Seborrheic dermatitis

What is it?

Seborrheic dermatitis is a form of skin inflammation (dermatitis) that causes a red, oily, flaking skin rash in areas of the body where glands in the skin called sebaceous glands are most abundant — the scalp, face and groin. In infants, it primarily affects the scalp, where it is called cradle cap. The causes of seborrheic dermatitis are unclear, but yeast may be involved in some cases.

Although doctors recognize that seborrheic dermatitis occurs in skin areas that have many sebaceous glands, they still do not know exactly why it develops there. It is thought that a tiny yeast may play a role in seborrheic dermatitis. Seborrheic dermatitis is a common skin disorder that affects people who often have no other health problems.

Symptoms

In infants, seborrheic dermatitis appears as a scaly redness that usually is not itchy or uncomfortable. In some babies, it affects only the scalp (cradle cap), but in others, it also involves the neck creases, armpits or groin.

In adults and adolescents, seborrheic dermatitis may affect only the scalp, appearing as either patchy or diffuse areas of redness and flaking. Other skin areas commonly affected include the eyebrows, eyelids, forehead, nose creases, outer ear, chest, underarms, or groin. Although some adults and adolescents feel an itchy or burning irritation in areas of seborrheic dermatitis, others don't have any discomfort. In some people, seborrheic dermatitis flare-ups are triggered by stress.

Diagnosis

Your doctor usually can diagnose seborrheic dermatitis by a simple physical examination.

Expected duration

In infants, seborrheic dermatitis typically is worst during the first year of life. It usually disappears on its own as the child grows, and it may return during the teenage years. In adults and adolescents, seborrheic dermatitis tends to be a chronic condition that comes and goes over many years.

Prevention

Because doctors do not know what causes seborrheic dermatitis, there is no way to prevent it. However, symptoms can be controlled with effective treatment.

Treatment

If you have an infant with cradle cap, your doctor may suggest applying baby oil to soften the scale, followed by shampooing with a mild baby shampoo to gently remove the scale. If this doesn't help, your doctor may recommend an anti-seborrheic dermatitis shampoo. For skin areas outside the scalp, your doctor may prescribe hydrocortisone or an anti-yeast cream, because yeast sometimes can trigger seborrheic dermatitis.

If you are an adult with scalp seborrheic dermatitis, your doctor may suggest a shampoo containing selenium sulfide or zinc pyrithione. Your doctor also may prescribe corticosteroid cream and shampoo containing ketoconazole. For other skin areas, hydrocortisone or anti-yeast cream can be rubbed directly into seborrheic dermatitis patches.

For adults with persistent seborrheic dermatitis, treatment with oral itraconazole 200 mg daily for 7 days, and then the same dose for the first 2 days of each month can be very effective. Usually the treatment is only needed for 3 months.

When to call a professional

Call your doctor if you have not been able to control your seborrheic dermatitis with shampoos and creams. Remember, the goal is control. There is no cure.

Prognosis

Cradle cap typically disappears on its own as a child grows. Other forms of seborrheic dermatitis usually respond very well to topical treatment with medicated shampoos and/or creams. When needed, an oral anti-fungal medicine can be very effective.

Additional info

American Academy of Dermatology
https://www.aad.org/