Topical immunotherapy in dermatology.

Topical immunotherapy of skin diseases has been used since the 1970s to treat conditions thought to result from an altered immunological state, mainly extensive alopecia areata and resistant viral warts. Despite its effectiveness, only a handful of dermatology departments in the UK currently provide such treatment. Any of three universal contact sensitisers may be used for topical immunotherapy; but diphencyprone (DCP) has advantages over dinitrochlorobenzene (DNCB) and squaric acid dibutyl ester (SADBE). Sensitisation of medical, nursing and pharmacy staff may be avoided by careful handling of the solutions. Local blistering and eczematous eruptions are the most common risks in patients undergoing treatment; vitiligo and erythema multiforme-like reactions are rare complications. Topical immunotherapy using DCP with close supervision is a useful option for severe alopecia areata and resistant viral warts.