What are the management options for a patient with typical chronic plaque psoriasis?

Management of Chronic Plaque Psoriasis

Initial Treatment Algorithm

Start with combination calcipotriol/betamethasone dipropionate (vitamin D analogue + potent corticosteroid) applied once daily for 4 weeks, which achieves 2.2-point improvement on a 6-point scale and provides superior efficacy to either agent alone. 1

Mild to Moderate Disease (Body Surface Area <5%)

Topical Therapy Approach:

• First-line: Apply calcipotriol/betamethasone dipropionate combination product once daily to affected areas for 4 weeks 1

  • This combination achieves maximal improvement within 4 weeks in the majority of patients 2
  • Provides 58-92% clearance rates 3
  • Better tolerated than vitamin D alone, with similar tolerability to corticosteroids alone 1, 2

• Alternative first-line regimens if combination unavailable:

  • High-potency corticosteroids (Class 2-3) twice daily for 2-4 weeks maximum 1, 3
  • Vitamin D analogues (calcipotriene) twice daily for up to 52 weeks 1
  • Morning high-potency corticosteroid + evening vitamin D analogue 1

• Maintenance therapy after initial clearance:

  • Vitamin D analogues twice daily on weekdays + high-potency corticosteroids twice daily on weekends 1
  • This regimen reduces corticosteroid exposure while maintaining control 1

Critical Safety Monitoring for Topical Therapy:

• Conduct clinical review every 4 weeks during active treatment 4
• No unsupervised repeat prescriptions for high-potency agents 1, 3
• Limit moderate-potency corticosteroid use to maximum 100g per month 1, 3
• Implement periods each year when alternative treatments are employed to prevent tachyphylaxis 3
• Use low-potency corticosteroids on face, intertriginous areas, and forearms to minimize atrophy risk 1, 3

Special Site Considerations:

• Scalp psoriasis: Calcipotriene foam or calcipotriene/betamethasone dipropionate gel for 4-12 weeks 1
• Facial psoriasis: Tacalcitol ointment or calcipotriene combined with hydrocortisone for 8 weeks 1
• Nail psoriasis: Calcipotriene combined with betamethasone dipropionate, though efficacy limited by poor penetration 1

Moderate to Severe Disease (Body Surface Area >5% or Failed Topical Therapy)

Escalate to systemic therapy when: 1, 3, 4

• Body surface area involvement exceeds 5%
• Inadequate response to optimized topical therapy after 8 weeks
• Repeated hospital admissions required for topical treatment
• Extensive chronic plaque psoriasis in elderly or infirm patients
• Generalized pustular or erythrodermic psoriasis
• Severe psoriatic arthropathy

Systemic Treatment Selection Algorithm:

First-line systemic: Phototherapy (PUVA or narrowband UVB) 1, 3

• Start PUVA at 70% of minimum phototoxic dose 1, 3
• Increase successive doses by 40% if no erythema develops 1, 3
• Response time: 4 weeks 1
• Least toxic systemic option 3

Second-line systemic (if phototherapy fails or contraindicated): Conventional systemic agents 1

• Methotrexate:

  • Response time: 2 weeks 1
  • Initial dose: maximum 0.2 mg/kg body weight 1
  • Especially useful for pustular psoriasis, erythroderma, psoriatic arthritis, extensive disease in elderly 1
  • Absolute contraindications: pregnancy, breastfeeding, wish to father children, significant hepatic damage, anemia, leucopenia, thrombocytopenia 1
  • Monitoring: Weekly full blood count, liver function tests, serum creatinine initially, then every 1-2 months when stable 1
  • Avoid drugs that interact with methotrexate 1

• Cyclosporine:

  • Starting dose: 2.5 mg/kg/day divided twice daily 5
  • Increase by 0.5 mg/kg/day every 2 weeks if needed, maximum 4 mg/kg/day 5
  • Response time: 3 weeks 1
  • Absolute contraindications: abnormal renal function, uncontrolled hypertension, previous or concomitant malignancy 1
  • Monitoring: Blood pressure and serum creatinine at each visit 1, 5
  • Decrease dose by 25-50% if creatinine rises ≥25% above baseline 5
  • Maximum treatment duration: 1 year - discontinue and alternate with other treatments due to nephrotoxicity risk 5

• Acitretin (Retinoids):

  • Response time: 6 weeks 1
  • Especially effective for pustular psoriasis 1
  • Absolute contraindication: pregnancy or wish to conceive within 2 years of stopping treatment 1
  • Monitoring: Liver function tests and fasting serum lipids 1

Third-line systemic: Biologic therapy 3

• Consider when conventional systemic agents fail, are contraindicated, or not tolerated
• Achieve treatment goals in 68.2-79.3% of patients by week 16 3
• Screen for: active or latent tuberculosis, hepatitis B, fungal infections before initiating 3, 6
• Can be combined with methotrexate or topical high-potency corticosteroids 3

Special Considerations for Pustular Psoriasis

Infliximab is first-line biologic therapy for generalized pustular psoriasis - demonstrates rapid and often complete disease clearance 3

• Standard dosing: 5 mg/kg infused at weeks 0,2, and 6, then every 8 weeks 3

Never use systemic corticosteroids - risk of disease exacerbation upon discontinuation, can precipitate erythrodermic or generalized pustular psoriasis 3, 7

Medications That Worsen Psoriasis (Avoid or Use Cautiously)

• Lithium: can cause severe, life-threatening deterioration 1, 7
• Antimalarials (chloroquine, mepacrine): may cause severe deterioration 1, 7
• Beta-blockers: can exacerbate disease 1, 7
• NSAIDs: may worsen existing psoriasis 1, 7
• Alcohol: can precipitate or worsen disease 1, 7

Common Pitfalls to Avoid

Perceived "tachyphylaxis" to topical corticosteroids is usually poor adherence, not true receptor down-regulation - address compliance issues before switching therapies 3

Avoid combining salicylic acid with calcipotriene - the acidic pH inactivates calcipotriene and reduces effectiveness 1

Do not use PUVA, UVB, or other immunosuppressive agents concurrently with cyclosporine - excessive immunosuppression increases malignancy risk 5

Trial alternative topical agents before escalating to systemic therapy - patients who fail one topical agent may respond to another 1, 3

For women of childbearing potential on methotrexate: contraception required during treatment and for at least one menstrual cycle after stopping 1

For women on acitretin: contraception required during treatment and for 2 years after stopping due to prolonged teratogenic potential 1