Lipitor is a medication used to lower cholesterol levels in the body, and it is one of the most commonly prescribed drugs in the United States [1]. The active ingredient in Lipitor is atorvastatin, which works by inhibiting an enzyme in the liver that is responsible for producing cholesterol [2].

According to a study published in the Journal of Clinical Pharmacology, taking Lipitor with food does not significantly affect its effectiveness [3]. However, the study did not specifically address the question of whether taking Lipitor with skim milk reduces its effectiveness.

It is important to note that consuming certain foods, such as grapefruit juice, can interfere with the metabolism of Lipitor and increase the risk of side effects [2]. However, there is no evidence to suggest that skim milk has a similar effect.

In fact, a study conducted by researchers at Lawson Health Research Institute found that taking cholesterol medication with food, including milk, could actually reduce the risk of side effects such as muscle pain and weakness [4]. The study concluded that taking medication with food may help slow down the absorption of the drug, which could reduce the risk of adverse effects.

In summary, there is no evidence to suggest that taking Lipitor with skim milk reduces its effectiveness. However, it is important to follow the instructions provided by your healthcare provider and to avoid consuming certain foods that may interfere with the metabolism of the drug. Taking Lipitor with food, including skim milk, may actually help reduce the risk of side effects.

Sources:
[1] https://www.drugpatentwatch.com/p/tradename/LIPITOR
[2] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1312230/
[3] https://pubmed.ncbi.nlm.nih.gov/12036398/
[4] https://www.lawsonresearch.ca/news/taking-cholesterol-medication-food-could-reduce-risk-side-effects