What does cholestyramine powder treat?

From the Guidelines

Cholestyramine powder is used to treat high cholesterol levels and pruritus (itching) associated with bile acid accumulation, primarily by binding to bile acids in the intestine and promoting their elimination through stool, as stated in the 2022 study by the American College of Cardiology 1.

Key Points

• Cholestyramine powder works by binding to bile acids in the intestine, preventing their reabsorption and promoting their elimination through stool, which helps lower LDL ("bad") cholesterol levels in the blood.
• The typical dose ranges from 8-16 g/day orally, divided into 2 doses, as recommended in the study by the American College of Cardiology 1.
• Cholestyramine is also used to manage diarrhea caused by bile acid malabsorption and can help remove certain drugs or toxins from the body through its binding properties.
• When taking cholestyramine, it's essential to separate it from other medications by at least 4 hours, as it can interfere with their absorption, as noted in the study by the British Society of Gastroenterology 1.
• Common side effects include constipation, bloating, and gas, and adequate fluid intake is recommended while using this medication to minimize digestive discomfort.

Treatment of Pruritus

• Cholestyramine is often used as first-line therapy for pruritus associated with parenchymal liver disease, although the evidence is limited, as stated in the 2018 study by the British Journal of Dermatology 1.
• The dose of cholestyramine for pruritus can range from 4-16 g/day, and it's essential to start with a low dose and titrate gradually to minimize side effects, as recommended in the 2020 study by the Canadian Association of Gastroenterology 1.

Important Considerations

• Cholestyramine can impair the absorption of various medications, such as UDCA, and should be given 2-4 hours before or after other medications, as noted in the study by the British Society of Gastroenterology 1.
• Patients with a history of serious hypersensitivity to cholestyramine should avoid using this medication, and those with bowel obstruction or history of hypertriglyceridemia-induced pancreatitis should use it with caution, as stated in the study by the American College of Cardiology 1.

From the FDA Drug Label

Cholestyramine for Oral Suspension, USP powder is indicated as adjunctive therapy to diet for the reduction of elevated serum cholesterol in patients with primary hypercholesterolemia (elevated low density lipoprotein [LDL] cholesterol) who do not respond adequately to diet Cholestyramine for Oral Suspension, USP powder may be useful to lower LDL cholesterol in patients who also have hypertriglyceridemia, but it is not indicated where hypertriglyceridemia is the abnormality of most concern

Cholestyramine powder treats:

• Primary hypercholesterolemia (elevated low density lipoprotein [LDL] cholesterol)
• May be useful to lower LDL cholesterol in patients with hypertriglyceridemia (but not as primary treatment for hypertriglyceridemia) 2

From the Research

Conditions Treated by Cholestyramine Powder

Cholestyramine powder is used to treat several conditions, including:

• Primary hypercholesterolemia and hypercholesterolemia associated with mild hypertriglyceridemia, in patients not responding to dietary treatment 3
• Pruritus associated with cholestatic disease, in patients with incomplete biliary obstruction 3
• Diabetes mellitus, as modulation of bile acid homeostasis has a good clinical effect in managing the condition 3
• Diarrhea from bile acid malabsorption, as cholestyramine can help manage the condition by binding to bile acids in the intestine 3
• Hyper-LDL-cholesterolemia, although it is not the first choice of treatment, as statins are preferred due to their strong LDL-C lowering effects and efficacy in prevention of cardiovascular disease 4

Mechanism of Action

Cholestyramine works by binding to bile acids in the intestine to form an insoluble complex, which is excreted in the feces, thereby reducing the amount of bile acids available for reabsorption into the bloodstream 3, 5. This leads to an increase in the production of new bile acids from cholesterol, which in turn reduces the amount of cholesterol available for incorporation into low-density lipoproteins (LDL) 6, 7.

Effects on Lipid Metabolism

Cholestyramine treatment has been shown to:

• Lower total plasma cholesterol levels, mainly due to a reduction in LDL cholesterol 7
• Increase plasma triglyceride levels, reflecting enhanced very low-density lipoprotein (VLDL) triglyceride concentrations 7
• Stimulate cholesterol 7 alpha-hydroxylase, the rate-limiting enzyme in bile acid synthesis, and increase HMG-CoA reductase activity and LDL receptor expression in the liver 6