Management of Scalp Psoriasis

Abstract

Scalp psoriasis is a frequent expression of the common skin disease psoriasis, and scaling and itching are the two major complaints. Topical treatments are the mainstay of the treatment of psoriasis of the scalp, with the vehicle as well as the active ingredient relevant to efficacy, tolerability and compliance. Vehicles can be shampoos, lotions, gels, foams, creams and more greasy ointments. Active ingredients are keratolytics, coal tar (liquor carbonis detergens), dithranol, corti-costeroids and vitamin D₃ analogues. Some effect has also been described from topical or systemic imidazole derivatives.

Topical corticosteroids remain the mainstay in the treatment of scalp psoriasis. The effects are rapid, the formulations are patient friendly and the adverse effects seem limited, although no data are available to support safety during prolonged use (more than 4 weeks).

Topical vitamin D₃ analogues have been available for the treatment of psoriasis since 1992. In the lotion formulation in particular, vitamin D₃ analogues are a patient friendly, tolerable and effective alternative to corticosteroids, although the effects are optimal after 8 weeks, in contrast to 2–3 weeks for topical corticosteroids. Facial irritation (often temporary) can also be a disadvantage of vitamin D₃ analogues, although only a small proportion of patients stop treatment for this reason.

All other treatment options for psoriasis, such as tazarotene, phototherapy and systemic treatment with methotrexate, acitretin and cyclosporin are often not indicated or not suitable for treatment of the scalp.

In daily practice, to make a choice from the available therapeutic arsenal for psoriasis, each patient should be examined individually. Deteriorating factors have to be excluded. For scaling, keratolysis is the first step. Subsequently, active treatment can be chosen depending on the clinical picture. When the psoriatic lesions are mainly characterised by inflammation, anti-inflammatory drugs such as topical corticosteroids are indicated. When scaling is the more important clinical feature, vitamin D₃ analogues are indicated.

Generally, intermittently used topical corticosteroids alternating with vitamin D₃ derivatives either combined or not with liquor carbonis detergens containing shampoo is the most suitable treatment for most patients. Because psoriasis capitis is a chronic disease, long term treatment should, in addition to medical advice, also provide patient support and motivation.