Current Management of Scalp Psoriasis

Lyn Guenther, MD, FRCPC, FAAD


Skin Therapy Letter. 2015;20(3) 

In This Article

Topical Therapy

Topical steroids are the most commonly prescribed scalp treatments.[4] They are more efficacious than calcipotriol, coal tar and tazarotene.[3] The scalp is relatively resistant to atrophy induced by topical steroids.[3]

Clobetasol propionate (CP) in various formulations appears to be highly efficacious for scalp psoriasis. In a vehicle-controlled, randomized, double-blind study, after 4 weeks of twice daily application, 85% of patients on CP spray were clear/almost clear compared to 13% on vehicle (p<0.001).[5] Another study showed that CP 0.05% solution was superior to 0.05% betamethasone dipropionate solution.[6] In another study involving 142 individuals with scalp psoriasis, after 4 weeks, CP 0.05% shampoo was more effective than vehicle in reducing total severity score (p<0.001) and 42.1% treated with CP were clear/almost clear compared to 2.1% in the vehicle arm.[7] After an initial daily treatment for 4 weeks, twice weekly maintenance use of this shampoo over 6 months decreased the median time to first relapse (141 days vs. 30.5 days for vehicle, p<0.0001).[8]

The formulation of the topical steroid can make a difference. Foams have the following cosmetic advantages including drying quickly, easy application, and minimal residue after application.[9] In addition, the human cadaver skin model showed greater absorption of CP foam than solution, with a more than double peak rate.[10] In a 14-day study of 26 patients with moderateto- severe psoriasis involving >20% body surface area (BSA), both the CP foam and CP ointment caused similar reversible hypothalamic-pituitary-adrenal (HPA) axis suppression (3 in each group) as has been noted with other class I topical corticosteroids.[10] In a double-blind study involving 188 adults with moderate-to-severe scalp psoriasis, greater reduction in scaling was noted at day 15 with CP (Olux®) foam than with CP solution (p=0.0142); the difference was maintained over the next 14 days despite no additional treatment.[10] Seventy-four percent on CP foam, 63% on CP solution, and 4% and 10% in the placebo groups were clear/almost clear after 14 days of treatment.[10]

Similarly, in the human cadaver skin study, after 12 hours, the bioavailability of betamethasone valerate (BMV) was 300% greater with the foam than the lotion.[11] However, a study in atopic dermatitis in which the foam was applied to 30% or more of BSA showed that BMV foam had little propensity to induce hypothalamic-pituitary axis suppression.[11] In a twice daily 4 week study comparing BMV 0.12% (Luxiq®) foam to BMV lotion, placebo foam and placebo lotion, 72% on BMV foam were clear/almost clear compared to 47% on BMV lotion, and 21% on placebo foam (p<0.05).[11] In a cross-over study involving 210 patients, 88% on BMV foam were clear/almost clear compared to 66% on standard therapy [other topical steroids in 55% of cases [mometasone (70%), betamethasone dipropionate (25%), BMV (3%), and hydrocortisone butyrate (2%)], or calcipotriol lotion in 45% of cases; p<.001].[12] Feldman et al found similar efficacy between once and twice daily BMV foam in the treatment of scalp psoriasis, suggesting that once daily application should be sufficient.[13]

Vitamin D Derivatives

Vitamin D derivatives may cause irritation, but do not cause atrophy.[3] It takes longer to see optimal improvement with vitamin D derivatives (8 weeks) than with steroids (2–3 weeks).[14] In a large (n=3396) observational study of scalp psoriasis, 80% of individuals treated with calcipotriol solution had 'good' or 'very good' improvement after 8 weeks.[15] One study showed similar efficacy between calcipotriol solution and BMV 1% lotion,[16] although in another study involving 474 patients with scalp psoriasis, more patients (75%) were clear or markedly improved with BMV 0.1% solution than with calcipotriol 50 mcg/ml solution (58%, p<0.001) and there was a greater reduction in the total sign score (61% and 45% respectively, p<0.001).[17] An additional study showed that calcipotriol solution was also inferior to clobetasol propionate shampoo.[18]

Vitamin D/steroid combination: Dovobet® gel (formerly Xamiol®; also called Daivobet® and Taclonex®) contains calcipotriol 0.005% and betamethasone dipropionate 0.05%.[4] It has a fast onset of action and is superior to its individual ingredients,[4] and calcipotriol scalp solution.[19] More than twice as many patients treated with Dovobet® gel (68.6% vs. 31.4% on calcipotriol scalp solution) had absent/very mild disease after 8 weeks of use.19 Absent or very mild disease is achieved by approximately 60% of patients after just 2 weeks of therapy and 70% after 8 weeks.[4] Dovobet® gel is efficacious for very severe scalp psoriasis. After 8 weeks, 36.4% who had very severe disease at baseline, demonstrated absent/very mild disease compared to none treated with calcipotriol solution.[19]

Two long-term 52-week studies showed that Dovobet® gel is efficacious and well tolerated.[20,21] Absent/very mild/mild disease was noted in 92.3% of visits with Dovobet® gel vs. 80% with calcipotriol in the first study, while in the second study, the median number of visits with clear/minimal/mild disease was 100%.

Dovobet® gel is well tolerated with no reports of atrophy, striae, purpura, or significant changes in serum calcium in trials.[4] Some patients, however, have had difficulty removing Dovobet® gel from their hair. Application of shampoo, particularly a clarifying shampoo, to dry hair where Dovobet® gel was applied, prior to entering the shower and wetting the hair, aids significantly in the removal of gel.

Other Topical Treatments

Due to its keratolytic effect, salicylic acid may enhance penetration of topical corticosteroids.[3] The National Psoriasis Foundation recommends tazarotene as first-line therapy based on its efficacy off the scalp.[3] Scalp studies are lacking, but the author has successfully used the gel formulation in resistant cases.

Topical Shampoos Other Than Steroid Shampoos

Tar and imidazole antifungal shampoos have modest, at best, efficacy in scalp psoriasis.[22] In an 8-week randomized, open-label study involving 475 patients, a 1% coal tar/1% coconut oil/0.5% salicylic acid shampoo was found to be inferior to calcipotriol (p<0.001). Tar's malodor, hair staining and drying, poor efficacy and carcinogenicity limit its use.[3,22] Imidazole antifungals have been tried since pityrosporon overgrowth has been associated with psoriasis, however, not all studies have shown efficacy.[22]