Simvastatin is a medication used to lower blood lipid levels, particularly reducing low-density lipoprotein (LDL) cholesterol and triglycerides, while increasing high-density lipoprotein (HDL) cholesterol. This makes it suitable for patients at risk of cardiovascular diseases.

It is typically used in conjunction with lifestyle modifications, such as diet control, exercise, and smoking cessation, to manage high blood lipids in both primary and secondary hyperlipidemias.

Simvastatin also helps reduce the risk of cardiovascular complications, such as heart attacks or strokes, especially in patients with multiple risk factors like diabetes, hypertension, or a family history of heart disease.

Additionally, it is used in patients with genetically elevated blood lipids, such as heterozygous familial hypercholesterolemia (from mild to severe), to help maintain safe lipid levels.

It works by inhibiting HMG-CoA reductase, an enzyme the body needs to produce cholesterol, thereby prompting the liver to remove more cholesterol from the blood.