The objective of present study was to formulate and evaluate hydrophilic matrix tablets of Diltiazem hydrochloride achieve a controlled and sustained drug release manner with reduced frequency of drug administration, reduced side effects and improved patient compliance. Matrix tablets of Diltiazem hydrochloride were prepared using natural polymers like Xanthan Gum, Guar gu, Sodium alginate and carrageenan. All the batches were evaluated for thickness, weight variation, hardness, drug content uniformity and in-vitro drug release characteristics as per USP XXIV monograph. The release kinetics and mechanism of drug release by regression coefficient analysis and various exponential release model equations were also investigated. Tablets having xanthan gum gave more sustained release than other hydrophilic polymers studied. Amount of polymers and presence of different diluents significantly affected the drug release. It was observed that all the fabricated tablets delivered the drug following Higuchi diffusion mechanism.
