CAS NO:79902-63-9 Simvastatin is available in compositionsof 20 mg and 40 mg tablet. It blocks the production of cholesterol (a type of fat) in the body. It is an HMG-COA reductase inhibitor or “statin” used to lower bad cholesterol (LDL) and triglyceride levels in your blood or to raise good cholesterol (HDL) levels in adults. This medicine is used in combination with a low-cholesterol and low-fat diet. Simvastatin may also be used in certain adolescent patients, age 10 to 17 years, who have a genetically caused cholesterol problem.