The frequency of liver tests while on Lipitor, a medication used to treat high cholesterol, can depend on various factors, including individual patient risk factors, the dosage of the medication, and the length of time on the medication.

According to the prescribing information for Lipitor, periodic liver function tests are recommended for patients at increased risk for liver disease, such as those with a history of heavy alcohol use or a history of liver disease. However, the frequency of these tests is not explicitly stated in the prescribing information.

In general, for patients on medications that have the potential to affect liver function, liver function tests may be performed at the start of treatment, after a certain period of time (such as 6-12 months), and then periodically thereafter. The specific frequency and timing of these tests will depend on the individual patient and the specific medication being used.

It is important for patients to discuss the need for liver function tests with their healthcare provider. Healthcare providers will consider a variety of factors when determining the appropriate frequency of liver function tests for a given patient.

In summary, the frequency of liver tests while on Lipitor may vary depending on individual patient risk factors and other considerations. It is important for patients to discuss the need for liver function tests with their healthcare provider.

Sources:

1. <https://www.accessdata.fda.gov/drugsatfda_docs/label/2016/202670s038lbl.pdf>
2. <https://www.drugpatentwatch.com/drugs/lipitor>