Beauty Care Clinic

An itchy scalp is often the first sign of dandruff, seborrhoeic dermatitis or psoriasis. In all three dermatological disorders, the individual skin cells on the scalp grow and divide more rapidly than usual. This results in increased shedding of flattened dead cells, called squames, that get caught on the hair shaft or fall onto clothing. To the naked eye, the squames appear as tiny white flakes which stand out most on dark hair or dark clothing. The appearance of these white flakes should not be interpreted as evidence of scalp dryness or of a poor quality shampoo.

Dandruff, the mildest of the three conditions, can usually be controlled with a shampoo containing zinc pirithione or selenium sulfide. Fortunately, such anti-dandruff shampoos are freely available and widely marketed.

Seborrhoeic dermatitis is more extensive and examination of the scalp may reveal pink or light tan slightly scaly patches varying in size from a few millimetres to several centimetres. These patches cannot usually be felt with the fingertips, which helps to differentiate this condition from psoriasis. Recent research has shown that a yeast known as Pityrosporum ovale may play a role in causing this annoying problem.

Fortunately, this yeast can usually be eradicated by zinc pirithione or selenium sulfide in concentrations usually found in anti-dandruff shampoos. In resistant cases, your dermatologist may need to prescribe a special cream or shampoo to alleviate the problem.

Psoriasis is usually more severe and characterised by thick crusted plaques which can be readily felt with the fingertips. The plaques are common behind the ears and over the back of the scalp just above the nape of the neck. The plaques themselves are bright pink and have a thick crust of silvery scales. Treatment of psoriasis is considerably more complicated than that for dandruff or seborrhoeic dermatitis and is also influenced by the presence or absence of psoriasis elsewhere on the body. In most instances, the dermatologist will prescribe cream to be massaged into the scalp, as well as specialised shampoos. Creams and lotions containing tar are highly effective in the management of psoriasis but unfortunately tend to stain and smell unpleasant. Cortisone creams and lotions are much more pleasant to use but unfortunately are only suitable for mild cases of psoriasis. Furthermore, with continued use these products gradually become less effective. Recent studies overseas have demonstrated the effectiveness of a new vitamin D cream in the management of scalp psoriasis.