Cholestyramine is indicated for:

• treatment of elevated serum cholesterol as an adjunct to diet and exercise in patients with primary hypercholesterolemia (elevated LDL-cholesterol)

  
  

• treatment of pruritus associated with partial biliary obstruction

  
  

• treatment of diarrhea associated with excess fecal bile acids due to short bowel syndrome
  

Indications not approved by Health Canada: Cholestyramine has been used in the treatment of pruritus associated with partial biliary cirrhosis and in the treatment of diarrhea associated with pseudomembranous colitis, erythroprotoporphyria and hyperoxaluria. It has also been used in the removal of drugs (e.g. cardiac glycosides) or toxins (heptachlor, a pesticide) from the gastrointestinal tract, including removal of drugs that undergo enterohepatic recycling, a technique that effectively lowers the terminal elimination half-life of drugs with very long half-lives (e.g. leflunomide).

Bile acid sequestrants are alternatives to HMG-CoA reductase inhibitors (statins) for the treatment of hypercholesterolemia. At a daily dose of 8 to 10 g/day, cholestyramine reduces LDL-cholesterol concentrations by 10-20%. The LDL-lowering properties of bile acid sequestrants, including cholestyramine, are additive to those of other cholesterol-lowering drugs. The addition of a bile acid sequestrant to a statin can produce a 12% to 16% reduction in LDL cholesterol beyond that achieved with a statin alone. The LDL-cholesterol-lowering activity of 4 g of cholestyramine is estimated to be equivalent to 5 g of colestipol, another bile acid sequestrant.

Treatment with bile acid sequestrants may increase plasma triglyceride concentrations; therefore these agents should not be used alone in patients with hypertriglyceridemia.