Lipitor is a medication used to lower cholesterol levels in the body. According to the sources provided, the speed at which Lipitor works can vary depending on the individual and their specific medical situation.

Healthline [1] explains that Lipitor is designed to work gradually over time. The medication typically takes around two weeks to begin reducing cholesterol levels in the blood. However, the full effects of the medication may not be seen for up to four weeks. It is important to note that the speed at which Lipitor works can vary depending on the individual's starting cholesterol levels and other medical factors.

WebMD [2] notes that doctors may monitor a patient's cholesterol levels closely during the first few months of taking Lipitor to ensure that the medication is working effectively. If the medication is not producing the desired results, doctors may adjust the dosage or switch to a different medication.

Drug Patent Watch [3] provides additional information on the development and approval of Lipitor. The medication was first approved by the FDA in 1996 and has since become one of the most widely prescribed cholesterol-lowering medications in the world. Lipitor works by inhibiting an enzyme in the liver that is responsible for producing cholesterol.

In conclusion, Lipitor typically takes around two weeks to begin reducing cholesterol levels in the blood, with the full effects of the medication potentially taking up to four weeks. However, the speed at which Lipitor works can vary depending on the individual's starting cholesterol levels and other medical factors. It is important to work closely with a doctor to monitor the effectiveness of the medication and make any necessary adjustments to the dosage or treatment plan.

Sources:
[1] https://www.healthline.com/health/drugs/lipitor
[2] https://www.webmd.com/cholesterol-management/features/when-your-doctor-orders-cholesterol-lowering-medications
[3] https://www.drugpatentwatch.com/p/tradename/LIPITOR