Lipitor (atorvastatin) is a medication that is used to lower cholesterol levels in the blood. It is not classified as a blood thinner, but rather as a statin drug [1]. Blood thinners, also known as anticoagulants, are medications that help prevent blood clots from forming. They work by interfering with the blood's ability to clot. Examples of blood thinners include warfarin, heparin, and dabigatran [2].

There is no evidence to suggest that Lipitor can decrease the effectiveness of blood thinners. In fact, there is no known interaction between Lipitor and blood thinners [1]. However, it is important to note that Lipitor can interact with other medications, such as some antibiotics and antifungal drugs, which can increase the risk of muscle damage [1].

It is also important to be aware of potential interactions between Lipitor and herbal supplements. Some herbal supplements, such as St. John's wort, can decrease the effectiveness of Lipitor, while others, such as garlic and ginkgo biloba, can increase the risk of bleeding when taken with blood thinners [3].

In conclusion, Lipitor is not a blood thinner and there is no evidence to suggest that it can decrease the effectiveness of blood thinners. However, it is important to talk to your healthcare provider about any medications or supplements you are taking to ensure that there are no potential interactions or risks involved.

Sources:
[1] DrugPatentWatch. (n.d.). Lipitor. Retrieved from https://www.drugpatentwatch.com/p/tradename/LIPITOR
[2] SingleCare. (2021, June 15). Is Atorvastatin a Blood Thinner? Retrieved from https://www.singlecare.com/blog/is-atorvastatin-a-blood-thinner/
[3] Mayo Clinic. (2021, February 3). Herbal supplements: What to know before you buy. Retrieved from https://www.mayoclinic.org/healthy-lifestyle/consumer-health/in-depth/herbal-supplements/art-20046488