METRONIDAZOLE BIOADHESIVE VAGINAL SUPPOSITORIES: FORMULATION, IN VITRO AND IN VIVO EVALUATION Research Article

Drug administration via mucosal membranes, including the vaginal, has the advantage of by passing the hepatogastrointestinal first pass metabolism associated with oral administration. Metronidazole suppositories were prepared using different suppository bases viz., water soluble bases ( PEGs and gelatin ) emulsion and fatty bases. The physicochemical properties of most of the prepared MTZ suppositories comply with the pharmacopoeial limits and passed the quality control tests. In general, water soluble suppository bases gave higher release than did the emulsion in citrate buffer pH 4. PEG base (F14), gelatin base (Fl8) and emulsion base (F23) gave the highest drug release and selected for further investigation. The release of MTZ from polyethylene glycol bases followed, first and Higuchi order release model, while gelatin and emulsion obeyed first model. The tested suppository showed enhancement of drug absorption from tested suppository and the One way ANOVA analysis for AUC(0-∞) showed that the P value is 0.0502, considered not significant. The microbiological results showed that the bioadhesive formulae that released the concentration of 0.25 mg/ml of the drug and sustained this concentration for 120 min can be effective on C. albicans moreover bioavailability study was performed on flagyl ® vaginal suppository (market product) and the prepared pluronic127 –cp934 bioadhesive vaginal gel ,eight female rabbits were randomly divided into two groups, each containing four rabbits the results showed that the tested formulae did not exhibit enhancement in bioavailability in comparison to the market product which mean lower side effects and localized effect inside the vagina.