What are the treatment options for psoriasis?

Psoriasis Treatment Overview

For mild psoriasis (<5% body surface area), start with combination calcipotriene/betamethasone dipropionate once daily for 4-8 weeks, which achieves clear or almost clear status in 48-74% of patients. 1, 2

Disease Severity Classification

• Mild psoriasis is defined as <5% body surface area (BSA) involvement with minimal symptoms 1, 3
• Moderate-to-severe psoriasis is ≥5% BSA, or any symptomatic disease (pain, bleeding, itching), or significant quality of life impact regardless of BSA 1, 3, 2
• Symptomatic patients require systemic or phototherapy even with limited BSA involvement 1, 3, 2

Treatment Algorithm by Severity

Mild Psoriasis: Topical Therapy

First-Line Combination Therapy:

• Apply calcipotriene/betamethasone dipropionate combination product once daily for 4-8 weeks 1, 2
• This combination is more effective than either agent alone and reduces irritation compared to vitamin D analogues alone 1, 4
• Maximum vitamin D analogue use: 100g per week to avoid hypercalcemia 3, 2

Maintenance Strategy After Initial Control:

• Transition to weekend-only high-potency corticosteroid application (twice daily on weekends) with weekday vitamin D analogue therapy (twice daily on weekdays) 3
• This minimizes corticosteroid exposure while maintaining efficacy 3

Site-Specific Modifications:

• Face/intertriginous areas: Use low-potency corticosteroids or calcitriol ointment to prevent skin atrophy 1, 3, 2
• Scalp: Use calcipotriene foam or calcipotriene plus betamethasone dipropionate gel for 4-12 weeks 1, 3, 2
• Trunk/extremities: Use class 2-5 (moderate to high potency) corticosteroids initially 3
• Thick, chronic plaques: Require class 1 (ultrahigh-potency) corticosteroids like clobetasol propionate 0.05% or halobetasol propionate 0.05% 3

Alternative Topical Options:

• Tazarotene 0.1% gel once daily plus medium/high-potency corticosteroid demonstrates synergistic effect and prolongs remission 3
• Coal tar, anthralin, and salicylic acid have varying efficacy but practical limitations (staining, irritation) 1, 3

Moderate-to-Severe Psoriasis: Systemic Therapy

First-Line Options:

Phototherapy:

• Narrowband UVB is first-line for patients with ≥5% BSA or inadequate response to topicals 1, 2, 5
• 308-nm excimer laser allows selective targeting of localized resistant areas 3

Biologic Agents (Preferred for Severe Disease):

• IL-23 inhibitors (guselkumab, tildrakizumab, risankizumab): Target p19 subunit of IL-23 5
• IL-17 inhibitors (secukinumab, ixekizumab, brodalumab): Directly inhibit IL-17 5
• IL-12/23 inhibitors (ustekinumab): Target p40 subunit 5
• TNF inhibitors (adalimumab, etanercept, infliximab, certolizumab): Also effective for psoriatic arthritis 1, 6, 5

Traditional Systemic Agents:

• Methotrexate: Inhibits dihydrofolate reductase; requires monitoring of CBC, liver function tests, and serum creatinine 1, 2, 5
• Cyclosporine 3-5 mg/kg/day: Rapid onset (preferred for erythrodermic psoriasis); use in short 3-4 month courses; requires blood pressure and renal function monitoring 1, 3, 2
• Acitretin: Decreases keratinocyte hyperproliferation; contraindicated in women of childbearing potential due to teratogenicity 1, 3, 2

Oral Small Molecule:

• Apremilast: Phosphodiesterase 4 inhibitor for moderate-to-severe disease 5

Combination Strategies for Enhanced Efficacy

• Adding ultrahigh-potency topical corticosteroid to etanercept for 12 weeks enhances efficacy 3, 2
• Adding calcipotriene/betamethasone to adalimumab for 16 weeks accelerates clearance 3
• Adding topical calcipotriene to methotrexate improves outcomes 3
• All topical corticosteroids can be combined with any biologics 3

Special Populations and Conditions

Psoriatic Arthritis

• NSAIDs for mild joint symptoms 1
• DMARDs for moderate-to-severe joint involvement 1
• TNF inhibitors (adalimumab) for inadequate response to at least one DMARD—effective for both skin and joint symptoms 1, 6

Pediatric Psoriasis

• Juvenile Idiopathic Arthritis/Pediatric Uveitis (≥2 years): 3, 6

  • 10-15 kg: 10 mg every other week
  • 15-30 kg: 20 mg every other week
  • ≥30 kg: 40 mg every other week

• Crohn's Disease (≥6 years): 3, 6

  • 17-40 kg: Day 1: 80 mg, Day 15: 40 mg, then 20 mg every other week
  • ≥40 kg: Day 1: 160 mg, Day 15: 80 mg, then 40 mg every other week

• Hidradenitis Suppurativa (≥12 years): 6

  • 30-60 kg: Day 1: 80 mg, then 40 mg every other week starting Day 8
  • ≥60 kg: Day 1: 160 mg, Day 15: 80 mg, then 40 mg weekly or 80 mg every other week starting Day 29

Erythrodermic Psoriasis

• Oral cyclosporine 3-5 mg/kg/day is the logical choice for systemically ill patients due to rapid onset 1
• Mid-potency topical corticosteroids and emollients under occlusion may help restore barrier function 1
• Base therapy on short-term efficacy; transition to maintenance therapy after acute illness improves 1

Critical Pitfalls to Avoid

• Never use systemic corticosteroids in psoriasis—they cause disease flare during taper 1, 2
• Never combine salicylic acid with calcipotriene simultaneously—acidic pH inactivates calcipotriene 3, 2
• Limit continuous high-potency corticosteroid use to 4 weeks maximum to prevent skin atrophy, striae, telangiectasia, and HPA axis suppression 3, 2
• Do not use high-potency corticosteroids on face or flexures—use low-potency agents instead 3
• Apply vitamin D analogues after phototherapy, not before, to avoid inactivation 1
• Avoid drugs that may precipitate or worsen psoriasis: alcohol, beta-blockers, NSAIDs, lithium, chloroquine, and mepacrine 1

Safety Monitoring for Systemic Therapies

• Methotrexate: Regular CBC, liver function tests, serum creatinine 2
• Cyclosporine: Blood pressure, renal function, lipid profile 2
• Biologics: Screen for latent tuberculosis before initiating; monitor for serious infections during treatment 6
• Long-term high-potency corticosteroids (>12 weeks): Require careful physician supervision 3

Adjunctive Therapies

• Emollients (water-in-oil cream or lotion) can be used as corticosteroid-sparing agents when combined with betamethasone dipropionate 3
• Tacrolimus is first-line for intertriginous psoriasis due to efficacy without causing skin atrophy 3
• Oral curcumin supplementation may benefit as adjunctive therapy 1
• Mindfulness meditation and stress reduction can improve psoriasis severity in some patients 1