Studies on Pharmacokinetics and Relative Bioavailability of Neostigmine Bromide Sustained-Released Tablets in Rabbits

OBJECTIVE To study the pharmacokinetics and relative bioavailability of neostigmine bromide sustained-release tablets and conventional tablets in rabbits.METHODS Single dose of 45 mg neostigmine bromide sustained-release tablets or conventional tablets was orally given to 6 rabbits in a randomized crossover study.The neostigmine bromide concentration in plasma was determined by high performance liquid chromatography,and the pharmacokinetic parameters and relative bioavailability were calculated.RESULTS The main pharmacokinetic parameters for the sustained-release tablets and conventional tablets were as the follows: tmax(7.00 ±1.09)and(1.58±0.38)h;ρmax(3.42±1.14)and(4.56±1.72)mg·L-1;AUC0-∞(52.97±13.43)and(59.78±12.34)mg·h·L-1.The relative bioavailability of the sustained-release tablets to conventional tablets was(93.3± 24.6)%.CONCLUSION The sustained-release tablets of neostigmine bromide have significant sustained-release property,the variance analysis showed no significant difference in absorption between the test and reference formulations.