What are fibric acid derivatives (fibrates)?

Fibric acid derivatives (fibrates) are effective medications in lowering blood triglyceride levels. Fibrates lower blood triglyceride levels by inhibiting the liver production of VLDL (the triglyceride-rich lip-protein fraction), and by speeding up the removal of triglycerides from the blood. Fibrates are also modestly effective in increasing blood HDL cholesterol levels. However, fibrates are not effective in lowering LDL cholesterol. Examples of fibrates available in the United Sates include Gemfibrozil (Lopid) and fenofibrate (Tricor).

Very high triglyceride levels (usually > 1000 mg/dl) can cause pancreatitis (inflammation of the pancreas that can result in a serious an illness with severe abdominal pain). By lowering the blood triglycerides, fibrates are used to prevent pancreatitis.

Fibrates are not effective in lowering LDL cholesterol and cannot be used alone in lowering LDL cholesterol levels. However, when a high risk patient (see NCEP recommendations above) also has high blood triglyceride or low HDL cholesterol levels, doctors may consider combining a fibrate, such as fenofibrate (Tricor), with a statin. Such a combination will not only lower the LDL cholesterol, but will also lower blood triglycerides and increase HDL cholesterol levels.

Fibrates have also been used alone to prevent heart attacks especially in patients with elevated blood triglycerides and low HDL cholesterol levels. In one large study, gemfibrozil decreased the risk of heart attacks but did not affect the overall survival of persons with high cholesterol levels. For more, please read our article on Fibrates.