Lipitor, also known as atorvastatin, is a medication used to treat high cholesterol levels. It belongs to a class of drugs called statins, which work by inhibiting the HMG-CoA reductase enzyme, thereby reducing the production of cholesterol in the body [1]. However, Lipitor's mechanism of action does not directly involve altering protein absorption.

Instead, Lipitor's primary function is to inhibit the enzyme responsible for cholesterol production, leading to a decrease in low-density lipoprotein (LDL), or "bad" cholesterol, and an increase in high-density lipoprotein (HDL), or "good" cholesterol [1].

It is important to note that Lipitor does not interact with proteins in the digestive tract to alter protein absorption. The drug is absorbed in the small intestine and undergoes first-pass metabolism in the liver, where it exerts its primary effects [2].

In summary, Lipitor does not alter protein absorption. Its primary function is to inhibit the HMG-CoA reductase enzyme, leading to a decrease in LDL cholesterol and an increase in HDL cholesterol.

Sources:

[1] Mayo Clinic. (2021). Atorvastatin (Oral Route). Retrieved from <https://www.mayoclinic.org/drugs-supplements/atorvastatin-oral-route/description/drg-20063084>

[2] DrugPatentWatch. (2021). Lipitor (Atorvastatin Calcium). Retrieved from <https://www.drugpatentwatch.com/drugs/lipitor>