Abstract: Objective To establish a method for determining the dissolubility of metronidazole tablets in vitro, compare the dissolution curves between domestic and foreign generics to evaluate the quality consistency, investigate the quality of domestic drugs and make reference for clinical use. Methods The content of solution was determined by HPLC, and the dissolution curves were drawn. The column was Agilent TC-C18, mobile phase was methanol-water (20:80, V/V) with a flow rate of 1 mL·min^-1, detection wavelength was 320 nm, column temperature was 30°C, injection volume was 20 μL. The stirring paddle method was adopted, the dissolution mediums were water, pH=1.2 hydrochloric acid solution, pH=4.0 acetic acid-sodium acetate buffer solution, pH=6.8 phosphate buffer solution, the volume of which was 900 mL, the rotation speed was 50 rpm. The similarity of dissolution curve was evaluated by similar factor (f₂). Results The dissolution of metronidazole tablets made by all manufacturers were conformed to the requirements of the Chinese Pharmacopoeia, but the dissolution curves of generic drugs from domestic manufacturers were not similar with foreign countries’. Conclusion The quality of some domestic generics needs to be further improved. It is necessary to strengthen the supervision of generics in order to enhance the quality.

Key words: metronidazole tablet, dissolution curve, HPLC, consistency evaluation