Dual acting oral floating matrix tablets of ranitidine hydrochloride.

ABSTRACT

The main purpose of this work was to prepare floating matrix drug delivery system of Ranitidine. Floating matrix tablets of Ranitidine were developed to prolong gastric residence time and increase its bioavailability. Rapid gastrointestinal transit could result in incomplete drug release from the drug delivery system above the absorption zone leading to diminished efficacy of the administered dose. Floating matrix tablets containing 100 mg Ranitidine were developed using different effervescent salts and polymer combinations. The tablets were prepared by direct compression technique, using polymers such as hydroxyl propyl methyl cellulose (HPMC K4M), Carbopol 934 in combination. Sodium bicarbonate, citric acid, calcium carbonate was incorporated as a gas-generating agent. The effects of sodium bicarbonate on drug release profile and floating properties were investigated. The formulation was optimized on the basis of acceptable tablet properties, floating lag time, total duration of floating and in vitro drug release. The formulated tablets with optimum hardness, uniform thickness, consistent weight uniformity and low friability. The results of dissolution studies, floating lag time indicated that formulations F4 exhibited good and controlled drug release. Applying the linear regression analysis and model fitting showed the selected formulation F4 showed diffusion coupled with erosion drug release mechanism, followed first order kinetics. Optimized floating matrix tablets F4 showed no change in physical appearance, drug content, or in dissolution pattern after storage at 250C/ relative humidity 65% and 40°C / relative humidity 75% for a period of 3 months.