Dissolution profile of nimesulide from pharmaceutical preparations for oral use

Abstract

Nimesulide belongs to the group of semi-selective COX-2 inhibitors, widely used in solid oral formulations. In the present work, we studied the influence of surfactants among other drug excipients, as well as particle size of the active substance and the effects of medium pH on the dissolution profile of nimesulide from solid pharmaceutical forms. For that purpose, four different preparations containing 100 mg nimesulide per tablet and available on the market of Bosnia and Herzegovina (labeled here as A, B, C and D) were studied. The test for the assessment of dissolution profiles of the formulations was performed in surfactant-free dissolution medium pH 7.5. The dissolution profiles were compared by calculating difference (f1) and similarity (f2) factors. Increasing of the dissolution medium pH value from 7.5 to 7.75 resulted in a significant increase of nimesulide dissolution profile from the examined formulations. Also, the results showed that particle size affects to a great extent the dissolution profile and the best results were achieved with micronized nimesulide. The presence of the surfactants among the other excipients expressed a negligible effect on the dissolution profile.