Gemfibrozil is a prescription medication licensed to treat high triglycerides and cholesterol, as well as reduce the risk of developing coronary heart disease. It is believed to work by slowing down the liver's production of triglycerides and VLDL (very low density lipoprotein cholesterol). Gemfibrozil should be used along with diet and exercise. Some possible side effects of this drug include heartburn, upset stomach, and diarrhea.

• Lowering triglycerides in patients with hypertriglyceridemia (high triglyceride levels). Very high triglyceride levels in the body increase the risk of developing a condition known as pancreatitis (inflammation of the pancreas).

Gemfibrozil can actually cause an increase in LDL cholesterol (bad cholesterol) for people with very high levels of triglycerides (greater than 400 mg/dL). Therefore, people who have this condition in addition to high LDL cholesterol should use gemfibrozil with extreme caution or not at all.

• Reducing a person's risk of developing coronary heart disease if they have low HDL cholesterol (good cholesterol) levels in addition to high LDL cholesterol and triglycerides. Gemfibrozil should be used only if you have already tried to lower your cholesterol (and raise HDL) with diet, exercise, and other cholesterol-lowering medications.
   
• Lowering cholesterol levels in patients with hypercholesterolemia (high cholesterol). Gemfibrozil can reduce VLDL (very low density lipoprotein cholesterol), apo B (a component of cholesterol that is related to several heart disease risk factors), and, to a lesser extent, total cholesterol and LDL. Gemfibrozil also raises HDL.