Preparation of Metformin Hydrochloride Sustained-release Tablets By Melt Granulation

OBJECTIVE To prepare metformin hydrochloride sustained-release tablets and to study its release characterization in vitro and the factors affecting drug release. METHODS Metformin hydrochloride sustained-release tablets were prepared with glycery behenate as matrix material, microcrystalline cellulose as pore-forming agent by melt granulation. The impacts of releasing transmitter, contents of glycery behenate and microcrystalline cellulose, and preparation process factors on the drug release in vitro of the tablets were studied. RESULTS The contents of glycery behenate and microcrystalline cellulose were critical factors affecting drug release rate. The tablets had a remarkable sustained-release property, the drug release profile in vitro followed zero order or Higuchi kinetics. CONCLUSION Using glycery behenate as the wax matrix materia1, combining with other filers, a sustained release tablet of once daily administration is prepared by melt granulation.