What are the primary care treatment options for scalp psoriasis?

Primary Care Treatment for Scalp Psoriasis

First-Line Treatment Recommendation

Start with a combination product containing calcipotriene plus betamethasone dipropionate in foam or gel formulation applied once daily, as this achieves 69-74% clear or almost clear status and is more effective than either agent alone. 1

Treatment Algorithm by Severity

Mild to Moderate Scalp Psoriasis

• Initiate calcipotriene 0.005% plus betamethasone dipropionate 0.064% foam or gel once daily for 4-12 weeks 1
• This combination is safe for up to 52 weeks with no serious adverse events including striae or HPA axis suppression 1
• Vehicle formulations (solutions, foams, shampoos) are superior to creams or ointments for scalp application due to better penetration through hair and improved adherence 1, 2

Moderate to Severe Scalp Psoriasis

• Use high-potency topical corticosteroids (class 1-2) such as clobetasol propionate 0.05% solution, foam, or spray 1
• Apply twice daily for 2 weeks maximum initially, achieving 81% of patients with 50% or better clearing 3
• Maximum weekly dose should not exceed 50g 3
• After initial control, taper gradually to once daily, then alternate days, then twice weekly to prevent rebound 1, 3

Alternative Monotherapy Options

Vitamin D Analogue Alone

• Calcipotriene foam 0.005% achieves 40.9% clear or almost clear status after 8 weeks 1
• Important caveat: Vitamin D analogues show efficacy at 8 weeks but not at 4 weeks, so plan for longer treatment duration 1
• Apply calcipotriene after phototherapy if using both, as UVA radiation decreases its concentration 1

Corticosteroid Monotherapy

• Class 3-7 corticosteroids for mild to moderate disease 1
• Class 1-2 (high-potency) for moderate to severe disease 1
• Use for minimum of 4 weeks initially; longer use (>12 weeks) requires careful physician supervision 1
• Betamethasone valerate foam (class IV) shows 72% improvement versus 47% with placebo 1

Adjunctive Therapy

• Ketoconazole shampoos reduce risk of scalp folliculitis and serve as effective alternatives 2
• Coal tar-containing shampoos can be combined with corticosteroids for long-term management 1

Critical Safety Monitoring

Common Adverse Effects

• Burning and stinging sensation (most frequent with clobetasol solution, occurring in 29 of 294 patients) 4
• Folliculitis (most common with scalp application) 3, 4
• Scalp pustules, tingling, itching, tightness 4

Serious Risks to Monitor

• Skin atrophy, striae, telangiectasia with prolonged high-potency corticosteroid use 1, 3
• HPA axis suppression (transient and reversible after 2-week courses) 4
• Tachyphylaxis with extensive use 3
• Never apply clobetasol to face or intertriginous areas due to highest risk for adverse effects 3

When to Escalate to Systemic Therapy

Consider systemic therapy if topical treatment fails after an adequate trial with proper adherence, particularly when there is symptomatic disease or more than minimal impact on quality of life. 1, 2 The European League Against Rheumatism considers scalp psoriasis a "vulnerable area" warranting systemic therapy under these circumstances 1

Pregnancy Considerations

• Most topical psoriasis medications are pregnancy category C 1, 2
• Tazarotene is category X 1
• Counsel women of childbearing potential appropriately before initiating treatment 1, 2

Adherence Optimization

• Poor adherence is common due to inconvenience, time constraints, and messy formulations 1
• Prescribe scalp-specific vehicles (solutions, foams, sprays, shampoos) rather than creams or ointments to maximize compliance 1, 3, 2
• Clobetasol shampoo formulation allows short contact time while maintaining efficacy and minimizing systemic exposure 5