What is the recommended dosage and use of cholestyramine for treating high cholesterol or liver disease-related conditions?

Cholestyramine Dosage and Use for High Cholesterol and Liver Disease

For treating high cholesterol or liver disease-related conditions, cholestyramine is recommended at a dosage of 4 g up to four times daily (16 g/day total) for high cholesterol, while for hepatic pruritus it is considered a second-line treatment after rifampicin at a dosage of 9 g daily. 1, 2

Dosing for Hypercholesterolemia

• The recommended starting adult dose is 4 g (one 9-gram pouch or scoop of powder contains 4 g of anhydrous cholestyramine resin) once or twice daily 2
• Maintenance dose is 8-16 g daily (2-4 pouches/scoops) divided into two doses 2
• Dose increases should be gradual with lipid level assessment at intervals of at least 4 weeks 2
• Maximum recommended daily dose is 24 g of anhydrous cholestyramine resin (6 pouches/scoops) 2
• Administration is recommended at mealtime, but can be modified to avoid interference with other medications 2

Administration Instructions

• Cholestyramine should never be taken in dry form 2
• Mix with at least 2-3 ounces of water or other non-carbonated beverage 2
• Can also be mixed with highly fluid soups or pulpy fruits with high moisture content 2
• Other medications should be taken at least 1 hour before or 4-5 hours after cholestyramine to avoid impeding their absorption 1

Use in Liver Disease

• For hepatic pruritus, cholestyramine is considered a second-line treatment after rifampicin in current guidelines 1
• Earlier guidelines recommended cholestyramine as first-line therapy at 4 g up to four times daily 1
• One small double-blinded RCT showed benefit with cholestyramine 9 g daily for hepatic pruritus 1
• When used with UDCA (ursodeoxycholic acid) in cholestatic liver diseases, administration should be separated by at least 4 hours to prevent binding and loss of efficacy 1, 3

Efficacy

• For hypercholesterolemia: Monotherapy provides approximately 10-15% reduction in LDL-C 1
• In combination with low to moderate-intensity statins: Additional 10-16% reduction in LDL-C 1
• For hepatic pruritus: Evidence is limited but shows some benefit in small studies 1
• In children with Alagille syndrome (a cholestatic liver disease), cholestyramine showed no significant effect on serum lipid profile even at doses up to 500 mg/kg/day 4

Contraindications and Precautions

• Contraindicated in complete biliary obstruction and history of serious hypersensitivity 1
• May increase triglycerides and cause acute pancreatitis - monitor triglyceride levels 1
• May cause GI obstruction - avoid in patients with gastroparesis or other GI motility disorders 1
• May cause vitamin K or fat-soluble vitamin deficiencies - oral vitamins should be given ≥4 hours before cholestyramine 1
• Can cause hyperchloremic metabolic acidosis, especially in patients with volume depletion, renal failure, or those taking spironolactone 5

Monitoring

• Monitor lipid/lipoprotein levels at intervals of not less than 4 weeks 2
• Monitor for common side effects, particularly gastrointestinal symptoms 1, 6
• In patients with liver disease, monitor fat-soluble vitamin levels 1
• For patients on warfarin, monitor INR frequently during initiation and then periodically 1

Special Considerations for Liver Disease

• In patients with compensated liver cirrhosis, cholestyramine has been shown to have a reduced effect on bile acid synthesis compared to healthy controls, suggesting decreased hepatic reserve 7
• For patients with chronic cholestatic liver disease who also have hypercholesterolemia, cholestyramine may serve dual purposes of treating both pruritus and elevated cholesterol 8