Pharmacokinetics of gold sodium thiomalate

Two normal males participated in a study designed to examine the disposition of gold given intravenously and intramuscularly as gold sodium thiomalate. Blood samples were collected for 30 days, urine and feces for ten. A triphasic decay pattern in plasma gold concentrations was observed. Terminal log-linear phases corresponded to a mean disposition half-life of 12.5 days. Absolute bioavailability of IM gold sodium thiomalate appears to be variable with one subject having complete absorption and the other absorbing 64% of the administered IM dose. The major route of elimination of an IV dose of gold sodium thiomalate is urinary excretion, with a mean of 35% of the dose found in the urine in ten days. Fecal elimination accounts for an additional 9.4% of the IV dose excreted in ten days, probably as a result of biliary secretion.