What is the management for psoriasis?

Management of Psoriasis

For mild psoriasis (<5% body surface area), initiate treatment with high-potency topical corticosteroids (clobetasol 0.05% or betamethasone dipropionate 0.05%) combined with calcipotriol twice daily for 2-4 weeks maximum, achieving 58-92% clearance rates. 1, 2

Topical Therapy Algorithm for Mild Disease

Start with combination therapy rather than monotherapy, as the synergistic effect of corticosteroids plus vitamin D analogs (calcipotriol) demonstrates superior efficacy compared to either agent alone. 1, 3

Application Strategy by Body Region:

• Thick plaques on trunk/extremities: Apply clobetasol propionate 0.05% or betamethasone dipropionate 0.05% twice daily for maximum 2-4 weeks, combined with calcipotriol 1, 2

• Sensitive areas (face, genitals, intertriginous regions): Use low-potency corticosteroids or topical calcineurin inhibitors to minimize atrophy risk 1

• Body plaques requiring enhanced efficacy: Add tazarotene to moderate-to-high potency corticosteroids to reduce irritation while enhancing treatment response 1, 3

Critical Safety Monitoring for Topical Therapy:

• Conduct clinical review every 4 weeks during active treatment with no unsupervised repeat prescriptions for high-potency agents 2
• Limit moderate-potency corticosteroid use to maximum 100g per month 2
• Implement periods each year when alternative treatments are employed to prevent tachyphylaxis 4

Common pitfall: Perceived "tachyphylaxis" to topical corticosteroids is usually due to poor patient adherence rather than true receptor down-regulation—address compliance issues before switching therapies. 1, 3

When to Escalate to Systemic Therapy

Escalate to systemic treatment when body surface area exceeds 5%, after inadequate response to optimized topical therapy for 8 weeks, or with repeated hospital admissions for topical treatment. 1, 2

Additional indications include: 4

• Extensive chronic plaque psoriasis in elderly or infirm patients
• Generalized pustular or erythrodermic psoriasis
• Severe psoriatic arthropathy

Systemic Therapy Selection

Photochemotherapy (PUVA) is the least toxic systemic agent and should be considered first-line systemic treatment. 4, 1

PUVA Protocol:

• Start at 70% of minimum phototoxic dose (determined at 72 hours) 4, 1
• Increase successive doses by 40% of the preceding dose if no erythema develops 4, 1
• Expected response time: 4 weeks 4
• Requires eye examination before treatment and UV eye protection during therapy 4

Conventional Systemic Agents:

The 2020 AAD-NPF guidelines provide detailed guidance on methotrexate, which has been FDA-approved since 1972 and works through multiple mechanisms including inhibition of dihydrofolate reductase and increasing endogenous adenosine. 4

Methotrexate considerations: 4

• Response time: 2 weeks
• Requires pretreatment assessment: complete blood count, liver function tests, serum creatinine
• Absolute contraindications: pregnancy, breastfeeding, wish to father children, significant hepatic damage, anemia, leucopenia, thrombocytopenia
• Mandatory contraception for both men and women during treatment

Other systemic options with response times: 4

• Cyclosporin: 3 weeks (monitor blood pressure and serum creatinine)
• Acitretin (etretinate): 6 weeks (contraception required for 2 years after stopping in women)
• Hydroxyurea: 4 weeks
• Azathioprine: 4 weeks

Biologic Therapy for Moderate-to-Severe Disease

Adalimumab (TNF-α inhibitor) achieves treatment goals in 68.2-79.3% of patients by week 16 and can be combined with methotrexate or topical high-potency corticosteroids. 1

Critical Safety Screening Before Biologics:

Per FDA labeling, screen for: 5

• Active or latent tuberculosis
• Hepatitis B
• Fungal infections (histoplasmosis, coccidioidomycosis, blastomycosis in endemic areas)
• Previous malignancy history

Important safety warning: TNF-blockers including adalimumab increase risk of serious infections and malignancies, including lymphoma and hepatosplenic T-cell lymphoma (particularly in young males receiving concomitant azathioprine or 6-mercaptopurine). 5

Special Considerations for Pustular Psoriasis

For generalized pustular psoriasis, infliximab demonstrates rapid and often complete disease clearance and should be considered first-line biologic therapy at standard dosing of 5 mg/kg infused at weeks 0,2, and 6, then every 8 weeks thereafter. 1

Alternative option: Acitretin can be used for pustular psoriasis 1

Medications to ABSOLUTELY AVOID

Never prescribe systemic corticosteroids for psoriasis—they precipitate erythrodermic psoriasis, generalized pustular psoriasis, or very unstable disease upon discontinuation. 1, 3

Other medications that cause severe, potentially fatal psoriasis deterioration: 1, 3

• Lithium
• Chloroquine
• Mepacrine

Alternative Topical Options When First-Line Fails

If a patient fails to respond to one topical agent, trial alternative topical agents before escalating to systemic therapy, as patients may respond to different formulations. 4, 1, 3

Coal Tar:

• Start with 0.5-1.0% crude coal tar in petroleum jelly 4
• Increase concentration every few days to maximum 10% 4
• Cruder extracts are messier but more effective than refined products 4

Dithranol (Anthralin):

• Start at 0.1-0.25% concentration 4
• Increase in doubling concentrations as tolerated 4
• Short contact mode: leave on skin for only 15-45 minutes every 24 hours 4
• Exercise great care on sensitive sites (face, flexures, genitalia) 4

Occlusive Dressing Technique for Recalcitrant Lesions

Per FDA labeling for triamcinolone, occlusive dressings may be used for psoriasis or other recalcitrant conditions: 6

• Apply cream and cover with pliable nonporous film, sealing edges
• Apply in evening and remove in morning (12-hour occlusion)
• Reapply without occlusion during the day
• Discontinue if infection develops 6

Pregnancy Considerations

For moderate-to-severe psoriasis in pregnant women, narrow-band UVB phototherapy is first-line, avoiding all systemic agents. 2

Methotrexate is absolutely contraindicated during pregnancy and breastfeeding, and conception must be avoided for at least one menstrual cycle after stopping in women. 2