The present study was to develop a buoyant Hydrodynamically Balanced System (BHBS) for metronidazole (MN) using different
formulations to show their effect on the floating time and in turn improving the sustained release pattern as a single unit floating
capsule. The formulated blends were prepared using physical mixing of finely pulverized ingredients including the drug .The
compatibility of different ingredients with the drug was studied using FTIR, DSC and XRPD techniques. The prepared BHBS capsules
were also evaluated for drug content, weight uniformity and in vitro drug release. The drug release from different formulations
relied on formulating ingredient, their concentrations and type of buoyant mechanism. Histopathological study. All formulations of
MN sustained the drug release compared to capsule contains only pure MN.F7 depicted the best buoyant behavior. The
histopathological study denoted a lack of metronidazole associated gastric mucosal cells injury in albino rats .The release data was
best fit to first, diffusion model except F3 depicted first order kinetics.