Lipitor is a brand name for atorvastatin, which is a medication used to lower cholesterol levels in the blood. The drug works by inhibiting an enzyme in the liver that is responsible for producing cholesterol. According to the sources provided, there is no evidence to suggest that Lipitor affects protein absorption.

The first source, Drug Patent Watch [1], provides information on the patent status of Lipitor and its generic equivalents. While it does not contain any information on the drug's effects on protein absorption, it is a useful resource for understanding the legal status of the medication.

The second source, a book chapter from the National Center for Biotechnology Information [2], provides an overview of atorvastatin and its mechanism of action. The chapter explains that the drug works by inhibiting the HMG-CoA reductase enzyme, which is involved in cholesterol synthesis. However, there is no mention of any effects on protein absorption.

The third source, a PubMed article [3], discusses the effects of atorvastatin on skeletal muscle in patients with high cholesterol. The study found that atorvastatin did not have a significant effect on muscle protein synthesis or breakdown. While this study is not directly related to protein absorption, it suggests that Lipitor does not have a significant impact on muscle protein metabolism.

In conclusion, based on the sources provided, there is no evidence to suggest that Lipitor affects protein absorption. The drug's primary mechanism of action is to inhibit cholesterol synthesis by inhibiting the HMG-CoA reductase enzyme in the liver. While there is some research on the effects of atorvastatin on muscle protein metabolism, there is no evidence to suggest that the drug has a significant impact on protein absorption.

Sources:
[1] https://www.drugpatentwatch.com/p/tradename/LIPITOR
[2] https://www.ncbi.nlm.nih.gov/books/NBK430779/
[3] https://pubmed.ncbi.nlm.nih.gov/14531725/