The in vitro and in vivo availability of commercial aspirin in dogs.
Dissolution rates of 11 commercial brands of aspirin was assessed in vitro using simulated gastric juice. Excedrin dissolved fastest of all the brands of aspirin, followed by Ascriptin; the slowest was Excedrin PM. In dogs dosed orally with Excedrin or Ascriptin, total plasma salicylate peaked about 2.5 hr after dosing with Excedrin and 3 hr post-dosing with Ascriptin. About 96% of the salicylate was bound to plasma proteins. The rate at which Excedrin left the plasma was different from that of Ascriptin. Plasma salicylate concentrations from Excedrin dropped to an average of 12 mg/dl in 6 hr while Ascriptin peaked and remained virtually level for more than 12 hr.
D000818:Animals; D001241:Aspirin / Q000378:metabolism*; D001682:Biological Availability; D001798:Blood Proteins / Q000378:metabolism; D004285:Dogs; D066298:In Vitro Techniques; D007408:Intestinal Absorption; D011485:Protein Binding; D012995:Solubility
D001798:Blood Proteins; D001241:Aspirin