Ezetimibe is a drug that lowers cholesterol. It acts by decreasing cholesterol absorption in the intestine. It may be used alone (marketed as Zetia or Ezetrol), when other cholesterol-lowering medications are not tolerated, or together with statins (e.g., ezetimibe/simvastatin, marketed as Vytorin and Inegy) when statins alone do not control cholesterol.
Even though ezetimibe decreases cholesterol levels, the results of two major, high-quality clinical trials (in 2008 and 2009) showed that it did not improve clinically significant outcomes, such as major coronary events, and actually made some outcomes, such as artery wall thickness, worse. Indeed, a panel of experts concluded in 2008 that it should "only be used as a last resort". In one of those studies, a head-to-head trial in 2009, a much less expensive medication (extended-release niacin) was found to be superior. Ezetimibe actually increased the thickness of artery walls (a measurement of atherosclerosis) and caused more major cardiovascular events. A more positive view of the benefits of Ezetimibe is offered by Britain's NICE statement which however was published in 2007 and may not have been updated to reflect the results of the above mentioned trials
Pharmacology
Ezetimibe localises at the brush border of the small intestine, where it inhibits the absorption of cholesterol from the intestine. Specifically, it appears to bind to a critical mediator of cholesterol absorption, the Niemann-Pick C1-Like 1 (NPC1L1) protein on the gastrointestinal tract epithelial cells as well as in hepatocytes. In addition to this direct effect, decreased cholesterol absorption leads to an upregulation of LDL-receptors on the surface of cells and an increased LDL-cholesterol uptake into cells, thus decreasing levels of LDL in the blood plasmawhich contribute to atherosclerosis and cardiovascular events
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