Seborrheic dermatitis

Definition

Seborrheic dermatitis is a common inflammatory skin condition. It 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.

Cradle cap is the term used when seborrheic dermatitis affects the scalp of infants.

Alternative Names

Dandruff; Seborrheic eczema; Cradle cap

Causes

The exact cause of seborrheic dermatitis is unknown. It may be due to a combination of factors:

• Oil gland activity
• Yeasts called Malassezia, which live on the skin, mainly in areas with more oil glands
• Changes in skin barrier function
• Your genes

Risk factors include:

• Stress or fatigue
• Weather extremes
• Oily skin, or skin problems such as acne
• Heavy alcohol use, or using lotions that contain alcohol
• Obesity
• Nervous system disorders, including Parkinson disease, traumatic brain injury, or stroke
• Having HIV/AIDS

Symptoms

Seborrheic dermatitis can occur on different body areas. It often 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 with scales
• 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

Exams and Tests

Diagnosis is based on the 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 or dandruff. Such products contain ingredients such as salicylic acid, coal tar, zinc, resorcinol, ketoconazole, or selenium sulfide. Use the shampoo according to label instructions.

For severe cases, your health care provider will likely prescribe a shampoo, cream, ointment, or lotion containing either a stronger dose of the above medicines or containing any of the following medicines:

• Ketoconazole
• Ciclopirox
• Sodium sulfacetamide
• A corticosteroid
• Tacrolimus or pimecrolimus (medicines that suppress the immune system)

Phototherapy, a medical procedure in which your skin is carefully exposed to ultraviolet light, may be needed.

Sunlight may improve seborrheic dermatitis. In some people, the condition gets better in the summer, especially after outdoor activities.

Outlook (Prognosis)

Seborrheic dermatitis is a chronic (life-long) condition that comes and goes, and it can be controlled with treatment.

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

Possible Complications

The condition may result in:

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

When to Contact a Medical Professional

Call for an appointment with your provider if your symptoms don't 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.

References

American Academy of Dermatology Association website. Seborrheic dermatitis: overview. www.aad.org/public/diseases/a-z/seborrheic-dermatitis-overview. Accessed June 6, 2021.

James WD, Elston DM, Treat JR, Rosenbach MA, Neuhaus IM. Seborrheic dermatitis, psoriasis, recalcitrant palmoplantar eruptions, pustular dermatitis, and erythroderma. In: James WD, Elston DM, Treat JR, Rosenbach MA, Neuhaus IM, eds. Andrews' Diseases of the Skin: Clinical Dermatology. 13th ed. Philadelphia, PA: Elsevier; 2020:chap 10.

Paller AS, Mancini AJ. Eczematous eruptions in childhood. In: Paller AS, Mancini AJ, eds. Paller and Mancini – Hurwitz Clinical Pediatric Dermatology. 6th ed. Philadelphia, PA: Elsevier; 2022:chap 3.