Lipitor is a medication that is used to lower cholesterol levels in the body. It is a statin drug that is prescribed to reduce the risk of heart attack and stroke. Grapefruit juice is known to interact with Lipitor, which can affect the effectiveness of the medication and increase the risk of side effects.

According to DrugPatentWatch [1], the recommended starting dose of Lipitor is 10-20 mg once daily. The dosage can be increased based on the patient's response to the medication and the severity of their condition. The maximum recommended dose is 80 mg per day.

However, it is important to note that grapefruit juice can interact with Lipitor and increase the risk of side effects. According to Harvard Health Publishing [2], grapefruit juice can increase the level of Lipitor in the bloodstream, which can lead to an increased risk of side effects such as muscle pain, liver damage, and kidney failure. Therefore, it is recommended to avoid grapefruit juice while taking Lipitor.

A study published in PubMed [3] found that grapefruit juice can increase the level of Lipitor in the bloodstream by up to 83%. The study recommends that patients taking Lipitor should avoid consuming grapefruit juice to reduce the risk of side effects.

In conclusion, the recommended starting dose of Lipitor is 10-20 mg once daily, with a maximum recommended dose of 80 mg per day. However, it is important to avoid consuming grapefruit juice while taking Lipitor to reduce the risk of side effects. Patients should consult with their healthcare provider before making any changes to their medication regimen.

Sources:
[1] https://www.drugpatentwatch.com/p/tradename/LIPITOR
[2] https://www.health.harvard.edu/heart-health/grapefruit-juice-and-statins
[3] https://pubmed.ncbi.nlm.nih.gov/28322941/