Development and Characterization of Buccal Tablets of Metformin Hydrochloride Using Mucoadhesive Polymers

The present study was aimed at the development and characterization of mucoadhesive buccal tablets of
Metformin Hydrochloride using different mucoadhesive polymers to achieve sustained drug release and improved
patient compliance. Buccal tablets were prepared by direct compression method employing hydroxypropyl
methylcellulose (HPMC K4M), carbopol 934P, sodium carboxymethyl cellulose, and polyvinylpyrrolidone as
mucoadhesive polymers. The prepared formulations were evaluated for precompression parameters including
angle of repose, bulk density, tapped density, Carr's index, and Hausner ratio. Post-compression evaluation
included hardness, friability, thickness, weight variation, drug content uniformity, surface pH, swelling index,
mucoadhesive strength, and in vitro drug release study. The results demonstrated that all formulations possessed
satisfactory flow properties and complied with pharmacopoeial limits for physicochemical parameters. The
surface pH values were found near neutral, indicating compatibility with buccal mucosa. Swelling index and
mucoadhesive strength increased with increasing polymer concentration. In vitro drug release studies revealed
sustained release behavior of metformin hydrochloride over an extended period. Among all formulations,
formulation F5 exhibited optimum mucoadhesive properties and prolonged drug release profile due to higher
polymer concentration. The study concluded that mucoadhesive buccal tablets of metformin hydrochloride could
be considered a promising alternative to conventional oral dosage forms for sustained drug delivery and improved
therapeutic efficacy in the management of Type 2 Diabetes Mellitus.
Keywords: Metformin hydrochloride; Buccal tablets; Mucoadhesive polymers; Sustained drug release; Buccal
drug delivery system; Direct compression; Mucoadhesion; Controlled release