What is the primary action of fibric acid derivatives in treating hyperlipidemia?

Fibric acid derivatives, also known as fibrates, primarily act to lower triglyceride levels in patients with hyperlipidemia. They achieve this by activating peroxisome proliferator-activated receptors (PPARs), particularly PPAR-alpha. This activation leads to increased oxidation of fatty acids in the liver and muscles, which promotes the breakdown of triglycerides. Additionally, fibrates decrease the hepatic production of triglycerides and enhance the clearance of triglyceride-rich lipoproteins, thus effectively lowering circulating triglyceride levels.

While fibrates can also have a positive effect on high-density lipoprotein (HDL) cholesterol, their most significant and clinically relevant action is their ability to lower triglyceride levels, making them particularly useful in conditions where triglyceride levels are elevated. This distinctive mechanism differentiates fibrates from other lipid-lowering agents, such as statins, which primarily focus on reducing low-density lipoprotein (LDL) cholesterol.