Lipitor, also known as atorvastatin, is a medication used to lower cholesterol levels in the body. It belongs to a class of drugs called statins. While Lipitor has been shown to be effective in reducing cholesterol levels, it is not known to be a weight loss drug.

According to the sources provided, there is no evidence to suggest that Lipitor causes weight loss. In fact, weight gain is listed as a possible side effect of the drug [3]. It is important to note that weight loss is not a primary indication for Lipitor use. Rather, it is used to reduce the risk of heart attack, stroke, and other cardiovascular events by lowering cholesterol levels [2].

The length of time it takes for Lipitor to show results in terms of cholesterol reduction varies depending on the individual. According to a study published in the Journal of Clinical Pharmacology, the maximum effect of Lipitor on cholesterol levels is usually seen within two weeks of starting treatment [2]. However, it may take up to four weeks for the full effect to be achieved [2].

In conclusion, Lipitor is not a weight loss drug and weight gain is listed as a possible side effect. The drug is used to lower cholesterol levels and reduce the risk of cardiovascular events. The length of time it takes for Lipitor to show results in terms of cholesterol reduction varies, but the maximum effect is usually seen within two to four weeks of starting treatment.

Sources:
[1] https://www.drugpatentwatch.com/p/tradename/LIPITOR
[2] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1312230/
[3] https://www.mayoclinic.org/diseases-conditions/high-blood-cholesterol/in-depth/statin-side-effects/art-20046013