Simvastatin (Zocortrade mark, Merck) is a safe and effective 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitor. Simvastatin potently lowers total and low density lipoprotein (LDL) cholesterol. Simvastatin was the first cholesterol-lowering agent that reduced total mortality in a randomised clinical trial. Simvastatin is effective at reducing total mortality, myocardial infarction, coronary mortality and the incidence of stroke or transient ischemic attack in patients with coronary heart disease and hypercholesterolemia. Simvastatin, like other statins, also has non-lipid mechanisms of action. These include anti-inflammatory effects, antiproliferative effects on smooth muscle cells and an upregulation of endothelial nitric oxide synthase. Overall, simvastatin has an excellent safety profile. Simvastatin, along with other statins, has made a significant impact on the morbidity and mortality from coronary heart disease.