What is the class of lipid-lowering agents that works by binding bile acids?

Bile acid sequestrants are a specific class of lipid-lowering agents that function by binding to bile acids in the gastrointestinal tract. When these agents bind bile acids, they prevent their reabsorption in the intestines, leading to increased excretion of bile acids through feces. This process forces the liver to compensate for the reduced bile acid levels by converting more cholesterol into bile acids, thus lowering the overall cholesterol levels in the bloodstream.

This mechanism is distinct from that of statins, which inhibit HMG-CoA reductase to decrease cholesterol synthesis in the liver, and fibrates, which primarily act by activating peroxisome proliferator-activated receptors (PPARs) to enhance lipid metabolism and lower triglyceride levels. Likewise, PCSK9 inhibitors function by inhibiting the protein PCSK9, which prevents the degradation of LDL receptors, thus increasing the clearance of LDL cholesterol from the bloodstream.

Therefore, bile acid sequestrants are uniquely characterized by their direct binding action, making this class essential for specific therapeutic approaches to managing cholesterol levels.