• Reassure the person that seborrhoeic dermatitis is not caused by lack of cleanliness or excessive dryness of the skin, and is not transmissable.
• Explain that treatment cannot cure seborrhoeic dermatitis but can control it. Symptoms often recur after treatment has stopped.
• Avoid using cosmetic products that contain alcohol.
• Avoid using soap and shaving cream on the face if they cause irritation. Advise the use of non-greasy emollients or emollient soap substitutes.
• A diet rich in yeast-containing products will not affect the disease. If the person has known dietary triggers, these should be avoided, and if the diet is generally poor, advise an improved diet.
• Advise stress reduction, if possible.

In depth

• Remove thick crusts or scales on the scalp before using an antifungal shampoo. Removal of crusts can be achieved by:
• Applying warm mineral or olive oil to the scalp for several hours, then washing with a detergent or coal tar shampoo, or
• Application of a keratolytic preparation (e.g. salicylic acid) or coal tar–keratolytic preparation.
• Prescribe ketoconazole 2% shampoo if it has not been tried already. Selenium sulphide shampoo may be used as an alternative.
• If ketoconazole or selenium sulphide is not acceptable to the person, treat with anti-dandruff shampoos (e.g. containing coal tar or salicylic acid) which are available over-the-counter, after confirming that they have not been tried already. Shampoo can also be applied to the beard area.
• For adults with severe itching, add a potent topical corticosteroid scalp application, such as betamethasone valerate 0.1%, hydrocortisone butyrate 0.1%, or mometasone furoate 0.1%. Try 4–6 weeks of treatment (to the scalp, not the beard). If symptoms have not resolved after this time, seek specialist advice, or sooner if response to treatment is poor.
• Once symptoms are under control, the frequency of shampooing with medicated shampoos may be reduced or stopped.

In depth

• If relapse is a problem, advise use of an antifungal shampoo once a week, or once every other week, or according to the manufacturer's instructions.
• Topical corticosteroids are not appropriate for continuous long-term use, and their use as maintenance treatment is not recommended.

In depth

• Routine follow up is not usually required.
• Advise the person to seek further medical advice if:
• Response to treatment is poor.
• Symptoms worsen despite treatment.
• Signs of infection (e.g. crusting, oozing, bleeding) develop.

In depth

• Consider referral to a dermatologist if there is:
• Diagnostic uncertainty.
• Failure to respond to routine treatment.
• Severe or widespread seborrhoeic dermatitis.

In depth