The terms 'eczema' and dermatitis are used interchangeably to describe a range of skin conditions. Although there are several broad categories of eczema, they all result in the skin becoming dry, inflamed, sore and itchy and they all have a constellation of symptoms in common. For some people it is a minor problem, affecting only a small area of skin, whereas for others it can be a major problem affecting large areas of the body and making normal activities difficult. Adult seborrhoeic eczema usually affects adults aged between 20 and 40 years. It is more common in men than in women.
Dandruff is a mild form of seborrhoeic eczema.
Severe seborrhoeic eczema occurs when the scalp scales heavily, the skin beneath becomes red and itchy and the rash spreads on to the face and neck. Patients find that itching is the most distressing feature of the condition and the 'itch-scratch cycle' often plays an important part. Adult seborrhoeic eczema is associated with the presence of the yeast, pityrosporum ovale. Like most yeasts it thrives in warm, moist areas and in sites where a lot of sebum is produced. When the amount of yeast on the skin is reduced, the condition often improves.