Lipitor is a brand name for the drug atorvastatin, which is a statin used to lower cholesterol levels in the body. Grapefruit juice is known to interact with certain medications, including some statins. According to [2], grapefruit juice can increase the level of Lipitor in the blood, which can increase the risk of side effects. The interaction occurs because grapefruit juice inhibits an enzyme that is responsible for breaking down Lipitor in the body. This can cause Lipitor to stay in the body longer and at higher levels than intended. As a result, the risk of side effects, such as muscle pain and liver damage, may increase.

[3] recommends that patients taking Lipitor should avoid drinking grapefruit juice or eating grapefruit. If a patient is unable to avoid grapefruit, they should talk to their doctor about adjusting their medication dosage or switching to a different medication. Patients should also inform their doctor if they experience any side effects while taking Lipitor, as this may indicate that the medication is not being metabolized properly.

In conclusion, grapefruit juice can interact with Lipitor by increasing the level of the drug in the blood, which can increase the risk of side effects. Patients taking Lipitor should avoid consuming grapefruit juice or grapefruit and should talk to their doctor if they experience any side effects.

Sources:
[2] https://www.health.harvard.edu/heart-health/grapefruit-juice-and-statins
[3] https://www.verywellhealth.com/can-i-take-lipitor-or-zocor-with-grapefruit-juice-1124045