What is Seborrhoeic Dermatitis?
Seborrhoeic dermatitis is a chronic inflammatory skin condition that mainly affects hiar bearing areas rich in oil glands, such as the scalp, face, and chest. It causes red, flaky, greasy patches that may be itchy or sore.
Who gets seborrhoeic dermatitis?
Seborrhoeic dermatitis can occur at any age. It is common in babies and infants (known as ‘cradle cap’) and adults, particularly males. It is more common in people with oily skin and may be more severe in those with neurological or immune conditions.
What causes seborrhoeic dermatitis?
The exact cause is unknown, but it is thought to involve an overgrowth of a yeast called *Malassezia*, which normally lives on the skin, combined with an inflammatory reaction.
Other contributing factors include:
- Genetics
- Stress
- Immune suppression
- Cold, dry weather
- Hormonal changes
What are the clinical features of seborrhoeic dermatitis?
- Red, scaly patches with greasy or yellowish scale
- Commonly affects the scalp, eyebrows, sides of the nose, and behind the ears
- May cause dandruff
- Can be itchy or cause mild burning
What else could it be?
Seborrheic dermatitis may be confused with the following conditions (and can also coexist with them)
- Psoriasis. Occasionally people have a combination of the two, which is referred to as ‘sebopsoriasis’
- Rosacea. Redness, flushing, pimples and bumps. Different distribution and less scale
- Atopic Dermatitis/irritant or allergic contact dermatitis. Itchy, well defined, less scale
- Systemic Lupus Erythematosus (SLE). The classic ‘butterfly rash’ may have a similar distribution, accompanied by photosensitivity and possible skin involvement elsewhere. Blood tests and a biopsy can help distinguish these
- Periorificial Dermatitis. A nasolabial distribution, with papules, and occasional loose scale. Also possible papules along the eyelid margin.
How is seborrhoeic dermatitis treated?
Babies:
- In babies, cradle cap usually gets better on its own, and treatment if often not necessary, as it rarely causes any symptoms for the baby
- To help the process along, apply a moisturizing cream or ointment in the evening and wash off the following morning with a baby shampoo. You can gently wipe away the scale here with a light brush/comb/clean toothbrush or clean flannel
- Occasionally a mild anti-dandruff shampoo could also be used 1-2 x weekly (these are drying, so more frequent application may cause irritation). Check with your dermatologist for guidance prior to doing this.
Adults:
- General Measures
- Use gentle, non-irritating cleansers
- Avoid harsh soaps and alcohol-based products
- Topical Treatments
- Antifungal creams or shampoos (e.g. ketoconazole, selenium sulfide or zinc pyrithione)
- Keratolytic cleansers, serums or creams (eg containing salicylic acid) may be useful
- Mild topical corticosteroids (often combined with an antifungal) for short-term use
- Anti-inflammatory agents like pimecrolimus or tacrolimus
- Tar preparations may be helpful for the scalp
- Systemic Treatments
- Occasionally a stat dose or short course of an oral antifungal agent may be required
- Low dose isotretinoin can be considered in chronic and refractory cases
What is the outcome of seborrhoeic dermatitis?
This condition is very treatable but can recur. Speak with your dermatologist about establishing an ‘active treatment’ and a ‘maintenance’ plan to keep your skin clear.