Objective: The objective of the present study was to prepare mucoadhesive in situ nasal gels with mucilage isolated from hibiscus flower (Hibiscus rosa sinesis, family: malveceae) containing alprazolam. Methods-Nasal gels of alprazolam were prepared using three different concentration (0.5%, 1% and 1.5% w/v) of H Rosa mucilage (HRM) and synthetic polymers (Hydroxy propyl methyl cellulose and carbopol 934). In situ gels were prepared with mixture of pluronic F127 and mucoadhesive agent. Result: Evaluation of HRM showed that it was as safe as the synthetic polymer for nasal administration. Evaluation of the prepared gel was carried out, including determination of viscosity, texture profile analysis and mucoadhesive strength. In vitro drug permeation study was conducted with the gels prepared with and without permeation enhancer (0.5% w/v sodium taurocholate) using excised goat nasal mucosa. For the determination of any further histological changes, before and after in vitro permeation study of the gels, with and without the permeation enhancer was also conducted. In vivo experiment conducted in rabbits further confirms that in situ nasal gel prepared with HRM provided better bioavailability of alprazolam than the gels prepared from synthetic mucoadhesive polymer. Conclusion: It was observed that the nasal gel containing 0.5% HRM and 0.5% sodium taurocholate exhibited appropriate rheological, mechanical and mucoadhesive properties and showed better drug release profile. More over this formulation produced no damage to the nasal mucosa used for the permeation study, and absolute bioavailability was also higher compare to gels prepared from synthetic polymers.
Key word: Alprazolam, Mucoadhesive agent, Nasal gel, Hibiscus rosa.