DEVELOPMENT AND CHARACTERIZATION OF SUSTAINED RELEASE GASTRO-RETENTIVE FLOATING TABLETS OF AMBROXOL HYDROCHLORIDE

Abstract

Introduction: The objective of this study was to formulate floating tablets of Ambroxyl hydrochloride (AMB HCl) using the dry granulation technique to increase its bioavailability and the gastric residence time (GRT) of the dosage form. Materials and Methods:  The gastro-retentive floating tablets of Ambroxol hydrochloride (AMB HCl) were prepared by direct compression method using different concentrations of polymers such as HPMC K4, HPMC K15 and PVP K30, gas releasing agents (Sodium bicarbonate and citric acid) and diluents (Microcrystalline cellulose). Citric acid was also used as an antioxidant.  The final mixing was done by adding talc and magnesium stearate to the granules.  Results and Discussion: The prepared formulation of AMB HCl was evaluated by some evaluation parameters such as hardness, friability, weight variation, buoyancy lag time, drug contents, total floating time, in vitro dissolution study, drug release study etc. The result from the FT-IR data study of formulation it was disclosed that there is no interaction between the drug and excipients. In the FT-IR study, it was revealed that there is no interaction between the drug and excipients. The formulation containing the combination of HPMC K 15M polymer and Sodium bicarbonate shows a good drug release pattern with less floating lag time and good floating duration. In vitro drug release study of the prepared formulation (gastro retentive floating tablets of AMB HCl) was shown that the formulation F5 was the best formulation which was found to be 99.87% drug release. The release mechanism and its kinetics were evaluated by plotting various mathematical models of release data such as the Higuchi model, Korsmeyer model, First order and Zero order drug release. The optimized formulation showed no significant change at various evaluation parameters such as hardness, friability, weight variation and % drug release for accelerated stability condition at 40±2^oC temperature and 75±5% (RH) relative humidity for 3 months.   The floating tablets of AMB HCl showed their potential over a prolonged period as a gastro retentive drug delivery system (GRDDS).