Pharmacokinetics and bioequivailence of mestinon sustained-released tablets in rabbits

Aim To study the pharmacokinetics and bioequivalence of mestinon sustained-release tablets after a single and multiple oral dose in healthy rabbits in order to provide the basis for clinical research.Methods A randomly,two-period crossover design was used in this study.A single dose and multiple oral doses of mestinon sustained-release and common tablets were given to 6 rabbits,respectively.Results The main pharmacokinetic parameters after a single dose administration of mestinon sustained-release and common tablets were as follows: Tmax(6 ± 0) and(2 ± 0) h;Cmax(14.446 ± 0.279) and(17.944 ± 0.919) μg.L-1;T 12(5.449 ± 2.779) and(2.733 ± 0.652) h;AUC0-t(231.076 ± 4.408) and(196.127 ± 4.009) μg.h.L-1;AUC0-∞(254.644 ±6.49) and(198.385 ± 3.934) μg.h.L-1.The relative bioavailability of sustained-release tablets was(117.3 ± 11.0) %.The pharmacokinetic parameters of multiple doses study were as follows: Cmax(18.391 ± 0.16) and(25.477 ± 0.177) μg.L-1;Cmin(3.421 ± 0.186) and(6.612 ± 0.254) μg.L-1;Cav(12.99 ± 0.055) and(16.088 ± 0.132) μg.L-1;AUCss(155.881 ± 0.655) and(193.057 ± 1.591) μg.h.L-1;DF(1.152 ± 0.012) and(1.173 ± 0.019).The relative bioavailability of the sustained-release tablets was(106.7 ± 6.4) %.Conclusion Sustained-release and common tablets are bioequivalents,and sustained-release tablets of mestinon has the characteristics of sustained release.