Structure
Cholestyramine is a bile acid sequestrant composed of a cross-linked polymer of divinylbenzene and polyethylene oxide, functionalized with quaternary ammonium groups.
Chemical Formula: (C₁₂H₁₅NO)n·Cl⁻
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Mode of Action
Bile Acid Sequestration: Binds bile acids in the intestine, preventing their reabsorption.
Cholesterol Reduction: Forces the liver to convert more cholesterol into bile acids, thereby lowering blood cholesterol levels.
LDL-C Lowering: Reduces low-density lipoprotein cholesterol (LDL-C) by decreasing hepatic cholesterol synthesis.
Uses of Cholestyramine
Hypercholesterolemia: Lowers LDL-C and total cholesterol levels.
Pruritus Associated with Cholestasis: Alleviates itching by binding bile acids.
Bile Acid Diarrhea: Manages chronic diarrhea caused by bile acid malabsorption.
Fibromyalgia: Sometimes used off-label for pain management.