We compared the pharmacokinetics of meso-2,3-dimercaptosuccinic
acid (
DMSA) in three children with
lead poisoning, three adults with
lead poisoning, and five healthy adult volunteers. All subjects received
DMSA orally. Maximum blood concentration and time to maximum blood concentration of total
DMSA concentration were not statistically different among the groups. Unaltered
DMSA was detected in the blood of all poisoned patients but in only one of five healthy volunteers. Elimination half-life of total
DMSA (parent
drug plus oxidized metabolites) was longer in children with
lead poisoning (3.0 +/- 0.2 hours) than in adults with
lead poisoning (1.9 +/- 0.4 hours) and healthy adults (2.0 +/- 0.2 hours). Renal clearance of total
DMSA was greater in healthy adults (77.0 +/- 13.2 ml/min per square meter) than in either adults (24.7 +/- 3.3 ml/min per square meter) or children with
lead poisoning (16.6 ml/min per square meter); renal clearance of the metabolites of
DMSA was also greater in healthy adults (64.6 +/- 10.1 ml/min per square meter) than in either adults (35.4 +/- 8.4 ml/min per square meter) or children with
lead poisoning (19.5 ml/min per square meter). The
DMSA appeared to enter the erythrocytes of patients with
lead poisoning to a greater extent than in healthy adults. We conclude that renal clearance of
DMSA and its metabolites may be impaired and that the distribution of
DMSA in children with
lead poisoning may be different from that in adults.