocrine Imbalance (including Cushing’s disease and thyroid disease)
• Fungal infection (especially Malassezia yeast infection)
• Bacterial infection (pyoderma)
• Parasites (fleas or ticks)
• Poor diet
• Changes in temperature
• Obesity
• Poor grooming
• Cancer (especially cutaneous lymphoma)

The veterinarian will examine your dog’s symptoms and take skin scrapings and fluid cultures to analyze the cells at a microscopic level. Red pimples and pustules tend to suggest a concurrent bacterial infection, such as pyoderma. Hair loss, odor, and signs of itching are also relevant. Allergic reactions usually have a higher degree of pruritus than hormone imbalance from endocrine disease. Other symptoms, like excessive drinking and urination, can suggest an endocrine problem. The veterinarian will take bloodwork and complete urinalysis to check for systemic symptoms. Specific tests (such as an ACTH Stim test) may be necessary to definitively diagnose Cushing’s disease or thyroid imbalance.

Your dog’s age and breed can also be relevant. When seborrhea develops in young puppies, this is frequently a sign of inherited disease. Nevertheless, the veterinarian will still need to perform a number of other tests to eliminate treatable conditions that could be causing the problem. Older dogs will be more likely to develop secondary seborrheic dermatitis as the result of an endocrinopathy, or cancer, while younger dogs, under five years of age, are more likely to have an allergic source for the disease. Recent diet changes can be relevant, as well as any environmental changes like a recent move.

Treatment for canine seborrhea will focus on managing the symptoms and eliminating the cause if it is a secondary condition. Antibiotics and antifungal medication will be prescribed to treat concurrent bacterial and fungal infection, which is common. The veterinarian may choose an antibiotic based on a lab’s analyzation of your dog’s specific bacteria to avoid problems with antibiotic resistant staphylococcal bacteria. Ketoconazole or fluconazole are frequently given for malassezia infection. Medication may also be prescribed to kill fleas or roundworm.

Antiseborrheic shampoos are the most effective way of treating the flakes and scaling that are the defining symptoms of seborrhea. The veterinarian will prescribe or recommend a shampoo. In the first few weeks of treatment, you may need to bathe your dog two or three times per week. The shampoo will need to stay in contact with the skin for ten or fifteen minutes in order to have an effect. Moisturizers and sprays can be used after or between baths. The flaking may get worse to begin with, but will taper off as symptoms begin to be controlled. You will need to monitor your dog carefully as over-bathing can actually make seborrhea worse. If ear infection is present, the veterinarian will prescribe drops and you will need to clean the wax build-up out of your dog’s ears frequently.

Other treatments will focus on conditions that are causing secondary seborrhea. Medication may be prescribed to treat hormone imbalance. Diet change may be recommended to eliminate or find the root of an allergic reaction. You may need cut your dog back to a single protein and add in other foods slowly to see what substance is causing the reaction. If the condition cannot be pinpointed, it may be due to an autoimmune response rather than a direct allergen; the veterinarian may recommend an immune suppressant medication if the problem is very severe. If the root cause of your dog’s seborrhea turns out to be cancerous, surgery and/or chemotherapy may be necessary, but this is quite rare.

Recovery will depend on the cause of seborrhea. With primary inherited versions of the disease, medicated shampoos and sprays will be necessary throughout your dog’s life. Depending on the dog, symptoms can often be kept mostly under control, but you will need to monitor your dog’s skin and seek treatment as soon as you notice a problem developing.

Secondary conditions can often be eliminated by treating the cause. If Cushing’s disease or thyroid imbalance can be treated medically, this will usually eliminate or greatly reduce seborrhea, however, lifelong medication may be necessary to treat the hormone imbalance. Finding and eliminating the source of an allergic reaction can also effectively cure seborrhea; if the exact allergen is impossible to pinpoint you may need to continue to manage the problem symptomatically. If seborrhea is due to an infection or a flea infestation, treatment is often quite effective. Your dog’s exact prognosis will depend on the veterinarian’s diagnosis.