Lipitor is a brand name for the drug atorvastatin, which is a type of statin used to lower cholesterol levels in the blood. According to Drug Patent Watch [1], Lipitor's active ingredient, atorvastatin, is not known to interact with oranges. However, it is important to note that grapefruit and its juice can interfere with the effectiveness of statins, including atorvastatin [2]. Grapefruit contains compounds that inhibit the enzyme responsible for breaking down statins in the body, leading to higher levels of the drug in the bloodstream. This can increase the risk of side effects, including muscle damage. Therefore, it is generally recommended to avoid grapefruit and its juice when taking statins.

A study published in the Journal of Clinical Lipidology [3] investigated the effects of orange juice on the pharmacokinetics of atorvastatin in healthy volunteers. The study found that drinking orange juice did not significantly affect the absorption, metabolism, or elimination of atorvastatin. Therefore, it is unlikely that eating oranges would affect the effectiveness of Lipitor.

In conclusion, based on the sources provided, there is no evidence to suggest that eating oranges would affect the effectiveness of Lipitor. However, it is important to avoid grapefruit and its juice when taking statins, including atorvastatin. As with any medication, it is important to follow the instructions of your healthcare provider and pharmacist.

Sources:
[1] https://www.drugpatentwatch.com/p/tradename/LIPITOR
[2] https://www.healthline.com/health/high-cholesterol/grapefruit-and-statins
[3] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3589309/