Is seborrhea a bacterial infection

By Isabella Storyclaire

last updated September 16, 2024

Contributions sourced from

Seborrhea in Animals

For primary seborrhea, frequent bathing, along with vitamin A or a retinoid
For secondary seborrhea, treatment of the underlying cause
Antimicrobial treatment

Treatment for primary idiopathic seborrhea involves bathing the dog 23 times per week until the desired effect has been achieved. Bathing 12 times per week is generally sufficient for maintenance.

A shampoo regimen can resolve pyoderma, decrease the amount of scale and sebum present, decrease pruritus, and help normalize the epidermal turnover rate. Shampoos containing ceramides, ophytrium, or phytosphingosine are often effective; however, if greasiness persists, a benzoyl peroxide or selenium sulfide shampoo can be tried.

Systemic treatment with vitamin A (8,00010,000 units/dog, PO, every 12 hours, maximum 30,000 units/dog, PO, every 12 hours)or synthetic retinoids (eg, isotretinoin or acitretin [1 mg/kg, PO, every 1224 hours, decreasing to 0.5 mg/kg, PO, every 48 hours, for maintenance]) can be instituted if topical treatment is not sufficient. Synthetic retinoids are known teratogens and are classified as hazardous drugs in the US. In the US, isotretinoin and acitretin are subject to a risk evaluation and mitigation strategy (REMS) and may be difficult to obtain for nonhuman patients.

Treatment for secondary seborrhea is much more complex. For treatment of seborrhea with concurrent pyoderma, a shampoo with chlorhexidine, salicylic acid, or benzoyl peroxide should be instituted. An antiseptic mousse, spray, or wipe may be useful as well.

If topical treatment is not sufficient to resolve the pyoderma, then a systemic antimicrobial should be selected based on an aerobic skin culture and the most recent antimicrobial stewardship guidelines from the International Society for Companion Animal Infectious Diseases.

Because most staphylococcal infections in seborrhea cases are superficial pyodermas, they should be treated for 3 to 4 weeks.

Epidermal collarettes may be cultured using a dry sterile culturette rolled across the collarettes. Although methicillin-resistant S pseudintermedius infections are more difficult to treat, they are not more virulent or visually striking than those due to methicillin-susceptible S pseudintermedius. Hospitalization within the past year, surgery, and previous antibiotic treatment are all possible risk factors for development of methicillin-resistant S pseudintermedius infections.

Seborrhea with concurrent Malassezia dermatitis should be treated topically with an antifungal shampoo, mousse, wipe, or spray. A systemic antifungal such as fluconazole (5 mg/kg, PO, every 24 hours for 34 weeks) or itraconazole (510 mg/kg, PO, every 24 hours) may be used if topical treatment is not sufficient.

Most active ingredients in shampoos can be classified based on their effects as keratolytic, keratoplastic, emollient, antipruritic, or antimicrobial.

Topical keratolytic products include sulfur, salicylic acid, tar, selenium sulfide, propylene glycol, fatty acids, and benzoyl peroxide. They remove stratum corneum cells by causing cellular damage that results in ballooning and sloughing of the surface keratinocytes. This decreases the scale and makes the skin feel softer.

Shampoos containing keratolytic products frequently exacerbate scaling during the first 14 days of treatment because the sloughed scales get caught in the hair coat. The scales will be removed by continued bathing; however, owners should be warned that the scaling often worsens initially.

Topical keratoplastic products help normalize keratinization and decrease scale formation by slowing down epidermal basal cell mitosis. Tar, sulfur, salicylic acid, and selenium sulfide are examples of keratoplastic agents.

Topical emollients (eg, lactic acid, sodium lactate, lanolin, and numerous oils, such as corn, coconut, peanut, and cottonseed) are indicated for any scaling dermatosis, because they decrease transepidermal water loss. They are most effective after the skin has been rehydrated and are excellent adjunct products after shampooing.

Topical antibacterial agents include benzoyl peroxide, chlorhexidine, ethyl lactate, salicylic acid, and triclosan.

Topical antifungal agents include chlorhexidine, sulfur, ketoconazole, and miconazole. Boric and acetic acids are also used as topical antimicrobials.

Given that most shampoos are a combination of products, it is important to know how individual shampoo ingredients act, as well as any additive or synergistic effects they have. The selection of an appropriate antiseborrheic shampoo regimen is based on coat and skin scaling and oiliness:

mild scaling and no oiliness
moderate to marked scaling and mild oiliness (the most common)
moderate to marked scaling and moderate oiliness
mild scaling and marked oiliness

These categories are intended to guide the type of shampoo treatment necessary; however, all factors for each individual animal should be considered.

Patients with mild scaling and no oiliness need mild shampoos that are gentle, cleansing, hypoallergenic, or moisturizing. These shampoos are indicated for animals that have mild seborrheic changes, are irritated by medicated shampoos, or have been bathed too often. These products often contain emollient oils, lanolin, lactic acid, urea, glycerin, or fatty acids. Emollient sprays or rinses are often used in conjunction with these shampoos.

Patients with moderate to marked scaling and mild to marked oiliness should be bathed with shampoos that contain sulfur and salicylic acid. Both agents are keratolytic, keratoplastic, antibacterial, and antipruritic. In addition, sulfur is antiparasitic and antifungal. Some of these shampoos also contain ingredients that are antibacterial, antifungal, and moisturizing, which can help control secondary pyoderma, Malassezia spp, and excessive scaling. Shampoos that contain ethyl lactate lower the cutaneous pH (which has a bacteriostatic or bactericidal action by inhibiting bacterial lipases), normalize keratinization, solubilize fats, and decrease sebaceous secretions. These actions also result in potent antibacterial activity.

In the past, dogs with moderate to severe scaling and moderate oiliness were often treated with tar-containing shampoos. However, because tar shampoos usually have an unpleasant odor and can be irritating, along with poor owner compliance, they usually are no longer recommended.

In patients with severe oiliness and minimal scaling, profound odor, erythema, inflammation, and a secondary generalized pyoderma or Malassezia dermatitis are often present. Shampoos that contain benzoyl peroxide provide strong degreasing actions along with potent antibacterial and follicular flushing activities. Because benzoyl peroxide shampoos are such strong degreasing agents, they can be irritating and drying. Other antibacterial shampoos are better suited in animals that have superficial pyoderma without substantial oiliness. These shampoos usually contain 2%4% chlorhexidine (often in association with tris-EDTA) or ethyl lactate.

The follicular flushing action of benzoyl peroxide makes it helpful for patients with numerous comedones or with demodicosis. Benzoyl peroxide gels (5%) are good choices when antibacterial, degreasing, or follicular flushing actions are desired for focal areas, such as in localized demodicosis, canine acne, or Schnauzer comedone syndrome. However, these gels also may be irritating.

Seborrhea in Dogs

What Is Seborrhea in Dogs?

Seborrhea in dogs is a condition that affects keratin in the skin. Keratin is a protein that gives skin and hair its form.

In canine seborrhea, keratin is produced in the wrong amountseither too much or not enough. Seborrhea causes dogs to have a coat of hair thats dry and lackluster or greasy.

Seborrhea in dogs can be what veterinarians call primary or secondary.

Primary Seborrhea in Dogs

Primary seborrhea is a genetic disease that always causes the dog to produce abnormal keratin.

American Cocker Spaniels, West Highland White Terriers, English Springer Spaniels, and Basset Hounds are the most common breeds to have primary seborrhea, but any dog can have this condition.

Secondary Seborrhea in Dogs

With secondary seborrhea, an underlying issue is causing your dog to make abnormal keratin.

Health issues that can cause secondary seborrhea include:

Symptoms of Seborrhea in Dogs

Possible symptoms of seborrhea in dogs are:

Very dry, dull coat
Dandruff
Greasy, oily skin that smells bad
Crusted, plaque-like (rough and scaly) skin lesions
Itching that ranges from mild to severe
Large amount of earwax and ear debris

Generally, all the skin is affected by seborrhea, but the folds of skin between the toes, in the armpits, on the belly and perineum (the area under a dogs tail), and at the bottom of the neck are usually worse.

Dogs with lots of skin folds, like Basset Hounds, usually experience more affected skin in those folds.

Causes of Seborrhea in Dogs

The cause of a dogs seborrhea depends on whether its primary or secondary.

Causes of Primary Seborrhea in Dogs

Primary seborrhea is a congenital, genetic disease that typically starts at a young age and gets worse as your dog gets older. West Highland White Terriers, Basset Hounds, American Cocker Spaniels, and English Springer Spaniels are most commonly affected.

Causes of Secondary Seborrhea in Dogs

Diseases and other health issues that can cause secondary seborrhea in dogs include:

How Vets Diagnose Seborrhea in Dogs

Diagnosis of seborrhea starts with a physical examination by your veterinarian to check your dogs skin and look for other symptoms.

You will also be asked how long it has been happening, if your dog has been scratching, and if there are any changes in your dogs food and water intake.

Your veterinarian will perform testing to determine the cause of your dogs skin condition. The following tests could help:

A skin scraping to test for mites and lice
An impression cytology (collection) of skin and ear debris to test for a yeast or bacterial infection that looks like seborrhea, such as Malassezia yeast
A blood chemistry panel to screen for diabetes or Cushings disease (your vet will need further tests to confirm the diagnosis before starting treatment)
A blood test for thyroid hormone levels to determine whether your dog has hypothyroidism
A biopsy to look for autoimmune disease or cancer

Treatment for Seborrhea in Dogs

Based on the test results, your veterinarian will have a better understanding of what is causing your dogs seborrhea. The most important aspect of seborrhea treatment istreating any underlying conditions.

Treating the Underlying Cause

Hypothyroidism: If your dog has hypothyroidism, they are treated with hormone replacement, an oral medication called levothyroxine that your dog will take for the rest of their life.
Cushings disease: Treatment of Cushings disease involves lifelong medication called Vetoryl.
Diabetes: Treatment of diabetes requires daily insulin injections.
Cancer or autoimmune disease: If a biopsy shows that your dog has autoimmune disease or cancer, they will be started on medication to manage the disease, or your veterinarian may refer you to a specialist.
Lice or mites: If a skin scraping finds lice or mites, the veterinarian will put your dog on medication to kill the parasites.
Fleas: If your dog has fleas, a monthly flea preventative will curb flea allergies that can cause or worsen seborrhea.
Vitamin deficiency: If your veterinarian suspects vitamin A-responsive dermatitis or zinc-responsive dermatitis, they will recommend additional vitamins in your dogs diet.
Food allergy: If your veterinarian suspects a primary food allergy, they may recommend a hypoallergenic food trial.
Infection: If your dog has an infection that developed because of seborrhea, then the infection must be treated. Your dog will require a three- to four-week course of oral antibiotics and/or antifungals.

Treating the Seborrhea Itself

To treat the seborrhea itself, your dog needs frequent baths with anti-seborrheic shampoos, typically every 2 or 3 days to start with. These shampoos typically contain coal tar and salicylic acid.

Frequent bathing is continued for 2-3 weeks or longer, until the skin improves. The goal of bathing is to remove excess keratin. Depending on how your dog responds to treatment, bathing frequency may decrease to every 1 to 2 weeks, or it may stay at every 2 to 3 days.

Additionally, you will need to clean your dogs ears with a medicated ear cleaner every 2 to 3 days. If there is an infection in the ears, your veterinarian will prescribe an ear medication as well.

Your dog may also be started on prednisone to decrease inflammation and debris buildup. Regular rechecks with your veterinarian, typically every one to three weeks, are important to monitor how your dog is responding to treatment.

Recovery and Management of Seborrhea in Dogs

Recovery and management depend on the cause of the seborrhea. If a primary cause of seborrhea can be found, managing the primary disease is key.

It can take several weeks for the signs of seborrhea to resolve, and the primary disease-causing seborrhea will need to be managed for life.

It is also important to understand that once seborrhea is present, abnormal keratin placement in the skin will continue to occur.

Using anti-seborrheic shampoos and ear cleaners on a schedule recommended by your vet for the rest of your dogs life helps to decrease keratin buildup and prevent infections.

If your dog gets itchier or develops skin lesions, schedule an appointment with your veterinarian as soon as possible.

Management of seborrhea often requires a lifelong routine of bathing and ear cleaning, but with consistent treatment, your dog can enjoy a good quality of life.

Seborrhea in Dogs FAQs

How can I treat my dog's seborrhea at home?

After seeing a vet to confirm your dogs diagnosis, you can treat seborrhea at home by using an anti-seborrheic shampoo containing coal tar and salicylic acid.

Home treatment also includes bathing your dog every 2 to 7 days on a schedule set by your vet. You will also clean your dogs ears with a medicated ear cleaner every 2 to 3 days.

If an underlying health issue is causing your dogs seborrhea, youll need to follow all treatment protocols for that illness to ensure the seborrhea is properly managed.

If your dogs seborrhea is not improving, however, take them to the veterinarian. They might have developed bacterial and yeast infections of the skin and ears that require a prescription medication.