Seborrhoeic dermatitis is an inflammatory scaling of the scalp, face and sometimes other areas
The dermatitis is usually seen only as a dry or greasy diffuse scaling of the scalp (dandruff) with variable itching
Newborns, less than one month old, may develop seborrhoeic dermatitis of the scalp called “cradle cap"
Treatment depends on the severity and location of the illness
This is an inflammatory scaling of the scalp, face and sometimes other areas. In spite of the name of the illness, the composition and flow of the oily substance, sebum, which is secreted by the skin, is usually normal.
Symptoms and signs
Onset in adults is usually gradual. The dermatitis is usually seen only as a dry or greasy diffuse scaling of the scalp with variable itching.
In severe disease, yellow-red scaling papules appear along the hairline, behind the ears, in the outer ear, on the eyebrows, on the bridge of the nose, in the folds of the nose and over the chest bone (sternum). The upper back and skin folds such as the axillae and groin may also be involved.
Seborrhoeic dermatitis may also occur in children up to the age of two years. The most common presentation is in the form of greasy scales on the scalp (cradle cap). This form of dermatitis may be more widespread and involve the diaper area and the rest of the body.
Treatment depends on the severity and location of the illness.
In adults, zinc, sulphur and salicylic acid preparations or tar shampoo should be used daily or every other day until the dermatitis is controlled. It should then be used twice a week.
A corticosteroid lotion can be rubbed into the scalp or other hairy areas until the redness subsides.
Hydrocortisone cream is best for facial areas.
In infants, a mild baby shampoo is used daily and a hydrocortisone cream rubbed in twice a day. For thicker lesions, 10% salicylic acid in mineral oil, or a corticosteroid gel is applied at bedtime to the affected areas. The scalp is shampooed daily until the thick scale is gone.
Salicyclic acid preparations should not be used for longer than one week.
The condition runs a chronic course with relapse and remissions. Seborrhoeic dermatitis in adults is incurable. In infants, spontaneous resolution is the rule.
The prognosis is better than in atopic dermatitis. Very rarely, in infants or adults, the condition may become generalised.
(Reviewed by Prof H.F. Jordaan)