Coronary heart disease is the most prevalent form of cardiovascular disease in the United States. Hyperlipidemia--specifically, increased total and low-density lipoprotein cholesterol levels--positively correlates with the development of coronary heart disease. Colesevelam, a nonabsorbed, water-insoluble polymer, is a new bile acid sequestrant that is effective in lowering total and low-density lipoprotein cholesterol levels. In several short-term, placebo-controlled studies, colesevelam has decreased total cholesterol levels by approximately 6 to 10% and low-density lipoprotein cholesterol levels by approximately 9 to 20%. When given in combination with atorvastatin, lovastatin, or simvastatin, low-density lipoprotein cholesterol levels were decreased more than with colesevelam alone. Its unique hydrogel formulation may also minimize the potential for gastrointestinal adverse effects, which are common with other bile acid sequestrants. There have been few published studies available concerning this drug; no long-term studies and few large-scale studies have been published.