In Vitro Dissoluion Study to Determine Drug – Drug Interaction of Atorvastatin Calcium

Abstract

Atorvastatin calcium is a selective and competitive inhibitor of HMG – CoA reductase which is responsible for converting HMG – CoA to mevalonate, a precursor of cholesterol synthesis. Thus Atorvastatin is extensively used to lower cholesterol and triglycerides in patients with hypercholesterolemia, mixed dyslipidemia Drug – Drug and Drug – Food Interaction of Atorvastatin is well established. Thus, the objective of the present research was to study and compare the dissolution profile of Atorvastatin Calcium alone and with Pantoprazole and Calcium Carbonate For the present study, Dissolution Apparatus II, USP XIII was used to conduct the experiment. Six tablet of atorvastatin alone was subjected to dissolution study followed by another six tablets of atorvastatin with six of Pantoprazole and Calcium carbonate each. Same media of phosphate buffer of pH 6.8 was used in conduction of both experiments. Then in both cases, 5 ml samples were withdrawn at time intervals of 5, 10, 15 and 30 minutes. The samples were then subjected to UV-Vis Spectroscopy and the UV absorbances were recorded.From the UV absorbances percentage dissolutions were calculated by the designated formulas. And the data of Atorvastatin alone and in combination were compared in orderto assess the changes in the dissolution profile. The changes in percentage dissolution in both cases were considerably different indicating the effect of Pantoprazole & Calcium carbonate on the dissolution profile of Atorvastatin.Bioavailability of atorvastatin is 12%. Initial Increases in dissolution profile of atorvastatin with Pantoprazole and calcium carbonate followed by a substantial decrease can lead to variable dissolution & bioavailability of atorvastatin in presence of other drugs while, also increases the risk of side – effects and toxicity of atorvastatin. Thus, further studies are needed to confirm whether, such effect on dissolution profile is beneficial or harmful