Dermatology/Topical psoriasis agent

Topical psoriasis agents

also: calcipotriol · vitamin D analogue · coal tar · dithranol · Dovobet

Overview

Topical treatment of plaque psoriasis. First-line is a potent corticosteroid PLUS a vitamin D analogue.

Mechanism

Vitamin D analogues (calcipotriol/calcitriol) bind the vitamin D receptor → normalise keratinocyte proliferation/differentiation + immunomodulation. Coal tar is antiproliferative and antipruritic; dithranol is antiproliferative (inhibits DNA synthesis).

Indications

Chronic plaque psoriasis
Scalp psoriasis (gel/foam)

The agents

Calcipotriol / calcitriolvitamin D analogue

Combined with betamethasone = Dovobet/Enstilar.

Coal tarantiproliferative

Scalp/plaques; smell + staining.

Dithranolantiproliferative

short-contact

Stains skin/clothes/bath; specialist/day-centre.

Adverse effects

Local irritation / burningcommon

Hypercalcaemia (calcipotriol, if excessive)serious

Respect the weekly maximum.

Coal tar/dithranol: staining, photosensitivity, folliculitiscommon

Cautions & contraindications

Calcipotriol in disorders of calcium metabolismall

Erythrodermic / unstable / pustular psoriasis (dithranol, tar)all

Interactions

Monitoring & kinetics

Calcium if high-dose calcipotriol; treatment area

Topical. First-line regimen: potent steroid (am) + vitamin D analogue (pm), or a combined product OD.

Source: NICE CG153 — Psoriasis · BNF — Psoriasis (topical)