Design and characterization of nizatidine effervescent floating matrix tablets employing semisynthetic rate-retarding polymers

Abstract

Nizatidine effervescent controlled release floating tablets employing three grades of HPMC K4M, HPMC
K15M and HPMC K100M in four ratios (1:0.5; 1:1; 1:5 and 1:2) were prepared and evaluated. FTIR, DSC and
XRD studies on the formulations showed no interaction of nizatidine with the polymers employed in the study.
Most of the tablet formulations showed values within the official limit upon pre and post- compression
evaluation. The type of polymer affected the drug release rate and the mechanism. Polymer swelling was crucial
in determining the drug release rate flotation. A lesser FLT could be achieved by increasing the concentration
and increasing the viscosity grade of the polymer. The optimized formulation (NS6) offered best controlled
release along with floating lag time of 1.2 min and total floating time of >14 h. Good stability was observed for
3 months during accelerated stability studies. The optimized formulation NS6 employing nizatidine: HPMC
K15M in the ratio of 1:1 showed sufficient release for prolonged period, the dose could be reduced and the
possible incomplete absorption of the drug could be avoided.