What are the treatment options for a patient with psoriasis?

Psoriasis Treatment

For mild psoriasis (<5% body surface area), initiate treatment with high-potency topical corticosteroids combined with calcipotriene (vitamin D analog), which achieves 58-92% clearance rates and represents the most effective first-line approach. 1, 2, 3

Treatment Algorithm Based on Disease Severity

Mild Psoriasis (<5% BSA)

First-Line Topical Therapy:

• Apply clobetasol propionate 0.05% or betamethasone dipropionate 0.05% twice daily to body plaques for a maximum of 2-4 weeks 1, 2
• Combine with calcipotriene for synergistic effect—this combination is superior to either agent alone and reduces irritation 1, 4
• Use low-potency corticosteroids or topical calcineurin inhibitors on sensitive areas (face, genitals, intertriginous areas) to minimize atrophy risk 3
• Limit moderate-potency corticosteroid use to maximum 100g per month with regular clinical review and no unsupervised repeat prescriptions 5, 3

Alternative Topical Options if First-Line Fails:

• Coal tar: Start with 0.5-1.0% crude coal tar in petroleum jelly, increasing concentration every few days to maximum 10% 5, 3
• Dithranol (anthralin): Start at 0.1-0.25% concentration, increase in doubling concentrations as tolerated; use "short contact mode" (15-45 minutes every 24 hours) to minimize irritancy and staining 5, 3
• Tazarotene: Add to moderate-to-high potency corticosteroids for body plaques to reduce irritation and enhance efficacy 3

Moderate-to-Severe Psoriasis (≥5% BSA or Quality of Life Impairment)

Escalation Criteria:

• Body surface area involvement exceeds 5% 1, 2, 3
• Inadequate response to optimized topical therapy after 8 weeks 3
• Psoriasis in vulnerable areas (face, genitals, hands, feet, scalp) unresponsive to topical therapy 5
• Concurrent psoriatic arthritis requiring systemic therapy 5
• Major quality-of-life issues warranting systemic therapy from onset 5

First-Line Systemic Treatment:

Phototherapy (PUVA) is the least toxic systemic agent and should be considered first-line 1, 2, 3

• Start at 70% of minimum phototoxic dose 1, 3
• Increase successive doses by 40% if no erythema develops 1, 3
• Narrowband UVB is also first-line and preferred in pregnancy (lacks systemic toxicities) 1, 2
• 308-nm excimer laser allows selective targeting of localized resistant areas (scalp, skin folds) 1

Traditional Systemic Agents:

Methotrexate:

• Response time: 2 weeks 1, 3
• Especially useful in acute generalized pustular psoriasis, psoriatic erythroderma, psoriatic arthritis, and extensive chronic plaque psoriasis 2, 3
• Absolute contraindications: pregnancy, breastfeeding, wish to father children, significant hepatic damage, anemia, leucopenia, thrombocytopenia 3

Cyclosporine:

• Dosing: 3-5 mg/kg/day divided twice daily 1, 6
• Provides most rapid onset of action (3 weeks) for moderate-to-severe psoriasis requiring rapid response 1
• First-line for erythrodermic psoriasis with dramatic improvement during 2-3 weeks 2, 3
• Use in short 3-4 month "interventional" courses 1
• Initial dose for psoriasis: 2.5 mg/kg/day; if no improvement after 4 weeks, increase by 0.5 mg/kg/day at 2-week intervals to maximum 4 mg/kg/day 6
• Critical monitoring: Reduce dose by 25-50% if serum creatinine increases ≥25% above pretreatment level; discontinue if dose reduction ineffective 6
• Nephrotoxicity risk: 21-30% develop cyclosporine nephropathy with prolonged use (>15 months) or doses >5 mg/kg/day 6
• Malignancy risk: 2.2% developed tumors in clinical trials; do not use concurrently with PUVA, UVB, or other immunosuppressive agents 6

Acitretin:

• Response time: 6 weeks 3
• Alternative for erythrodermic psoriasis and pustular psoriasis 2, 3
• Absolutely contraindicated in pregnancy 2

Biologic Therapy for Severe Disease

Indications:

• Moderate-to-severe psoriasis inadequately controlled with traditional systemic agents 1, 2
• Psoriatic arthritis requiring systemic therapy 1
• Generalized pustular psoriasis 1, 2, 3

First-Line Biologic for Generalized Pustular Psoriasis:

• Infliximab demonstrates rapid and often complete disease clearance and should be considered first-line biologic therapy 1, 2, 3
• Dosing: 5 mg/kg infused at weeks 0,2, and 6, then every 8 weeks thereafter 1

Other Biologics:

• Adalimumab, ustekinumab, etanercept achieve treatment goals in 68.2-79.3% of patients by week 16 2, 3
• Adalimumab is effective for both skin and joint symptoms in psoriatic arthritis 1
• Can be combined with methotrexate or topical high-potency corticosteroids for enhanced efficacy 2, 3

Important Safety Considerations:

• Screen for active or latent tuberculosis, hepatitis B, and fungal infections before initiating biologics 3
• Increased risk of serious infections and cancer 3

Combination Strategies to Enhance Efficacy

Adding topical therapy to systemic agents accelerates clearance and improves outcomes: 1

• Ultrahigh-potency topical corticosteroid added to standard dose etanercept for 12 weeks 1
• Calcipotriene/betamethasone added to standard dose adalimumab for 16 weeks accelerates clearance 1
• Topical calcipotriene added to standard dose methotrexate improves outcomes 1

Special Considerations for Specific Psoriasis Types

Guttate Psoriasis

• Often self-limiting with no further attacks 5
• Use low concentrations of tar and dithranol (less tolerant of topical treatment) 5
• Ultraviolet B radiation may be especially helpful 5
• Investigate for streptococcal infection; treat with phenoxymethylpenicillin or erythromycin if present 5
• Consider tonsillectomy for repeated attacks after documented episodes of tonsillitis 5

Erythrodermic Psoriasis

• Initial management: Apply wet dressings with mid-potency topical steroids, maintain fluid balance, rule out sepsis with blood cultures 2
• First-line systemic: Oral cyclosporine 3-5 mg/kg/day due to rapid and impressive onset of action 1, 2
• Alternative options: acitretin, biologic agents, methotrexate 2

Pustular Psoriasis

• Methotrexate is especially useful in acute generalized pustular psoriasis 2, 3
• Infliximab for rapid and complete clearance 1, 2, 3
• Avoid systemic corticosteroids due to risk of disease exacerbation upon discontinuation 3

Critical Medications to ABSOLUTELY AVOID

Systemic Corticosteroids:

• NEVER prescribe systemic corticosteroids for psoriasis—they precipitate erythrodermic psoriasis, generalized pustular psoriasis, or very unstable disease upon discontinuation 1, 2, 3
• Can cause severe, potentially fatal deterioration when discontinued 1

Other Medications That Worsen Psoriasis:

• Lithium, chloroquine, and mepacrine are associated with severe, potentially fatal psoriasis deterioration 1, 2, 3
• Beta-blockers, NSAIDs, and alcohol may worsen psoriasis 1

Pregnancy Considerations

• NB-UVB phototherapy is first-line for pregnant women with moderate-to-severe psoriasis (lacks systemic toxicities and immunosuppressive properties) 2
• All commonly used systemic agents (methotrexate, acitretin, cyclosporine) are absolutely contraindicated in pregnancy 2, 3

Common Pitfalls and How to Avoid Them

Perceived "Tachyphylaxis" to Topical Corticosteroids:

• Often due to poor patient adherence rather than true receptor down-regulation 3
• Address compliance issues before switching therapies 3
• Implement periods each year when alternative treatments are employed to prevent true tachyphylaxis 3

Failure to Try Alternative Topical Agents:

• Patients who fail to respond to one topical agent may respond to another 5, 3
• Trial alternative topical agents before escalating to systemic therapy 5, 3

Inadequate Monitoring with Cyclosporine:

• Monitor serum creatinine regularly—dose reduction or discontinuation required if creatinine increases ≥25% above baseline 6
• Limit continuous treatment to <1 year; alternation with other forms of treatment should be considered 6
• Biopsy skin lesions not typical of psoriasis before starting treatment (malignant lesions may be hidden by psoriatic plaques) 6

Concurrent Use of Immunosuppressive Therapies:

• Do not combine cyclosporine with PUVA, UVB, other radiation therapy, or other immunosuppressive agents due to excessive immunosuppression and subsequent risk of malignancies 6