Determination of disulfiram and its metabolites in human blood

This work was initiated by the lack of a sensitive method for the determination of disulfiram and its metabolites in blood of patients treated with this drug. A method is described which allows the separate determination of carbon disulfide, free diethyldithiocarbamate and disulfides derived from disulfiram with adequate precision in 10 ml patient blood. It is based on a spectrophotometric determination of a yellow compound formed by trapping carbon disulfide produced from diethyldithiocarbamate and disulfiram in an ethanolic solution of diethylamine and copper(II)-acetate. Good quantitation of disulfiram and diethyldithiocarbamate in blood was achieved by trapping carbon disulfide produced when formic acid and cystein were added to the samples. During daily administration of 200 mg disulfiram to humans, concentrations of zero to 0.6 mug carbon disulfide and 0.2 to 1.0 mug diethyldithiocarbamate per ml blood were found using this method.