What are the treatment options for psoriasis?

How Psoriasis is Treated

Treatment for psoriasis should be selected based on disease severity: topical therapies (corticosteroids combined with vitamin D analogs) for mild disease (<5% body surface area), narrowband UVB phototherapy for moderate-to-severe disease (≥5% BSA), and biologic agents (IL-17, IL-23, or TNF inhibitors) for severe or refractory cases. 1, 2, 3

Disease Severity Classification

• Mild psoriasis is defined as <5% body surface area (BSA) involvement 1, 2, 3
• Moderate-to-severe psoriasis is defined as ≥5% BSA or involvement of vulnerable areas (face, genitals, hands, feet) 2, 3
• Patients with symptomatic psoriasis causing pain, bleeding, or itching should be considered for systemic or phototherapy even if BSA is limited 1, 2, 3
• Quality of life impact (measured by DLQI) should guide treatment intensity regardless of physical extent 1, 3

Treatment Algorithm for Mild Psoriasis (<5% BSA)

First-Line Topical Therapy

• Ultra-high potency (Class I) corticosteroids (clobetasol or halobetasol) are recommended for thick plaques on trunk and extremities, achieving 58-92% improvement rates 2
• Combination therapy with topical corticosteroids plus vitamin D analogs (calcipotriene) enhances efficacy and reduces irritation compared to monotherapy 1, 2, 3
• Low-potency corticosteroids should be applied to facial and intertriginous areas to avoid skin atrophy 2, 3

Alternative Topical Options

• Coal tar preparations are recommended for mild to moderate psoriasis with Level I-II evidence 4
• Calcipotriene foam or calcipotriene plus betamethasone dipropionate gel is recommended for scalp psoriasis for 4-12 weeks 1, 3

Treatment Algorithm for Moderate-to-Severe Psoriasis (≥5% BSA)

First-Line: Phototherapy

• Narrowband UVB is recommended as first-line phototherapy, with treatments given no more frequently than every 48 hours 2
• Courses typically last 8-10 weeks, with successive doses increased by 40% if no erythema, 20% if slight erythema, or held at same exposure if more than slight erythema 2
• PUVA (psoralen plus UVA) is an alternative phototherapy option 1, 3

Second-Line: Traditional Systemic Agents

• Methotrexate is recommended as first-line systemic therapy, starting at 15 mg weekly, maximum 25-30 mg weekly, with response within 2 weeks 2
  • Requires baseline and regular monitoring of full blood count, liver function tests, and serum creatinine 3
• Cyclosporine provides rapid response at 2.5-5 mg/kg daily, with response within 3 weeks 2
  • Requires baseline and regular monitoring of blood pressure, renal function, and lipid profile 3
• Acitretin is another traditional systemic option for moderate-to-severe disease 1, 3

Third-Line: Biologic Agents

• IL-17 inhibitors (secukinumab, ixekizumab, brodalumab), IL-23 inhibitors (guselkumab, tildrakizumab, risankizumab), and IL-12/23 inhibitors (ustekinumab) are recommended as third-line treatment 1, 3, 5
• TNF inhibitors (adalimumab, etanercept, infliximab, certolizumab) are effective for both skin and joint symptoms 1, 6, 5
• The American Academy of Dermatology-National Psoriasis Foundation guidelines recommend biologics as an option for first-line treatment of moderate to severe plaque psoriasis because of their efficacy and acceptable safety profiles 5

Combination Therapy Strategies

• Adding ultra-high potency (Class I) topical corticosteroid to standard dose etanercept for 12 weeks is recommended for moderate to severe psoriasis (Level I evidence) 4
• Adding calcipotriene/betamethasone to standard dose adalimumab for 16 weeks is recommended to accelerate clearance of psoriatic plaques 4
• Adding topical calcipotriene to standard dose methotrexate therapy is recommended for moderate to severe psoriasis (Level I evidence) 4
• All topical corticosteroids can be used in combination with any biologics for moderate to severe psoriasis 4

Special Considerations for Psoriatic Arthritis

• NSAIDs are recommended for mild joint symptoms 4, 3
• DMARDs (methotrexate, sulfasalazine, leflunomide) are recommended for moderate-to-severe joint involvement 4, 3
• TNF inhibitors are recommended for inadequate response to at least one DMARD 4, 3
• For severe enthesitis that has failed therapies for mild and moderate disease, a TNF inhibitor should be considered 4

Critical Safety Warnings

• Systemic corticosteroids should be avoided in psoriasis as they cause disease flare during taper 1, 2, 3
• Long-term use of potent topical corticosteroids can cause skin atrophy, striae, and telangiectasia 1, 3
• All commonly used systemic agents are absolutely contraindicated in pregnancy, with risks explained to women of childbearing age and ensuring contraception 2, 3
• For adalimumab and other TNF blockers, there is an increased risk of serious infections (including tuberculosis, bacterial sepsis, invasive fungal infections) and malignancy (including lymphoma) 6
• Perform test for latent TB before starting TNF blockers; if positive, start treatment for TB prior to starting therapy 6

Common Pitfalls to Avoid

• Do not apply vitamin D analogs before phototherapy as this may cause inactivation 1
• Commercial sunbeds are rarely effective for psoriasis and may cause premature skin aging and increased skin fragility 3
• Avoid combination of multiple systemic agents as this may increase risk of toxicity 1
• Drugs that may precipitate or worsen psoriasis include alcohol, beta-blockers, NSAIDs, lithium, chloroquine, and mepacrine 1

Maintenance and Rotational Strategies

• Maintenance therapy with intermittent topical steroid application or vitamin D analogs can help prolong remission 3
• Rotational therapy (switching between treatment modalities every 1-2 years) may minimize cumulative toxicity of individual treatments 1, 2