The metabolism of 14C-disulfiram by the rat

After administration of 14C-disulfiram to rats by stomach tube, we found that 87% of the radioactivity was excreted in urine and 7% in feces. Greater than 80% of the radioactivity was excreted by 48 hr. Small but measurable radioactivity was excreted in urine up to 144 hr after administration. Total recovery of radioactivity at 144 hr was 95% of the ingested dose with less than 1% in organs, blood, and carcass; the remainder was in urine and feces. Studies on specific radioactivity showed that diethylamine, a major urinary metabolite of disulfiram, is excreted in the urine undiluted with endogenous diethylamine. Pretreatment of rats with unlabeled disulfiram leads to a more rapid catabolism of the radioactive drug and more rapid excretion of radioactivity in the urine. Further, pretreatment appears to induce formation of a glucuronide conjugate of a disulfiram metabolite.