Lipitor (atorvastatin) is a statin drug that is commonly used to lower cholesterol levels. Statins are a class of drugs that work by blocking an enzyme in the liver that is responsible for producing cholesterol. By blocking this enzyme, statins can reduce the amount of cholesterol in the bloodstream, which can help to lower the risk of heart disease and stroke [2].

Lipitor is one of the most widely prescribed statins in the United States, and it has been shown to be highly effective at lowering cholesterol levels. In fact, studies have shown that Lipitor can lower LDL (bad) cholesterol levels by up to 60%, which is significantly more than other statins like simvastatin [3].

Simvastatin is another statin drug that is commonly used to lower cholesterol levels. Like Lipitor, simvastatin works by blocking the enzyme that produces cholesterol in the liver. However, simvastatin is generally considered to be less effective than Lipitor at lowering cholesterol levels. Studies have shown that simvastatin can lower LDL cholesterol levels by up to 45%, which is significantly less than Lipitor [3].

Overall, while both Lipitor and simvastatin are effective at lowering cholesterol levels, Lipitor has been shown to be more effective than simvastatin. However, it is important to note that the choice of medication will depend on a number of factors, including the patient's medical history, current medications, and other health conditions. It is important to speak with a healthcare provider to determine which medication is right for you [2][3].

Sources:
[1] https://www.drugpatentwatch.com/p/tradename/LIPITOR
[2] https://www.mayoclinic.org/diseases-conditions/high-blood-cholesterol/in-depth/statins/art-20045772
[3] https://www.singlecare.com/blog/atorvastatin-vs-simvastatin/