Objective: The current research involves the formulation of a sustained-release gastro-retentive drug delivery system of nizatidine. Methods: Using 33 Box-Behnken designs, about 17 experiments were performed and evaluated for various parameters like physical appearance, pH, in vitro gelling study, in vitro buoyancy study, measurement of viscosity, density measurement, gel strength, raft resilience, drug content, acid neutralization capacity, in vitro dissolution, release kinetics and stability studies. Results: All the formulations exhibited good viscosity, density less than gastric fluid, gelling capacity retained, and buoyant for 12 h. Drug content ranges from 97.98 to 99.34 %, with a long neutralization period. The buoyancy lag time was found to be in the range of 15.34 to 26.12 sec and the % drug release at 12 h was between range from 85.67 to 99.45, with the highest release exhibited by F3. All formulations displayed zero order in vitro drug release>10 h with exceptional buoyancy properties. F3 was the optimized formulation and further subjected to FTIR and DSC study, concluding that compatibility of nizatidine with excipients in the formulation blend. Stability studies show no significant changes. Conclusion: Results indicate that gastric-floating formulations of nizatidine have the prospective for superior gastric residence time and sustained drug release.

Objective: The current research was aimed to formulate and evaluate raft forming gastro retentive floating drug delivery systems of Lafutidine for improving gastric residence time and sustained drug release for an extended time. Methods: Using Box–Behnken experimental design 17 formulations of lafutidine GRDDS were designed and evaluated for various parameters like physical appearance, pH, In vitro gelling study, in vitro buoyancy study, measurement of viscosity, density measurement, gel strength, drug content, acid neutralization capacity, the profile of neutralization, in vitro dissolution, release kinetic and stability studies. Results: All the evaluations were performed and observed that the values were within range, and the buoyancy lag time ranged within 14.76 to 25.84 sec and the formulations remained buoyant for more than 8h with the gelling time of 12h, the drug content was ranging from 98.96 to 99.55 %, and in vitro release was 86.86 to 99.34% by the end of 12h. The release kinetics followed zero-order with Higuchi’s model that indicating that drug release was found to be followed by the matrix diffusion process. Conclusion: Out of all formulations F3 was the optimized formulation and it was further characterized for FTIR, DSC, and stability studies, which exposed that there were no interactions amongst drug and excipients and no major change in the formulation and found to be stable.

Objective: The present research work is focused to develop in situ raft gel of lafutidine. Sodium alginate is one of the critical components for the development in situ raft system. Methods: The formulation was prepared using hydrophilic polymers such as ethyl cellulose, HPMC K4M, and chitosan. The formulations were subjected to evaluation characteristics such as pH, in vitro gelling time, viscosity, density, gel strength, drug-polymer compatibility studies, drug content floating lag time, swelling index, and in vitro release studies. Results: The pH of all the prepared batches was found in the range of 5.7 to 7.6. All the prepared formulations showed viscosity in the range of 264 to 320 cps, with gelling time from 4-7 s. For F1-F15 batches Floating lag time was found to be in the range of 9-24 sec. Densities of all formulations stomach specific in situ gels were in the range of 0.4 to 0.8 gm/cm3. The highest swelling index was observed in F15 with 14.16% Highest gel strength is exhibited by F15; all the formulations were in the range of 95.46–99.95, indicating the uniform distribution of the drug. Formulation F15 containing chitosan in combination with ethyl cellulose gave the highest drug release of 99.78% and also showed sustained and controlled release for up to 24h. Conclusion: F15 shows an R2 value of 0.999. As its value is nearer to the ‘1’ it is confirmed as it follows the Zero order release with an ‘n’ value is 1.5021 for the optimized formulation (F15) i.e., the n value indicates super case II transport and is considered as optimized formulation.

The aim of any research work is to find the complications associated with the drug or formulation and find the conclusion of what can be the best possible way to solve them. It has been observed that drugs with short half-life, pH-dependent solubility and having absorption window in upper part of GIT forms good drug candidate for gastro retentive system. Since the formulation reside at a particular site and releases the drug in a controlled manner. In this review article, we have focussed on a thorough understanding on the gastric region, which helped in selecting drugs, various types of gastro retentive systems, new outcomes from recent literature, and important evaluation parameters to attain formulation objective and various marketed products available.