Psoriasis Treatment Guidelines

Disease Classification and Treatment Selection

The American Academy of Dermatology recommends that psoriasis severity be categorized as mild (typically <5% body surface area [BSA]) or moderate-to-severe (≥5% BSA or involvement of vulnerable areas) 1
Patients with symptomatic psoriasis (pain, bleeding, itching) should be considered for systemic or phototherapy even if BSA involvement is limited, according to the American Academy of Dermatology 1
Quality of life impact should be considered when selecting therapy, as psychological distress can be significant regardless of physical extent, as noted by the American Academy of Dermatology 1

For mild psoriasis, the American Academy of Dermatology recommends first-line treatment with topical therapies such as topical corticosteroids, classified into 7 potency categories, with ultra-high potency (class 1) for thick plaques and lower potency for sensitive areas 2
Vitamin D analogs (calcipotriene, calcitriol) are recommended for mild psoriasis, with a maximum of 100g per week to avoid hypercalcemia, according to the Journal of the American Academy of Dermatology 3
Combination products (calcipotriene/betamethasone dipropionate) simplify the regimen and improve compliance for mild psoriasis, as noted by the Journal of the American Academy of Dermatology 3
For moderate-to-severe psoriasis, phototherapy is recommended as a first-line treatment, including narrowband UVB and PUVA (psoralen plus UVA), according to the American Academy of Dermatology 1
The 308-nm excimer laser is recommended for localized resistant areas of moderate-to-severe psoriasis, as noted by the Journal of the American Academy of Dermatology 3

For scalp psoriasis, treatment options include calcipotriene foam or calcipotriene plus betamethasone dipropionate gel for 4-12 weeks, according to the American Academy of Dermatology 1
Excimer laser therapy is recommended for resistant cases of scalp psoriasis, as noted by the Journal of the American Academy of Dermatology 3
Low-potency corticosteroids are recommended for facial and intertriginous psoriasis to avoid skin atrophy, according to the American Academy of Dermatology 1
Topical calcitriol is less irritating than other vitamin D analogs and better tolerated on sensitive skin areas, such as the face and intertriginous areas, as noted by the Journal of the American Academy of Dermatology 3

Regular clinical review is required for patients using topical corticosteroids, according to the BMJ 4
No unsupervised repeat prescriptions should be made for topical corticosteroids, as noted by the BMJ 4
No more than 100g of a moderately potent preparation should be applied each month, according to the BMJ 4

Systemic corticosteroids should be avoided in psoriasis as they can cause disease flare during taper, according to the American Academy of Dermatology 1
Long-term use of potent topical corticosteroids can cause skin atrophy, striae, and telangiectasia, as noted by the American Academy of Dermatology 1
Vitamin D analogs should be applied after phototherapy to avoid inactivation, according to the American Academy of Dermatology 1
Drugs that may worsen psoriasis include alcohol, beta-blockers, NSAIDs, lithium, chloroquine, and mepacrine, as noted by the BMJ 4

Combination therapy with topical corticosteroids plus vitamin D analogs enhances efficacy and reduces irritation, according to the American Academy of Dermatology 1
Rotational therapy (switching between treatment modalities every 1-2 years) may minimize cumulative toxicity of individual treatments, as noted by the American Academy of Dermatology 1

The National Psoriasis Foundation's consensus defines moderate-to-severe disease as ≥5% body surface area (BSA) involvement, and treatment intensity decisions should also consider quality of life impact and symptom severity (pain, bleeding, itching) 5, 6

The American Academy of Dermatology recommends starting with high-potency topical corticosteroids, such as clobetasol propionate 0.05% cream or ointment, applied twice daily to affected areas, which achieves 58-92% efficacy in psoriasis trials 7, 8, 9
Combination therapy with topical vitamin D analogs (calcipotriene) enhances efficacy and reduces irritation compared to monotherapy 7, 8, 9

For moderate disease extent, the American Academy of Dermatology recommends adding narrowband UVB phototherapy as first-line treatment, and applying vitamin D analogs after phototherapy sessions to avoid inactivation 7, 8, 9

If inadequate response after 4-8 weeks of topical therapy plus phototherapy, consider systemic therapy including methotrexate, cyclosporine, acitretin, or biologic agents, as recommended by the National Comprehensive Cancer Network 7, 8, 9
Apremilast or acitretin can be considered for moderate disease if phototherapy is unavailable or contraindicated 7, 8, 9