PHARMACOLOGY OF 2,3-DIMERCAPTOSUCCINIC ACID AND ITS POTENTIAL USE IN ARSENIC POISONING

Abstract

AS2O3-poisoned rats were treated with either 2,3-dimercaptosuccinic acid (DMS) or dimercaptopropanol (BAL) at doses of 30 mg/kg per day. A control group received no treatment. The total quantity of As2O3 excreted was not significantly different in response to 4 days of treatment with either DMS or BAL. There was no difference between the 2 drug treatment groups in the residual As2O3 content of brain, liver, kidney and spleen after treatment. Both drugs reduced the arsenic content of each tissue to approximately 40% of that of untreated controls. Previous studies have shown that DMS is orally effective for the treatment of Pb poisoning. The LD50 of DMS was in excess of 3 g/kg in rats and mice, approximately 30 times the LD50 of BAL. No gross, histopathological or biochemical evidence of toxicity was observed in mice, rats or dogs which received DMS 5 days/wk for 6 mo. DMS did not affect the excretion of Zn, Fe, Ca or Mg. Urinary Cu excretion was significantly elevated in response to 30 mg/kg of DMS, suggesting that the drug might also be useful for the treatment of Wilson''s disease.