Seborrheic dermatitis is a common, inflammatory skin condition that causes flaky, white to yellowish scales to form on oily areas such as the scalp, face or inside the ear. It can occur with or without reddened skin.A.D.A.M.

Causes, incidence, and risk factors

The exact cause of  seborrheic dermatitis is unknown. Doctors think it may be due to a combination hormone levels, weakened immune system, lack of certain nutrients, or nervous system problems. Irritation from a yeast called Malassezia may also lead to this condition. Seborrheic dermatitis appears to run in families.

Risk factors include:

• Stress or fatigue
• Weather extremes
• Oily skin, or skin problems such as acne
• Infrequent shampoos or skin cleaning
• Using lotions that contain alcohol
• Obesity
• Neurologic conditions, including Parkinson's disease, head injury or stroke
• Human immunodeficiency virus (HIV)

Symptoms

Seborrheic dermatitis can occur on different body areas. Usually it forms where the skin is oily or greasy. Common areas include the scalp, eyebrows, eyelids, creases of the nose, lips, behind the ears, in the outer ear, and middle of the chest.

In general, symptoms of seborrheic dermatitis include:

• Skin lesions
• Plaques over large area
• Greasy, oily areas of skin
• Skin scales -- white and flaking, or yellowish, oily, and sticky dandruff
• Itching -- may become more itchy if infected
• Mild redness
• Hair loss

Signs and tests

Diagnosis is based on appearance and location of the skin lesions. Further tests, such as skin biopsy, are rarely needed.

Treatment

Flaking and dryness can be treated with over-the-counter dandruff or medicated shampoos. You can buy these at the drugstore without a prescription. Look for a product that says on the label it treats seborrheic dermatitis. Such products contain ingredients such as salicylic acid, coal tar, zinc, resorcin, ketoconazole, or selenium sulfide. Use the shampoo according to label instructions.

Shampoos or lotions containing selenium, ketoconazole, or corticosteroids may be prescribed for severe cases. To apply shampoos, part the hair into small sections, apply to a small area at a time, and massage into the skin. If on face or chest, apply medicated lotion twice per day. Recently, creams classified as topical immune modulators are being used.

For severe cases, your health care provider will likely prescribe a shampoo or lotion containing a stronger dose of selenium sulfide, ketoconazole, or corticosteroid. A cream that contains an immunomodulator may be prescribed. This medicine suppresses the immune system to treat inflammation.

It is thought that sunlight improves seborrheic dermatitis. In some persons, the condition gets better in the summer, especially after outdoor activities.

Expectations (prognosis)

Seborrheic dermatitis is a chronic (life-long) condition that comes and goes and can be controlled with treatment. Severity of seborrheic dermatitis can be lessened by controlling risk factors and paying careful attention to skin care.

Complications

• Psychological distress, low self esteem, embarrassment
• Secondary bacterial or fungal infections

Calling your health care provider

Call for an appointment with your health care provider if seborrheic dermatitis symptoms do not respond to self-care or over-the-counter treatments.

Also call if patches of seborrheic dermatitis drain fluid or pus, form crusts, or become very red or painful.

Prevention

The severity of seborrheic dermatitis can be lessened by controlling the risk factors and by paying careful attention to skin care.

References

1. Habif TP. Clinical Dermatology: A Color Guide to Diagnosis and Therapy. 5th ed. Philadelphia, Pa.: Elsevier Mosby; 2009:chap 8.

Review Date: 5/15/2013.

Reviewed by: Kevin Berman, MD, PhD, Atlanta Center for Dermatologic Disease, Atlanta, GA. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.