Current Treatment Options for Psoriasis
Disease Severity Classification and Treatment Selection
For mild psoriasis (typically <5% body surface area), start with combination topical therapy using calcipotriene/betamethasone dipropionate once daily for 4-8 weeks, which achieves clear or almost clear status in 48-74% of patients 1, 2. However, patients with symptomatic psoriasis (pain, bleeding, itching) require systemic or phototherapy regardless of body surface area involvement 1, 2.
Defining Treatment Thresholds
- Mild psoriasis candidates for topical therapy alone must be generally asymptomatic and have <5% body surface area involvement 1
- Moderate-to-severe psoriasis (≥5% BSA or involvement of vulnerable areas like face, genitals, hands, feet, or scalp) requires phototherapy or systemic agents as first-line treatment 2, 3
- Quality of life impact should drive treatment intensity—psychological distress warrants escalation even with limited physical extent 3
First-Line Topical Therapy for Mild Psoriasis
Primary Regimen
Apply calcipotriene/betamethasone dipropionate combination product once daily for 4-8 weeks 1, 2. This represents the most effective topical approach based on current evidence.
- For trunk and extremities: use high-potency corticosteroids (clobetasol propionate 0.05% or halobetasol propionate 0.05%) 4, 2
- Maximum vitamin D analogue use: 100g per week to avoid hypercalcemia 1, 2
- Efficacy of vitamin D analogues appears at 8 weeks but not at 4 weeks—counsel patients accordingly 4
Site-Specific Modifications
- Facial/intertriginous areas: Use low-potency corticosteroids or calcitriol ointment to prevent skin atrophy 1, 2. Alternatively, calcipotriene combined with hydrocortisone for 8 weeks is effective 4
- Scalp psoriasis: Use calcipotriene foam or calcipotriene plus betamethasone dipropionate gel for 4-12 weeks 4, 1, 2. After 8 weeks, 40.9% achieve clear or almost clear status versus 24.2% with vehicle 4
- Inverse psoriasis: Off-label tacrolimus or pimecrolimus for 4-8 weeks is recommended 4. Long-term use can be considered despite boxed warning for malignancy (no evidence shows increased risk with topical use) 4
- Nail psoriasis: Calcipotriene combined with betamethasone dipropionate reduces nail thickness and hyperkeratosis, though efficacy is limited due to poor nail matrix penetration 1
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) 1. This minimizes corticosteroid exposure while maintaining efficacy.
Critical Pitfalls to Avoid with Topical Therapy
- Never combine salicylic acid with calcipotriene simultaneously—the acidic pH inactivates calcipotriene and eliminates its effectiveness 1, 2
- Avoid systemic corticosteroids in psoriasis—they cause disease flare during taper 2, 3
- Limit continuous high-potency corticosteroid use to prevent skin atrophy, striae, telangiectasia, and HPA axis suppression 1, 2
- Do not use high-potency corticosteroids on face or flexures—use low-potency agents or tacrolimus instead 1
- Apply vitamin D analogues after phototherapy to avoid inactivation 3
Phototherapy for Moderate-to-Severe Psoriasis
For patients with ≥5% BSA or inadequate response to topicals, initiate narrowband UVB phototherapy as first-line systemic treatment 2, 5. This represents the standard escalation before traditional systemic agents or biologics.
- Phototherapy options include narrowband UVB, oral PUVA, and bath PUVA with or without acitretin 4
- An initial trial of phototherapy should be attempted unless inappropriate or if psoriasis involves areas precluding phototherapy (scalp, groin, axilla) 4
- Avoid aggressive immunosuppression following extensive PUVA therapy due to increased melanoma and non-melanoma skin cancer risk 4
Traditional Systemic Agents for Moderate-to-Severe Psoriasis
Methotrexate
- Inhibits dihydrofolate reductase and increases endogenous adenosine with anti-inflammatory effects 2
- Requires regular monitoring: complete blood count, liver function tests, and serum creatinine 2
- Effective for both skin and joint manifestations in psoriatic arthritis 4, 3
Cyclosporine
For rapid onset of action, use cyclosporine 3-5 mg/kg/day in short 3-4 month "interventional" courses 1. This is particularly effective for erythrodermic psoriasis requiring rapid response 1.
- Requires monitoring of blood pressure, renal function, and lipid profile 2
- Should be limited to less than 12 consecutive months due to cumulative toxicity concerns 4
- Base therapy for erythrodermic psoriasis on short-term efficacy, then transition to maintenance therapy after acute illness improves 1
Acitretin
- Decreases keratinocyte hyperproliferation and restores normal epidermal differentiation 1, 2
- Cannot be used in women of childbearing potential due to teratogenicity 1
- Has slower onset of action compared to cyclosporine 1
Biologic Therapies for Moderate-to-Severe Psoriasis
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.
TNF-α Inhibitors
- Etanercept, adalimumab, certolizumab, and infliximab 5
- Equally effective for peripheral arthritis and inhibition of radiographic progression in psoriatic arthritis 4
- Adalimumab dosing: 40 mg every other week subcutaneously 6. Some patients not receiving methotrexate may benefit from increasing to 40 mg every week or 80 mg every other week 6
IL-17 Inhibitors
- Secukinumab, ixekizumab, bimekizumab, and brodalumab 5
- Approved for both plaque psoriasis and psoriatic arthritis 5
IL-23 Inhibitors (p19 subunit)
- Guselkumab, tildrakizumab, risankizumab, and mirikizumab 5
- Represent newer generation biologics with favorable efficacy profiles
IL-12/23 Inhibitor (p40 subunit)
Biologic Safety Considerations
- Boxed warning for TNF inhibitors: Increased risk of serious infections (tuberculosis, bacterial sepsis, invasive fungal infections) and malignancies including lymphoma 6
- Perform test for latent TB before starting; if positive, treat TB prior to initiating biologic 6
- Monitor all patients for active TB during treatment, even if initial latent TB test is negative 6
- Discontinue if patient develops serious infection or sepsis 6
Combination Strategies to Enhance Efficacy
Adding ultra-high potency topical corticosteroid to biologic therapy for 12 weeks accelerates clearance and improves outcomes 2. In one study, 81.0% of patients with moderate disease achieved clear or almost clear status when clobetasol propionate spray 0.05% was added to stable biologic therapy 7.
- Combining tazarotene with medium- or high-potency corticosteroids for 8-16 weeks increases efficacy while reducing local adverse events and prolonging remission 1
- Combination treatments with vitamin D analogues and potent topical corticosteroids for 3-52 weeks are more effective than either agent alone 4
Treatment Algorithm for Psoriatic Arthritis
Peripheral Arthritis
- Mild disease: NSAIDs for control of joint symptoms (not skin symptoms) 4. Intra-articular glucocorticoid injections may be given judiciously, avoiding injection through psoriatic plaques 4
- Moderate or severe disease: DMARDs (sulfasalazine, leflunomide, methotrexate, or cyclosporine) 4
- Failure of at least one DMARD: TNF inhibitors (etanercept, infliximab, or adalimumab) 4. Patients with poor prognosis could be considered for TNF inhibitors even without prior DMARD failure 4
Axial Disease
- Mild to moderate: NSAIDs, physiotherapy, education, analgesia, and sacroiliac joint injection 4
- Moderate to severe: TNF inhibitors (infliximab, etanercept, or adalimumab) 4. Traditional oral DMARDs like methotrexate, leflunomide, and sulfasalazine have not been shown effective for axial manifestations 4
Enthesitis and Dactylitis
- Mild: NSAIDs, physical therapy, corticosteroids 4
- Moderate: DMARDs 4
- Severe or resistant: TNF inhibitors (infliximab or etanercept) 4
Drugs That Worsen Psoriasis
Avoid or use with extreme caution: Lithium, chloroquine, and mepacrine may cause severe, even life-threatening deterioration 4, 3. Beta-blockers, NSAIDs, and alcohol may also precipitate or worsen psoriasis in some patients 4, 3.