LAUSR

Abstract The floating drug delivery system (FDDS) is considered as a renewable technique in the pharmaceutical technology because the dreams of increasing the stomach residence time for local or systemic effect are continuously actual for different purposes. It was studied for small weight tablet, but it is not clearly studied for the high weight tablet which may be essential for high dose drugs or when combined drugs are needed. Sodium bicarbonate was only used as a gas generating agent to give the chance to increase the weight of the drugs. Factorial experimental design was utilized to statistically analyze factors affecting tablet buoyancy. The results showed that, all factors studied and their interactions have significant effect on the buoyancy lag time. The addition method of gas generating agent has the most significant effect on the buoyancy process regardless of concentration of sodium bicarbonate used. That is due to the gas generation process is an in-organic interaction between the moieties of strong acid normally present in the stomach and the base added to the tablet during formulation. F4 is selected as an optimum formula that achieves the lowest floating lag time (7 s) through intragranular addition of gas generating agent at the highest concentration for in-vivo radiological imaging. In-vivo study in mature human gastrointestinal tract shows that the gastric residence time has extended to 4 h after swallowing the optimum floated high weight tablet at 2 h after meal. Therefore, it is advisable that, such tablet formula should be administered after standard calorific meal since such meal delays the stomach evacuation.