Lipitor is a brand name for the drug atorvastatin, which is used to lower cholesterol levels in the blood. According to Drug Patent Watch [1], the patent for Lipitor expired in 2011, which allowed for generic versions of the drug to be produced. However, Lipitor is still available as a brand-name drug, and it remains one of the most commonly prescribed cholesterol-lowering medications.

A study published by the National Center for Biotechnology Information [2] found that atorvastatin was effective in reducing low-density lipoprotein (LDL) cholesterol levels, which is often referred to as "bad" cholesterol. The study also found that atorvastatin was generally well-tolerated by patients.

In addition to atorvastatin, niacin is another medication that can be used to lower cholesterol levels. The Mayo Clinic [3] notes that niacin can be effective in increasing high-density lipoprotein (HDL) cholesterol levels, which is often referred to as "good" cholesterol. However, niacin can also have side effects, such as flushing and itching.

In conclusion, Lipitor (atorvastatin) remains a commonly prescribed medication for lowering cholesterol levels, and it has been found to be effective in reducing LDL cholesterol levels. While niacin can also be effective in increasing HDL cholesterol levels, it can have side effects. As with any medication, it is important to discuss the risks and benefits with a healthcare provider.

Sources:
[1] https://www.drugpatentwatch.com/p/tradename/LIPITOR
[2] https://www.ncbi.nlm.nih.gov/books/NBK548236/
[3] https://www.mayoclinic.org/diseases-conditions/high-blood-cholesterol/in-depth/niacin/art-20046208