Gemfibrozil is a medication used to lower cholesterol and triglyceride levels in the blood. It belongs to the class of drugs called fibrates, and works by decreasing the production of triglycerides in the liver and increasing the elimination of triglycerides from the blood. Gemfibrozil is typically prescribed along with dietary changes and exercise for the treatment of high cholesterol and triglycerides. It is usually taken by mouth as a tablet, and the dosage and duration of treatment will depend on the individual's condition and response to the medication. Common side effects of gemfibrozil include stomach upset, nausea, vomiting, headache, dizziness, and muscle pain. It is important to discuss any potential side effects and risks with a healthcare provider before starting treatment with gemfibrozil.