THE PREVENTION OF NICKEL CONTACT-DERMATITIS - A REVIEW OF THE USE OF BINDING-AGENTS AND BARRIER CREAMS

Chelating agents and other substances can be used to bind nickel or re duce its penetration through the skin, and hence to reduce the symptom s in subjects with nickel sensitivity. Topical usage is mostly describ ed but, in some studies, chelating agents have been given systemically . The most effective ligand for nickel so far described is 5-chloro-7- iodoquinolin-8-ol. Although normally regarded as safe, its usage in so me situations may be limited by concerns about its toxicity. Other lig ands with demonstrable effect include ethylenediaminetetraacetic acid in various forms, diphenylglyoxime and dimethylglyoxime. Cation exchan ge resins can effectively bind nickel and work both in vitro and in vi vo. Propylene glycol, petrolatum and lanolin reduce the absorption of nickel through the skin. Corticosteroids and cyclosporin work in nicke l dermatitis by suppressing the immunological reaction rather than thr ough an effect on nickel. Studies of the oral administration of ligand s such as tetraethylthiuram disulphide have given conflicting results but the use of these agents is limited by hepatotoxicity in any case. Some compounds offer potential for use in the prophylaxis of nickel de rmatitis. Further work is required to develop the existing agents and to look at the use of novel combinations, such as that of a cation exc hanger with a ligand.