2,3-Dimercaptosuccinic acid as an antidote for lead intoxication

Abstract

2,3-Dimercaptosuccinic acid (DMSA) is an orally effective drug more specific and with a wider therapeutic index than currently available drugs for Pb intoxication. Men (18) with elevated blood lead (BPb) concentrations received either 30, 20 or 10 mg/kg DMSA for 5 days in 3 divided daily doses. The mean BPb level decreased 72.5%, 58.3% and 35.5% of the pretreatment values, with a simultaneous elevation in urinary Pb excretion. Clinical symptoms and biochemical indices of Pb toxicity also improved. Red blood cell d-aminolevulinic acid dehydratase activity increased, while urinary excretion of d-aminolevulinic acid and coproporphyrin fell. DMSA was well tolerated: the only observed adverse drug reaction was a mild, transient elevation of serum SGPT [serum glutamic pyruvic transaminase] levels in 2 subjects. DMSA appears promising and may greatly simplify the treatment of Pb intoxication.