Lipitor is a medication that is used to lower cholesterol levels in the body. According to Drug Patent Watch [1], the active ingredient in Lipitor is atorvastatin calcium. Grapefruit juice is known to interact with some medications, including Lipitor. According to the FDA [2], grapefruit juice can cause an increase in the amount of Lipitor that is absorbed by the body, which can lead to an increased risk of side effects. This is because grapefruit juice contains compounds that inhibit the enzymes that break down Lipitor in the body.

A study published in the Journal of Clinical Lipidology [3] investigated the effects of grapefruit juice on the pharmacokinetics of atorvastatin, the active ingredient in Lipitor. The study found that grapefruit juice increased the bioavailability of atorvastatin by approximately 80%. This increase in bioavailability could potentially lead to an increased risk of side effects.

In conclusion, grapefruit juice can interact with Lipitor and increase the risk of side effects. Therefore, it is recommended that patients taking Lipitor avoid consuming grapefruit juice. Patients should also consult with their healthcare provider about any potential interactions between Lipitor and other medications or supplements they may be taking.

Sources:
[1] https://www.drugpatentwatch.com/p/tradename/LIPITOR
[2] https://www.fda.gov/consumers/consumer-updates/grapefruit-juice-and-some-drugs-dont-mix
[3] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3589309/