Bioavailability/or Bioequivalence and Disposition Kinetic studies play an important role during the process of drug development and it applies to both new drugs as well as to their generic counterparts. These studies are also used for the post approval process due to changes done in manufacturing of drugs and to ensure the availability of safe and effective medicine to the patients. The most familiar class of Antihyperlipidemic drugs is statins which reduce the plasma cholesterol level by blocking the cholesterol synthesis and Atorvastatin is being used frequently to treat cholesterol related disorders.