Abstract: The aim of the present work was to prepare and evaluate sublingual fast dissolving lms containing metoprolol tartrate-loaded niosomes. Niosomes were utilized to allow for pro- longed release of the drug, whereas the lms were used to increase the drug’s bioavailability via the sublingual route. Niosomes were prepared using span 60 and cholesterol at different drug to surfactant ratios. The niosomes were characterized for size, zeta-potential, and entrapment ef ciency. The selected niosomal formulation was incorporated into polymeric lms using hydroxypropyl methyl cellulose E15 and methyl cellulose as lm-forming polymers and Avicel as superdisintegrant. The physical characteristics (appearance, texture, pH, uniformity of weight and thickness, disintegration time, and palatability) of the prepared lms were studied, in addition to evaluating the in vitro drug release, stability, and in vivo pharmacokinetics in rabbits. The release of the drug from the medicated lm was fast (99.9% of the drug was released within 30 minutes), while the drug loaded into the niosomes, either incorporated into the lm or not, showed only 22.85% drug release within the same time. The selected sublingual lm showed signi cantly higher rate of drug absorption and higher drug plasma levels compared with that of commercial oral tablet. The plasma levels remained detectable for 24 hours following sublingual administration, compared with only 12 hours after administration of the oral tablet. In addition, the absolute bioavailability of the drug (ie, relative to intravenous administration) following sublingual administration was found to be signi cantly higher (91.06%±13.28%), as compared with that after oral tablet administration (39.37%±11.4%). These results indicate that the fast dissolving niosomal lm could be a promising delivery system to enhance the bioavailability and prolong the therapeutic effect of metoprolol tartrate.
Published online 2016 Aug 2. doi: 10.2147/DDDT.S113775