Aim The
pharmacokinetics and relative
bioavailability of domestic film_coating special shaped tablet of acetaminophen were
studied.Methods A single oral dose of 500 mg of the two formations (test and reference preparation) was given to 10 healthy male volunteers according to randomized 2_way cross_over design, blood sample was withdrawn 10 hours after administration, and plasma concentrations of acetaminophen were assayed by a high performance liquid chromtography (HPLC) method. Results The concentration_time curves of the two preparations fitted to a one_compartment model with first order absorption and lag time. The main pharmacokinetic parameters of the tested preparation were as follows:Cmax=5.51±1.24 mg/L, Tpeak=1.03±0.43 h, T 1/2ka=0.27±0.16 h, T1/2ke=2.60±0.51 h,AUC0?t=23.69±4.08 mg·h·L-1,MRT=3.65±0.22 h. Conclusion The relative
bioavailability of the test preparation is 102.5±13.3% to the reference preparation . The bioavailabity of the two kinds of acetaminophen is equal , showing that the two kinds of preparations are bioequivalent preparations.