Lipitor is a brand name for the drug atorvastatin, which is a type of statin used to lower cholesterol levels in the body. Fish oil supplements are commonly used to improve heart health and reduce inflammation.

According to a study published in the Journal of Clinical Lipidology [3], taking fish oil supplements did not affect the effectiveness of statins, including Lipitor. The study found that the combination of fish oil and statins was safe and well-tolerated in patients with high cholesterol levels.

Another study published in the American Journal of Cardiology [2] found that fish oil supplements were effective in reducing triglyceride levels, which are a type of fat in the blood that can contribute to heart disease. However, the study also found that statins were more effective in reducing LDL cholesterol levels, which is the "bad" cholesterol that can build up in the arteries and lead to heart disease.

While there is no evidence to suggest that taking fish oil supplements will negatively affect the effectiveness of Lipitor, it is always important to talk to your doctor before starting any new supplements or medications. Your doctor can help you determine the best course of treatment for your individual needs and monitor your progress to ensure that your cholesterol levels are well-controlled.

Sources:
[2] American Journal of Cardiology: https://www.ajconline.org/article/S0002-9149(12)01516-7/fulltext
[3] Journal of Clinical Lipidology: https://www.lipidjournal.com/article/S1933-2874(17)30247-3/fulltext
[1] Drug Patent Watch: https://www.drugpatentwatch.com/p/tradename/LIPITOR