What is the primary action of fibric acid derivatives in lipid lowering?

Fibric acid derivatives, also known as fibrates, primarily function by decreasing triglyceride levels. They work mainly by activating peroxisome proliferator-activated receptors (PPARs), particularly PPAR-alpha, which leads to an increase in the oxidation of fatty acids in the liver and muscle tissues. This mechanism significantly reduces triglyceride synthesis and enhances the clearance of triglyceride-rich lipoproteins from the circulation.

While fibrates can have some effect on increasing HDL cholesterol and may modestly decrease LDL cholesterol levels, their primary and most clinically relevant action is the reduction of triglyceride levels. Hence, the specific focus on triglyceride reduction is what identifies the primary action of fibric acid derivatives in lipid-lowering therapy.