Different types of cholesterol reducers affect levels of fats (lipids) in different ways and generally fall into the following categories:

• Statins. Considered the first line of treatment for most patients with high cholesterol (hypercholesterolemia), statins block the production of specific enzymes used by the body to make cholesterol. Statins have been shown to reduce the risk of a first heart attack, as well as recurrent heart attacks in patients with known disease, and stroke. They have also been shown to reduce the risk of death among patients with heart failure. Statins are particularly effective at lowering levels of LDL (“bad”) cholesterol and, to a lesser degree, triglycerides. While statins do increase levels of HDL (“good”) cholesterol, they do not seem to increase those levels as well as other cholesterol reducers do. Statins generally have limited side effects, although there are some reports of a rare muscle deterioration called rhabdomyolysis. Some media reports have also linked statins to reduced memory function, but this appears to be a rare side effect. Periodic blood testing is advisable to monitor both the side effects on blood fats and to monitor liver function. 
  
  The decision to administer statins depends on multiple clinical considerations including the total cholesterol levels, LDL levels, HDL levels, history of previous myocardial infarction and other risk factors for coronary artery disease, particularly diabetes. Statins have been shown to have a favorable effect on the arteries irrespective of the degree of cholesterol lowering achieved. This effect is believed to be through an anti-inflammatory action resulting in stabilization of atherosclerotic plaque. Because of this, some studies have suggested that intensive, immediate statin therapy may be initiated for patients who are hospitalized with coronary artery disease.
  
  
• Bile acid resins. Because the liver takes cholesterol out of the blood to make bile, bile acid resins prevent the recycling of bile acids in the intestine. As a result, the liver is forced to remove more cholesterol from the blood in order to manufacture more bile. Bile acid resins are usually taken in powder form or in a chewable bar. Many patients, however, have gastrointestinal discomfort with these drugs. Bile acid resins are also known to bind to other substances, such as fat-soluble vitamins, the heart drug digoxin and the anticoagulant warfarin. It is not recommended that patients take these drugs at the same time they are taking bile acid resins.
  
  
• Nicotinic acid (niacin), a form of vitamin B3. In large doses, nicotinic acid is very effective in lowering triglyceride levels and raising levels of HDL (“good”) cholesterol. Nicotinic acid can also lower levels of LDL (“bad”) cholesterol, but not as effectively as other cholesterol reducers. When taking niacin, patients are advised to slowly build up to the high doses needed to treat high cholesterol. Taking too much niacin can lead to intense side effects that include flushing, palpitations, nausea and, in extreme cases, liver toxicity (especially when taken in “rapid-release” form). Even with proper build-up, as many as 50 percent of patients find the side effects of this medication too difficult to tolerate. Nicotinic acid is available over the counter, but physicians prefer to prescribe it in time-released pills. Because of the potentially intense side effects, patients should never begin taking niacin without the supervision of a physician. Additionally, many of the "no flush" niacin dietary supplements sold over the counter do not affect blood lipid levels.
  
  
• Fibrates (or fibric acid derivatives). Fibric acid reduces the production of triglycerides and increases the rate at which existing triglycerides are removed from the bloodstream. Fibrates can significantly lower triglyceride levels and modestly increase HDL (“good”) cholesterol levels in most patients, but they are less effective at reducing LDL (“bad”) cholesterol levels. They are most commonly used in patients who have elevated triglyceride levels, usually in conjunction with low HDLs (many diabetics have this type of lipid profile). Simultaneous use of fibrates and statins should be carefully monitored. 
  
  
• Ezetimibe. Ezetimibe is a newer class of cholesterol drug that blocks cholesterol absorption in the small intestine. It has been shown to reduce LDL cholesterol levels, although not as much as statins. Ezetimibe has been marketed alone and combined with statin drugs. The drug class was approved by the U.S. Food and Drug Administration in 2004, but a clinical study released in 2008 indicated that ezetimibe alone or in combination provided no benefits that could not be achieved with a statin drug. One specific measure in the study (the thickness of plaques in carotid arteries) did not improve at all and, in some cases, appeared worsened by the drug.

Examples of these medications* include the following: