Formulation and evaluation of atorvastatin calcium and nicotinic acid in a bilayer tablet

Journal of Pharmacy Research 01/2009;
Source: DOAJ

ABSTRACT Atorvastatin calcium (AT) is used as a dyslipidemic agent. Nicotinic acid (NA) is antihyperlipidemic agent. In the present work development of the rate controlled dosage form for the above drugs were tried the performance characteristics like release kinetics, dissolution rate, particle size of drugs and release retardant and media selection to simulate invivo conditions. Process variables such as impact of hardness, kneading time during granulation are some critical factors found during the development based in the experimental findings. Preformulation study and drug excipients compatibility study was done initially and proceeded further for the formulation according to the results of preformulation study. Wet granulation process was used for both layer of formulation. In the present study HPMC was found to play a great role in controlling release of NA from the matrix system. Accordingly it can be concluded that the final formula is a robust one and theperformance is less likely to be affected by the various factors studied.

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