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 patent expired in 2011, and it is now available as a generic drug.

Grapefruit juice contains compounds that can interfere with the way certain medications are metabolized in the body, including statins like Lipitor. According to Harvard Health Publishing [2], grapefruit juice can increase the amount of atorvastatin in the blood, leading to a higher risk of side effects. This is because grapefruit juice inhibits an enzyme in the liver that is responsible for breaking down atorvastatin and other drugs.

GoodRx [3] explains that the interaction between grapefruit juice and atorvastatin can lead to an increased risk of muscle pain and damage, as well as liver damage. Therefore, it is recommended that people taking Lipitor or other statins avoid consuming grapefruit or grapefruit juice.

In conclusion, consuming grapefruit can affect the effectiveness of Lipitor by increasing the amount of the drug in the bloodstream and potentially leading to harmful side effects. It is important for individuals taking Lipitor to avoid consuming grapefruit or grapefruit juice to ensure the safe and effective use of the medication.

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