The possible chelating effect of sodium diethyldithiocarbamate (DDC) in nickel allergic patients. Patch test procedures with nickel on DDC pretreated skin.
Encouraged by some reports about the chelating effect of p.o. given sodium diethyldithiocarbamate (DDC) in nickel allergic patients, some experiments were performed to determinate the blocking effect of locally applied DDC on positive patch test reactions with nickel. Two groups of nickel allergic patients were patch tested with different concentrations of nickel sulphate on with DDC treated skin. Control patch tests were done on areas which were pretreated with the creambase only. In one group 10% DDC in the cream was applied under 24 h occlusion; in this group also a nickel coin was tested. In the second group of patients the DDC cream was rubbed four times during 24 h without occlusion. In both groups there were no statistical differences regarding the reactions on skin pretreated with DDC and with the cream base. From this investigation it may be concluded that there is no indication that a DDC-containing barriercream will be of great help in patients with occupational dermatitis, which is especially due to nickel sensitization.