Lipitor is a brand name for the drug atorvastatin, which is a type of medication used to lower cholesterol levels in the blood [1]. According to the Mayo Clinic, routine blood tests are typically recommended to monitor liver function before starting treatment with Lipitor, and periodic monitoring may be necessary thereafter [3]. However, the frequency of liver function tests may vary depending on individual patient factors and the prescribing physician's discretion [2].

The National Center for Biotechnology Information states that periodic liver function tests are recommended for patients taking atorvastatin, especially during the first few months of treatment, to monitor for potential liver damage [2]. The frequency of these tests may vary depending on the patient's age, medical history, and other factors, and may be adjusted based on the results of previous tests [2].

Overall, while routine liver function tests are typically recommended before and during treatment with Lipitor, the frequency of these tests may vary depending on individual patient factors and the prescribing physician's discretion. It is important for patients to discuss any concerns or questions about monitoring liver function with their healthcare provider [3].

Sources:
[1] https://www.drugpatentwatch.com/p/tradename/LIPITOR
[2] https://www.ncbi.nlm.nih.gov/books/NBK548236/
[3] https://www.mayoclinic.org/diseases-conditions/high-blood-cholesterol/in-depth/statin-side-effects/art-20046013