Lipitor is a medication used to lower cholesterol levels in the body. According to the drug patent watch [1], Lipitor's active ingredient is atorvastatin, which works by blocking an enzyme in the liver that produces cholesterol. This medication is effective in reducing LDL cholesterol, which is also known as "bad" cholesterol. The American Heart Association (AHA) [2] notes that atorvastatin is a potent cholesterol-lowering medication that can reduce LDL cholesterol levels by up to 60%. The AHA also reports that Lipitor is one of the most commonly prescribed cholesterol-lowering medications in the United States.

WebMD [3] states that statins, including Lipitor, are effective at lowering cholesterol levels quickly, often within two weeks. However, it is important to note that the effectiveness of Lipitor may vary from person to person, and it may take longer for some individuals to see a significant reduction in their cholesterol levels. Additionally, Lipitor is not a substitute for a healthy lifestyle, and individuals taking this medication should also make dietary and lifestyle changes to further reduce their cholesterol levels.

In conclusion, Lipitor (atorvastatin) is an effective medication for lowering cholesterol levels, particularly LDL cholesterol. It is a potent medication that can reduce cholesterol levels quickly, often within two weeks. However, the effectiveness of Lipitor may vary from person to person, and it is important to make dietary and lifestyle changes in addition to taking this medication to further reduce cholesterol levels.

Sources:
[1] https://www.drugpatentwatch.com/p/tradename/LIPITOR
[2] https://www.ahajournals.org/doi/full/10.1161/01.atv.15.5.678
[3] https://www.webmd.com/cholesterol-management/features/when-your-doctor-orders-cholesterol-lowering-medications