Bile acid sequestrant acid reabsorption will decrease cholesterol levels, in particular, low-density lipoprotein (commonly known as "bad cholesterol") in blood. Consequently, these drugs have been used for the treatment of hypercholesterolemia and dyslipidemia. Use of these agents as hypolipidemic agents has decreased markedly since the introduction of the statins, which are more efficacious than bile acid sequestrants at lowering LDL. They are occasionally used as an adjunct to the statins as an alternative to the fibrates (another major group of cholesterol-lowering drugs), which are thought to increase the risk of rhabdomyolysis when used with statins. The bile-acid-binding resins can raise triglycerides modestly (about
Discovery and development of statins is needed for normal cell function and inhibition in non-hepatic cells could possibly be harmful. The essential structural components of all statins are a dihydroxyheptanoic acid unit and a ring system with different substituents. The statin pharmacophore is modified hydroxyglutaric acid component, which is structurally similar to the endogenous substrate HMG CoA and the mevaldyl CoA transition state intermediate (Figure 1). The statin pharmacophore binds to the same active site as the substrate HMG-CoA and inhibits the HMGR enzyme. It has also been shown that the HMGR is stereoselective and as a result all statins need to have the required