Topical treatments for psoriasis of the scalp
What are the most effective and safest treatments?
People with chronic plaque psoriasis often have itching with reddish, scaly lesions that are visible and are often embarrassing. Creams, gels, and shampoos are usually tried first, but applying them to the scalp is difficult because of the hair. As psoriasis remains a long-term condition, it is of great importance to know which of the drugs work best and if there are side effects. Many different regimens have been studied for the treatment of scalp psoriasis (antifungals, dithranol, retinoids, vitamin D analogues, corticosteroids, phototherapy, pulsed magnetic fields, Grenz rays, keratolytics, emollients, salicylic acid, coal tar, and tacrolimus) but there is still no evidence-based consensus in the literature to offer guidance to healthcare practitioners or to patients involved in the clinical decision-making.
A team of Cochrane authors based in Germany worked with the Cochrane Skin Group to investigate what are the most effective and safest treatments for psoriasis on the scalp. 59 randomised controlled trials were included, with a total of 11,561 participants. The overall evidence was rated to be of moderate quality.
Corticosteroids, also known as steroids, of high or very high potency are more effective than vitamin D. The combination product of a steroid and vitamin D is of small benefit over steroids alone. The combination product is superior to vitamin D alone. Steroids of moderate, high and very high potency tend to be similarly effective. There is not enough evidence to allow a final conclusion as to whether salicylic acid is of additional benefit in combination with steroids. Few and mostly unreliable data suggest that the efficacy of tar or dithranol preparations is limited. There might not be a difference whether steroids are used once or twice daily.
“Most of the studies that we found were carried out for only 6 months. Psoriasis is a long-term condition, so longer-term assessment studies that measure efficacy, safety and the participants’ quality of life are needed.” said Gabriel Schlager, the lead author of the Cochrane Review. “There are many different options to treat scalp psoriasis. However, given the evidence, clinicians and patients can be assured that for the short-term treatment either a steroid preparation of high or very high potency or a steroid/vitamin D combination have the most benefit with the least adverse events.”
