After analyzing the sources provided, there is no direct information about the effect of Lipitor on calcium absorption in skim milk. However, it is important to note that Lipitor is a medication used to lower cholesterol levels in the blood, and it is not known to interact with calcium or dairy products.

Calcium absorption is essential for bone health, and vitamin D plays a vital role in the absorption of calcium. The second source states that vitamin D is necessary for calcium absorption, and it can be obtained through diet, supplements, or sunlight exposure. The same source also notes that some medications, such as glucocorticoids and anticonvulsants, can interfere with vitamin D metabolism, leading to a decrease in calcium absorption.

The third source is the FDA label for Lipitor, which provides information about the medication's side effects, precautions, and interactions. However, there is no mention of any interaction between Lipitor and calcium absorption in skim milk.

In conclusion, based on the sources provided, there is no evidence to suggest that Lipitor affects calcium absorption in skim milk. It is important to maintain a balanced diet rich in calcium and vitamin D to promote bone health. If you have any concerns about the interaction between Lipitor and any other medications or supplements, it is recommended to consult with a healthcare provider.

Sources:
[1] https://www.drugpatentwatch.com/p/tradename/LIPITOR
[2] https://ods.od.nih.gov/factsheets/VitaminD-HealthProfessional/
[3] https://www.accessdata.fda.gov/drugsatfda_docs/label/2009/020702s056lbl.pdf