What is the first line of treatment for mild to moderate psoriasis?

First-Line Treatment for Mild to Moderate Psoriasis

Topical corticosteroids are the first-line treatment for mild to moderate psoriasis, with moderate to high potency (classes 2-5) corticosteroids generally recommended as initial therapy for adults. 1

Assessment of Disease Severity

• Mild psoriasis is defined as affecting less than 5% of body surface area, being generally asymptomatic, having minimal impact on quality of life, and being amenable to localized therapy 1
• Moderate to severe psoriasis includes cases with more than 5% body surface area affected, symptoms (pain, bleeding, itching), more than minimal impact on quality of life, inadequate response to localized therapy, or involvement of vulnerable areas (face, genitals, hands/feet, nails, scalp, intertriginous areas) 1

Treatment Algorithm for Mild to Moderate Psoriasis

First-Line Therapy:

• For plaque psoriasis not involving intertriginous areas: Class 2-5 (moderate to high potency) topical corticosteroids for up to 4 weeks (Strength of recommendation: A; Level of evidence: I) 1, 2
• For thick, chronic plaques: Class 1 (ultrahigh-potency) corticosteroids may be required 1
• For scalp psoriasis: Class 1-7 topical corticosteroids for a minimum of up to 4 weeks (Strength of recommendation: A; Level of evidence: I) 1
• For facial and intertriginous psoriasis: Lower potency corticosteroids or topical calcineurin inhibitors (tacrolimus 0.1% ointment or pimecrolimus 0.1% cream) 1, 2

Application Frequency:

• Once or twice daily application of topical corticosteroids for 2-4 weeks 1, 3
• After clinical improvement, consider tapering to alternate days and eventually twice weekly to maintain remission 4, 5

Efficacy of Topical Corticosteroids

• Ultrahigh-potency (class 1) corticosteroids show efficacy rates of 58-92% in randomized controlled trials 1, 6
• In a double-blind, vehicle-controlled trial, clobetasol propionate spray 0.05% administered twice daily for 4 weeks was effective in reducing scaling, erythema, plaque elevation, and overall disease severity 6
• Alternate-day application of topical corticosteroids can be as effective as once-daily application in the initial 2 weeks, but by 6 weeks, its efficacy decreases 3

Alternative First-Line Options

• Vitamin D analogues (calcipotriene, calcitriol) are effective for mild to moderate psoriasis, with efficacy noted at 8 weeks but not at 4 weeks 1
• Combination treatments with vitamin D analogues and potent topical corticosteroids from 3 to 52 weeks are more effective than either agent alone 1

Important Considerations and Precautions

• Lower potency corticosteroids should be used on the face, intertriginous areas, and areas susceptible to steroid atrophy 1
• Common local adverse effects include skin atrophy, striae, folliculitis, telangiectasia, and purpura 1, 5
• Use beyond 4 weeks significantly increases risk of both cutaneous side effects and systemic absorption 4, 5
• Use beyond 12 weeks may be considered in certain cases, but only under careful supervision of a physician (Strength of recommendation: C; Level of evidence: III) 1

Treatment of Special Sites

• For scalp psoriasis: Calcipotriene foam for 8 weeks and calcipotriene plus betamethasone dipropionate gel for 4 to 12 weeks are safe and effective 1
• For facial psoriasis: Calcipotriene or tacalcitol ointment combined with hydrocortisone is efficacious 1

By following this treatment algorithm and considering the specific characteristics of the patient's psoriasis (location, severity, previous treatments), topical corticosteroids provide an effective first-line approach for managing mild to moderate psoriasis with good safety when used appropriately.