Pharmacokinetic study of vincamine teprosilate.

The results obtained by the authors in the pharmacokinetic study of vincamine teprosilate after oral and i.v. administration to young healthy volunteers and after oral administration to patients aged 68 to 84 years are presented. The description of the assay for each administration route is reported in the protocol. Plasma levels of vincamine teprosilate were assayed by reverse phase HPLC with spectrofluorimetric detection. The data obtained after i.v. administration made it possible to define the pharmacokinetic model and to estimate parameters. Concentration-time data were adapted to a biocompartmental open model with alpha value of 2.9080 and beta value 0.1047. In oral administration, the overlapping of the fast disposition phase and the absorption phase led to an apparent monocompartmental fit; in both young and aged volunteers, the absorption rate constants as well as the elimination rate constants were calculated. In both groups no significant differences in tmax values were found and no latency period was noticed . Cmax values were similar in both groups of patients; the lower distribution volume in aged volunteers compared to younger ones contributed to this finding. Differences in absorption rate constants in aged and young volunteers (0.53 h-1 and 0.73 h-1 respectively) are analysed. Vincamine teprosilate bioavailability after oral administration was found to be 20 +/- 5%. Possible vincamine teprosilate dose dependence kinetics are suggested.