Scalp Psoriasis: Treatment Ladder from Topicals to Biologics

Scalp psoriasis affects ~50% of plaque psoriasis patients. Thick scale, hair-bearing skin, and sebum require tailored approaches.

1. Topicals (First-Line)

• Corticosteroids: Solutions, foams, sprays, oils (penetrate hair better than creams). Potent (clobetasol) for flare; mid-potency for maintenance. Limit to 2-4 weeks continuous.
• Vitamin D analogs: Calcipotriene 0.005% solution/foam. Slows keratinocyte proliferation. Combine with steroid for synergy.
• Tazarotene 0.05-0.1% gel: Retinoid; irritant – start alternate nights.
• Coal tar 2-10% shampoo: Anti-inflammatory, antiproliferative. Odor/staining.
• Salicylic acid 3-6%: Keratolytic; enhances penetration of other topicals.

2. Phototherapy

• UVB comb/handheld device for scalp.
• Excimer laser (308 nm) for resistant plaques.
• Requires 2-3x/week visits; hair blocks UV – part hair or use comb.

3. Systemics (Moderate-Severe, BSA >5-10% or QOL impact)

• Methotrexate (15-25 mg/week + folic acid)
• Cyclosporine (short-term bridge)
• Apremilast (PDE4 inhibitor)
• Biologics: TNF-α (adalimumab, etanercept), IL-17 (secukinumab, ixekizumab), IL-23 (guselkumab, risankizumab) – high efficacy, scalp-specific data.

4. Adjunctive/Supportive

• Gentle shampoo (tar, salicylic acid, zinc pyrithione).
• Scale removal: oil soak (coconut, mineral) → gentle combing → medicated shampoo.
• Avoid triggers: stress, alcohol, smoking, trauma (Koebner).
• Moisturize scalp (ointments at night).

Treatment Algorithm

Topicals → topicals + phototherapy → systemics/biologics. Shared decision-making: efficacy, safety, cost, patient preference.