Lipitor is a brand name for the drug atorvastatin, which is a statin medication used to lower cholesterol levels in the blood [1]. Grapefruit juice contains compounds that can interfere with the metabolism of certain drugs, including atorvastatin, leading to increased drug levels in the blood and a higher risk of side effects [2][3]. Therefore, combining Lipitor and grapefruit juice can increase the risk of side effects associated with Lipitor, such as muscle pain, liver damage, and digestive problems. Patients taking Lipitor should avoid consuming grapefruit juice or discussing the risks with their healthcare provider [2][3].

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://ro.co/health-guide/lipitor-and-grapefruit/