Lipitor (atorvastatin) is a medication used to lower cholesterol levels in the body [1]. St. John's wort (Hypericum perforatum) is a herbal supplement that is often used to treat depression, anxiety, and other mood disorders [2].

There is limited research on the interaction between Lipitor and St. John's wort. However, some studies suggest that St. John's wort may decrease the effectiveness of certain medications, including some cholesterol-lowering drugs [3]. This is because St. John's wort can increase the activity of enzymes in the liver that are responsible for breaking down drugs, which can lead to lower levels of the drug in the body [2].

It is important to note that St. John's wort can interact with many medications, including prescription drugs, over-the-counter medications, and herbal supplements. Therefore, it is important to talk to a healthcare provider before taking St. John's wort or any other herbal supplement, especially if you are taking prescription medications like Lipitor [3].

In conclusion, there is limited research on the interaction between Lipitor and St. John's wort. However, St. John's wort may decrease the effectiveness of certain medications, including some cholesterol-lowering drugs. Therefore, it is important to talk to a healthcare provider before taking St. John's wort or any other herbal supplement, especially if you are taking prescription medications like Lipitor [2][3].

Sources:
[1] https://www.drugpatentwatch.com/p/tradename/LIPITOR
[2] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3379774/
[3] https://www.herbalgram.org/resources/herbclip/issues/bin_339/review45121/