Lipitor is a brand name for the drug atorvastatin, which is a type of medication known as a statin. Statins are used to lower cholesterol levels in the blood. Grapefruit and grapefruit juice contain compounds that can interfere with the way the body metabolizes certain drugs, including statins like Lipitor. According to sources [2] and [3], consuming grapefruit or grapefruit juice while taking Lipitor can increase the levels of the drug in the bloodstream, which can increase the risk of side effects such as muscle pain and liver damage. Therefore, it is generally recommended that people taking Lipitor avoid consuming grapefruit or grapefruit juice. Source [2] suggests that the effect of grapefruit on Lipitor can last for up to 24 hours after consumption, so it is important to avoid grapefruit for the entire time that Lipitor is being taken. Source [1] confirms that Lipitor is indeed metabolized by the liver and that grapefruit juice inhibits the activity of an enzyme in the liver that is responsible for breaking down the drug. In summary, it is not recommended to consume grapefruit or grapefruit juice while taking Lipitor.

Sources:
[1] https://www.drugpatentwatch.com/p/tradename/LIPITOR
[2] https://www.verywellhealth.com/can-i-take-lipitor-or-zocor-with-grapefruit-juice-1124045
[3] https://www.goodrx.com/classes/statins/why-cant-i-have-grapefruit-with-my-statin