Seborrhoeic dermatitis

What are the aims of this leaflet? 

This leaflet has been written to help you understand more about seborrhoeic dermatitis (also known as seborrhoeic eczema). It tells you what it is, what causes it, what can be done about it, and where you can find out more about it. 

What is seborrhoeic dermatitis?

‘Seborrhoeic’ means that the rash affects the greasy, or sebaceous, skin zones such as the face, scalp, centre of the chest and back. ‘Dermatitis’ means that the skin is inflamed and is red, itchy and flaky.

Seborrhoeic dermatitis is slightly more common in men than in women, and occurs in babies, teenagers and in adults, often between the ages of 30 and 40. Dandruff, seborrhoeic dermatitis of the scalp, is very common affecting almost half of all adults, regardless of their age, ethnicity or gender.

Babies can also get a short-lived type of seborrhoeic dermatitis on the scalp, commonly called cradle cap, or in the nappy area. These usually clear after a few months and if there are no symptoms then it may not require treatment. This type of seborrhoeic dermatitis should not be confused with the condition present in adults. When seborrheic dermatitis occurs in babies in the nappy area, it is important to remember that this is entirely separate from the ‘nappy rash’ that can arise in some babies from prolonged contact with soiled nappies.

What causes seborrhoeic dermatitis ?

The cause of seborrhoeic dermatitis is thought to involve many factors and is still being researched. A harmless yeast, Malassezia, is present on normal skin but in seborrheic dermatitis is found in higher amounts. Current thinking is that abnormalities in the skin barrier and increased sensitivity to oleic acid produced by Malassezia result in inflammation causing seborrhoeic dermatitis. The yeast that is present on the skin is not the same as the yeasts that cause thrush or those that are present in foods.

Seborrhoeic dermatitis is experienced more frequently in immunocompromised people, such as people living with HIV or neurological disease, such as Parkinson’s disease. However, in the majority of people, seborrhoeic dermatitis is not usually linked to any underlying illness.

Flares of seborrhoeic dermatitis can be triggered by tiredness, stress and cold, dry weather.

Is seborrhoeic dermatitis hereditary?

Studies have shown there may be a genetic susceptibility to seborrhoeic dermatitis which combines with external factors to cause flare ups.

What are the symptoms of seborrhoeic dermatitis?

The symptoms of seborrhoeic dermatitis vary from person to person. Affected areas can be itchy, sore and sensitive with flaking skin. Some people have the rash without any other symptoms.

What does seborrhoeic dermatitis look like?

The severity and appearance of seborrhoeic dermatitis can vary, and the condition can look different depending on the skin type. The skin can appear red, lighter or darker than the surrounding skin with yellow flaking on the surface. It can affect one or two body areas or can be more widespread. lighter or darker than surrounding skin. The most common sites are:

  • The scalp: seborrhoeic dermatitis here ranges from mild flaky skin, dandruff, to inflamed skin with much more scale which can weep.
  • The face: it often affects the eyebrows and creases around the nose and cheeks. The eyelids can also become red, swollen and flaky, called seborrhoeic blepharitis.
  • In and around the ears: some people have inflammation inside the ear canal, in the cup of the ear and behind the ears. The skin can get infected with bacteria which result in oozing and crusting. Inflammation and flaking skin in the ear canal, otitis externa, can cause it to become blocked.
  • The front of the chest and between the shoulder blades: it shows up as well-defined, round, flat sometimes pink or red (or darker in those with darker skin types) areas with yellow scale.
  • In the skin folds: it often affects moist areas such as the skin under the breasts, in the groin, under the arms, or in folds of skin on the abdomen. The skin can be pink and shiny with surface cracks.

How is seborrhoeic dermatitis diagnosed?

The diagnosis is usually made by examining the rash. In most cases this can be done in primary care but in some cases, patients can be referred to see a dermatologist. Although it is not usually necessary to do any tests these can include:

Blood tests: If seborrheic dermatitis is severe or unresponsive to treatment and someone is at risk of HIV, they may be recommended to get an HIV test. This is important as early treatment of HIV reduces the risk of passing it on and improves the health of the affected person.

Skin scrapings: If there is a suspicion of ringworm of the scalp, then skin scrapings can be sent to look for tinea fungus, this is called mycology.

Skin biopsy: A skin biopsy involves taking a sample of skin to examine under a microscope. Seborrhoeic dermatitis can sometimes be difficult to distinguish from other kinds of rashes. If there is any doubt about the diagnosis a skin biopsy may be suggested.

Can seborrhoeic dermatitis be cured?

Currently there is no cure for seborrhoeic dermatitis, and the aim of treatment is to improve or clear the skin. When treatment is stopped it can flare up again (although the form which occurs in babies does often resolve by itself).

How is seborrhoeic dermatitis treated?

There are some general skin care techniques that can help to minimise flare ups as well as specific treatments that you may be prescribed.

General measures: It is recommended that you use gentle soap-free wash on your skin and affected areas when washing. After washing, a light moisturiser can help your skin barrier. If you wear makeup then selecting products that do not block the pores, non-comedogenic, is recommended. Research suggests that fruit consumption may help to reduce flares.

Antifungals: Antifungal medication also reduces the level of yeast on the skin, helping to treat seborrhoeic dermatitis. Antifungal creams and shampoos are commonly prescribed, and they can safely be used on a long-term basis. Examples include clotrimazole, miconazole, ketoconazole and nystatin which can be available as creams or shampoos. Occasionally, if the rash is widespread or resistant to treatment your doctor may suggest a short course of an oral antifungal medication.

Anti-inflammatory: If the skin is inflamed then anti-inflammatory creams or scalp treatments may be prescribed along with an antifungal treatment. Mild topical corticosteroid can be applied for short periods and can be creams, gels, ointments or scalp lotions. Topical calcineurin inhibitors are newer treatments that do not contain steroids and are safer to use for longer periods. Whilst they can be effective, they are not licensed for seborrheic dermatitis. Your doctor will advise you on the treatment that best suits your needs.

Keratolytics: If you have thick areas of scale, especially over the scalp then you may be prescribed a treatment to help remove this. These can contain coconut oil and salicylic acid. This helps other treatments to penetrate the skin better and so they should be used before other treatments.

How is treatment used?

The treatments described below are not suitable for seborrhoeic dermatitis in babies, which resolves on its own within a few months.

Treatment is usually needed on a long-term basis, though sometimes it is possible to take a break, if your doctor recommends it. The choice depends on which areas of the body are affected and whether there is a lot of irritation.

  • In the scalp: medicated, anti-dandruff shampoos containing agents such as zinc pyrithione, selenium sulphide or ketoconazole can be used regularly. For best results, massage into the scalp, then wait 5-10 minutes before rinsing. If a descaling preparation is prescribed this should be first and left in for several hours, or even overnight This can be messy, but it usually works well. If irritation is troublesome, your doctor may prescribe a steroid scalp treatment for occasional use.
  • The body: washing affected areas on your body with an antifungal shampoo may also help. Lather it up and leave the shampoo on for 5 minutes before rinsing it off.
  • In the ear canals: medicated eardrops may help. Do not clean the ears with cotton buds as this causes more irritation.
  • On the eyelids: carefully cleaning between the lashes with an eyelid cleanser that is not irritating, helps to lift skin flakes and reduce inflammation.

Once the skin or scalp is clear, continue using an antifungal shampoo once or twice a week to reduce the chance of the rash coming back.

Where can I get more information about it?

Please note that the BAD provides web links to additional resources to help people access a range of information about their treatment or skin condition. The views expressed in these external resources may not be shared by the BAD or its members. The BAD has no control of and does not endorse the content of external links.

This leaflet aims to provide accurate information about the subject and is a consensus of the views held by representatives of the British Association of Dermatologists: individual patient circumstances may differ, which might alter both the advice and course of therapy given to you by your doctor.

This leaflet has been assessed for readability by the British Association of Dermatologists’ Patient Information Lay Review Panel





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