Sensitization to sodium hypochlorite causing hand dermatitis

2 patients are reported with chronic hand dermatitis related to sensitization to sodium hypochlorite, as the active component in a bleaching product. To avoid irritant reactions in patch testing, a sodium hypochlorite concentration of 1.0% appeared to be useful. It is concluded that with regard to the frequent use of bleaching agents, allergy to sodium hypochlorite must be considered in certain cases of unidentified chronic allergic hand dermatitis.