Management of Psoriasis
- Usually symmetrical erythematous plaques with a silvery surface scale
- Typically occurs on extensor surfaces and can be generalised or erythrodermic (erythroderma means around 90% of the body surface area is bright red)
- Koebner phenomenon
- Occurs at sites of trauma
- It is associated with nail changes and inflammatory arthritis
- Nail pitting, onycholysis, hyperkeratosis
See figure 1 for image of psoriasis.
Below is a stepped approach for newly diagnosed psoriasis. Patients with pre-existing psoriasis should be treated according to their symptoms.
Prescribe regular emollients four times a day. Examples include: Zerobase® and liquid and white soft paraffin. See GGC Adult Medicines Formulary for preferred choice. Important prescribing points:
- Avoid aqueous cream.
- In general, ointments are preferred for dry skin but are poorly tolerated.
- Creams and lotions are used on less dry skin and better tolerated.
- Calcipotriol 50 microgram per 1 gram ointment (or in combination with betamethasone 500 micrograms per 1 gram) once a day.
- Usual duration 4 weeks but longer if required.
- Prescribe appropriate quantities e.g. 120 gram.
- Large, thin plaques: coal tar preparations. See GGC Adult Medicines Formulary.
- Thin skin: calcitriol 3 microgram per 1 gram ointment or clobetasone butyrate 0.05% (Eumovate®) once a day.
- Dithranol remains the most effective topical treatment, especially for solitary plaques but can stain the skin, hair and fabrics. Discuss application with dermatology.
- For lesions with thick scale, it may be necessary to use descaling agents e.g. salicylic acid in yellow soft paraffin 5%. See GGC Adult Medicines Formulary.
- Consider tubular bandages for limbs.
Consider referral to local dermatology team
- In patients with severe psoriasis who are not responding to treatment.
- Suspected erythrodermic or pustular psoriasis.
- Where there is diagnostic uncertainty.
- Referral to GP surgery for skin monitoring post-discharge.
- Provide patient information leaflet from the British Association of Dermatologists website.
- Raise awareness of patient support groups.
- Assess patients for related comorbidities e.g. cardiovascular disease, psoriatic arthritis.
- Consider referral to Dermatology Specialist Nurse.
Guideline reviewed: August 2023
Page last updated: November 2023