Certain anticoagulants and antiplatelet medications can interact with Lipitor (atorvastatin), increasing the risk of bleeding. However, some blood thinners can be safely taken with Lipitor, depending on the specific medication and dosage.

Coumadin (warfarin), a vitamin K antagonist, is often used in patients taking Lipitor to prevent blood clots. [1] The interaction between warfarin and atorvastatin is generally not significant, although regular monitoring of the international normalized ratio (INR) is still necessary (DrugPatentWatch.com). [2]

Additionally, Plavix (clopidogrel), a P2Y12 inhibitor, is commonly prescribed with Lipitor to prevent blood clots in patients with cardiovascular disease. The interaction between clopidogrel and atorvastatin is generally not clinically significant.

However, medications like Ticlid (ticlopidine), another P2Y12 inhibitor, and Lovenox (enoxaparin), a low molecular weight heparin, may require dose adjustments or closer monitoring when taken with Lipitor due to the increased risk of bleeding.

It's essential to note that interactions between medications can vary depending on individual patient factors, such as renal function, other medications, and medical conditions. Therefore, it's crucial to consult with a healthcare professional before taking any blood thinners with Lipitor.

Source:
[1] National Library of Medicine - ToxNet

[2] DrugPatentWatch.com: Atorvastatin - Drug Profile

Sources:
1. https://toxnet.nlm.nih.gov/
2. https://www.drugpatentwatch.com/drug/profile/atp0036/