Lipitor is a statin medication used to lower cholesterol levels in the body. Grapefruit and grapefruit juice can interfere with the metabolism of certain medications, including Lipitor, leading to potentially harmful side effects. According to GoodRx [2], patients taking Lipitor should avoid consuming grapefruit or grapefruit juice altogether, as it can increase the level of the drug in the bloodstream, leading to an increased risk of side effects such as muscle pain, liver damage, and kidney failure. The Harvard Health Letter [3] recommends that patients taking statins like Lipitor avoid grapefruit and grapefruit juice for at least three days before and after taking the medication to avoid these potential side effects. According to Drug Patent Watch [1], Lipitor's patent expired in 2011, and the medication is now available as a generic drug, which may have different guidelines for grapefruit consumption. It is always important to consult with a healthcare provider about any potential interactions between medications and foods or supplements.

Sources:
[1] https://www.drugpatentwatch.com/p/tradename/LIPITOR
[2] https://www.goodrx.com/classes/statins/why-cant-i-have-grapefruit-with-my-statin
[3] https://www.health.harvard.edu/heart-health/grapefruit-juice-and-statins