The therapeutic use of topical contact sensitizers in benign dermatoses

Topical therapy using contact sensitizers has been practised since the 1960 s to treat conditions associated with an altered immunological state. Dinit rochlorobenzene, squaric acid dibutyl ester and diphencyprone are most comm only employed in the therapy of alopecia areata and viral warts. Few dermat ology departments in the U.K. provide such treatment. This systematic revie w discusses the various contact sensitizers used for topical immunotherapy, the methodology of treatment, factors influencing efficacy and likely adve rse effects.