Dithiocarbamate therapy for nickel dermatitis.

Increased internal exposure to nickel can cause an exacerbation of nickel contact dermatitis. Nickel ions are chelated by diethyldithiocarbamate (DDC) and thereby inactivated. An oral dose of about 1 g DDC/day was given to a patient. The nickel excretion in the urine increased about tenfold; the nickel elimination in scalp hair did not increase. The slightly negative nickel balance did not exhaust the nickel content of the organs appreciably with a dose of 1.2 g DDC/day for 2 months. At the end of this experiment patch tests with nickel sulphate were still positive though less local therapy was needed, and the cross correlation between the activity of the eczema and the nickel concentration in the urine had lost its former periodicity. It is therefore not yet possible to conclude whether or not DDC may be really of help in the very nickel hypersensitive patient by reducing the exposure to nickel originating in food and other environmental sources.