FORMULATION AND DEVELOPMENT OF STABLE DOSAGE FORM OF AMLODIPINE BESYALTE AND BENAZEPRIL HYDROCHLORIDE TO OVERCOME PHYSICAL INCOMPATIBILITY

Amlodipine is a dihydropyridine calcium channel blocker with a slow onset and long duration of action. Benazepril hydrochloride is an angiotensin- converting enzyme inhibitor. But the Amlodipine besylate and Benazepril are physically incompatible drugs so there is need to keep them physically separated in dosage form. There are various approaches to overcome incompatibility. Among which the bilayer tablet is one of the novel, suitable approach and increasing attention from a variety of industries for various reasons viz. The purpose of this research is to study the physical incompatibility between Amlodipine and Benazepril, to formulate and develop the dosage form that overcome the incompatibility .the incompatibility study was carried by mixing two drugs in 1:1 and 1:2 ratio and then stored at 40 0C±0.20C and relative humidity 75%±0.5%. The samples were examined for physical changes, pH, and IR studies at particular time of intervals. Photographs of samples are taken at particular interval. From incompatibility study it was concluded that the bilayer tablet is the suitable approach to overcome the incompatibility. In the bilayer tablets physical separation is achieved by coating the Benazepril hydrochloride granules with the gelatin and then formulating bilayer tablets to minimize contact between Amlodipine besylate and Benazepril hydrochloride leads to overcome physical incompatibility. Tablets were prepared by direct compression. A 32 Full factorial design was employed to systematically optimize the drug release profile, hardness and disintegration time. The stability study conducted for optimized formulation is stable having no impact on physical incompatibility