Lipitor, also known as atorvastatin, is a medication used to lower cholesterol levels in the body. According to the sources provided, the effectiveness of Lipitor can vary from person to person, and it may take several weeks or even months to see a significant change in cholesterol levels [1][2][3].

One of the sources states that Lipitor may start to lower cholesterol levels within two weeks of starting the medication [1]. However, the full effect of the drug may take up to four weeks or longer to become apparent. The drug works by blocking an enzyme in the liver that produces cholesterol, so it may take time for the body to adjust to the new levels of cholesterol production [2].

Another source suggests that it may take several months of consistent use for Lipitor to have a significant impact on cholesterol levels [3]. It is important to note that the effectiveness of the drug may also depend on other factors, such as the individual's diet and exercise habits.

In summary, the effectiveness of Lipitor can vary from person to person, and it may take several weeks or even months to see a significant change in cholesterol levels. While some individuals may start to see a difference within two weeks of starting the medication, it may take up to four weeks or longer for the full effect to become apparent. It is important to follow the prescribed dosage and maintain a healthy lifestyle to achieve the best results.

Sources:
[1] https://www.drugpatentwatch.com/p/tradename/LIPITOR
[2] https://www.healthline.com/health/drugs/lipitor
[3] https://www.singlecare.com/blog/lipitor-facts/