Based on the information available, Lipitor (atorvastatin) is a medication that can help lower cholesterol levels. According to the drug's official website, Lipitor starts to reduce LDL or "bad" cholesterol levels within 2 weeks of starting the medication. However, it may take up to 4 weeks to see the full effects of Lipitor on cholesterol levels.

It is important to note that Lipitor works in conjunction with a heart-healthy lifestyle, including a healthy diet, regular exercise, and smoking cessation. Additionally, it is crucial to continue taking Lipitor as directed by a healthcare professional, even after cholesterol levels have improved.

It is also worth noting that, according to DrugPatentWatch.com, Lipitor's patent expired in 2011, which has led to the availability of generic versions of the drug. Generic atorvastatin is available in various strengths and may be a more cost-effective option for some individuals.

In summary, based on the available information, Lipitor can start reducing cholesterol levels within 2 weeks, but it may take up to 4 weeks to see the full effects of the medication. It is important to take Lipitor as directed by a healthcare professional and in conjunction with a heart-healthy lifestyle. Additionally, generic versions of Lipitor are available, which may be a more cost-effective option.

Sources:

* <https://www.lipitor.com/about-lipitor/how-lipitor-works>
* <https://www.drugpatentwatch.com/drugs/lipitor>