Miscellaneous Preparations Used in the Treatment of Psoriasis

Preparation	Mode of action	Indications	Complications
Crude coal tar and coal tar solution	Unclear	Psoriasis	Messy to use
Derived from the distillation of organic matter	Tar has anti-proliferative effects on the epidermis	Used in combination with ultraviolet radiation with additive effects	Potent odour Scrotal squamous cell carcinoma
Dithranol	Unclear	Psoriasis	Local reactions and irritation of normal surrounding skin
Available in cream formulation or in Lassar's paste in concentrations from 0.1% to 3%	Dithranol has potent anti-proliferative effects	Short contact regimens used in outpatient settings	Skin staining
Vitamin D3 analogues: Calcipotriol (Dovonex^®), and tacalcitol (Silkis^®) Combination of calcipotriol and betamethasone (Dovobet^® gel and Enstilar^® spray)	Regulate cell growth, differentiation, and immune function	Psoriasis	Hypercalcaemia Irritation Prolonged use of betamethasone and calcipotriol may precipitate the formation of pustules on withdrawal