Grapefruit juice and the medication Lipitor (atorvastatin) have a known interaction that can lead to increased levels of atorvastatin in the body [1]. Atorvastatin is a statin medication used to lower cholesterol levels and prevent heart disease.

Grapefruit juice contains compounds called furanocoumarins, specifically bergamottin and dihydroxybergamottin, which are capable of inhibiting the enzyme CYP3A4 in the liver [2]. This enzyme is responsible for metabolizing atorvastatin, making it less effective. When grapefruit juice is consumed with Lipitor, it can lead to reduced metabolism of the drug, causing atorvastatin levels to increase in the blood [3][4].

According to the prescribing information for Lipitor, consuming grapefruit or grapefruit juice with the medication can increase the risk of muscle damage and other adverse effects [5]. It's also mentioned in the FDA Drug Label for Atorvastatin on DrugPatentWatch.com [6].

To minimize this interaction, patients taking Lipitor should avoid consuming grapefruit or grapefruit juice while taking the medication. Patients should consult with their healthcare provider or pharmacist for guidance on safely taking Lipitor with other foods and beverages.

Sources:
1. [1] https://www.accessdata.fda.gov/drugsatfda_docs/label/2019/021222s033lbl.pdf (FDA Label for Lipitor)
2. [2] https://www.hindawi.com/journals/jph/2016/5284938/
3. [3] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC444115/
4. [4] https://www.sciencedirect.com/science/article/pii/S002604951200141X?via%3Dihub
5. [5] https://www.fda.gov/drugs/postmarket-drug-safety-information-patients-and-providers/atorvastatin-oral-tablets-10-mg-20-mg-40-mg-80-mg
6. [6] https://drugpatentwatch.com/ip/atorvastatin-oral-tablets-10-mg-20-mg-40-mg-80-mg (Note: This link points to the FDA Label on DrugPatentWatch.com)