| abstract |
The present invention describes an aqueous pharmaceutical coating formulation which can be used for coating core elements containing one or more medicaments to achieve controlled release. The coated pharmaceutical formulation provides a release of medicaments in a controlled manner at highly acidic environment such as that of stomach and shows relatively faster release in media with basic pH such as that of the intestine. The coating composition is a heterogenous mixture which comprises (a) at least 75% by weight of a water insoluble polymer which is insoluble in both acidic as well as basic pH; and (b) 1 to 25% by weight of an enteric polymer which is substantially insoluble in water at a pH below 4.5 and which is substantially soluble in water at a pH between above about 6.0, said enteric polymer and water insoluble polymer being present in an amount effective to control-the release of said medicament. The pharmaceutical composition comprises a solid medicament present in effective amounts and the coating composition thereover. |