Scalp psoriasis may occur in isolation or with any other form of psoriasis. The back of the head is a common site but multiple discrete areas of the scalp or the whole scalp may be affected. Scalp psoriasis is characterised by thick silvery white scale on patches of very red skin. It may extend slightly beyond the hairline. Scalp psoriasis, even though often adequately camouflaged by the hair, is often a source of social embarrassment due to flaking of the scale and severe 'dandruff'. Scalp psoriasis may not cause any symptoms at all or may be extremely itchy. It tends to be a chronic problem, lasting many years.
In very severe cases there may be some temporary mild localised hair loss but scalp psoriasis does not cause permanent balding.
Scalp psoriasis requires slightly different regimes from psoriasis affecting the skin elsewhere. This is due to hair, which makes application of many topical products difficult and protects the scalp from the effects of ultraviolet light. Unfortunately, many scalp treatments for scalp psoriasis are messy and smelly. Most treatments will need to be used regularly for several weeks before a benefit is seen.
Special medicated shampoos can be purchased from the chemist.
Coal tar shampoos are suitable for most patients with scalp psoriasis
Ketoconazole shampoo is effective for dandruff, seborrhoeic dermatitis and sebopsoriasis
The shampoos work best if rubbed into the scalp well, and left in for 5 or 10 minutes and then reapplied. They are safe for daily use but may irritate if applied more than twice weekly. If you dislike the smell of coal tar, try shampooing again with a favourite brand, and use a conditioner.
More severe cases require leave-on scalp applications.
Alcohol-based topical steroid and calcipotriol lotions can reduce itch but don't lift scale very well. Use topical steroids intermittently; overuse results in more extensive and severe psoriasis.
Salicylic acid and coal tar creams work much better, but are messy. Coconut compound ointment is a combination of coal tar, salicylic acid and sulphur and seems particularly effective. Leave on for at least an hour and shampoo off later. Most people rub the cream into the plaques at night and wash it off in the morning.
Use the scalp preparation daily at first then as the condition improves, reduce the frequency. Unfortunately in many cases the scale soon builds up again, so the creams may have to be applied regularly to keep the scalp clear.
Cutting hair short helps control scalp psoriasis, probably by making the treatments easier to apply, but is not appealing to everyone.
