ExplanationIntermediate
What is the mechanism by which colestyramine lowers blood cholesterol levels despite not being absorbed from the gastrointestinal tract?
Colestyramine lowers blood cholesterol levels by binding to bile salts in the gastrointestinal tract, preventing their reabsorption. This leads to an increase in LDL receptors in the liver, which removes more LDL cholesterol from the blood. Consequently, cholesterol is converted into bile salts, depleting the body's cholesterol stores.
Key points
- Colestyramine binds irreversibly to bile salts.
- This binding prevents bile salt reabsorption in the enterohepatic cycle.
- Increased LDL receptors in the liver enhance the removal of LDL cholesterol from the blood.
- More cholesterol is converted into bile salts, lowering overall cholesterol levels.
Source:Fundamentals of Pharmacology: An Applied Approach for Nursing and Health· Drugs used to lower blood lipids· p. 468–473
Fundamentals of Pharmacology: An Applied Approach for Nursing and Health
Alan Galbraith ... [et Al.].
Second Edition · Routledge