Brain and blood levels of bismuth after oral or parenteral administration of tripotassium-dicitrato bismuthate to rats.

Bismuth levels in blood and brain of rats have been measured following acute or subchronic administration of tri-potassium-dicitrato bismuthate (TDB) by intraperitoneal injection or by gavage. After parenteral administration, the presence of bismuth in blood was associated with appreciable bismuth concentrations in brain of treated animals (approximately equal to 10-30% of blood levels). In contrast, following oral treatment, no bismuth was detected in brain of animals, even at doses of TDB able to produce blood bismuth concentrations comparable with those obtained after intraperitoneal administration. The formation of different bismuth species in blood of treated animals depending upon the route of administration of TDB is suggested.