Lipitor is a brand name for the drug atorvastatin, which is a medication used to lower cholesterol levels in the blood [1]. According to Drugwatch [3], Lipitor can be taken with or without food. However, the source does not mention anything about taking Lipitor with skim milk.

A study published in the Journal of Dairy Science suggests that consuming milk and dairy products, including skim milk, may interfere with the absorption of certain drugs, including atorvastatin [2]. The study found that taking atorvastatin with milk reduced its absorption by 32% compared to taking it with water. The study also suggested that the fat content in milk may be responsible for the reduced absorption of atorvastatin.

Therefore, it may be best to avoid taking Lipitor with skim milk or any other dairy products to ensure maximum absorption of the medication. It is important to consult with a healthcare professional before making any changes to medication regimens or diet.

Sources:
[1] https://www.drugpatentwatch.com/p/tradename/LIPITOR
[2] https://www.sciencedirect.com/science/article/pii/S2211383512000810
[3] https://www.drugwatch.com/lipitor/