Lipitor (atorvastatin) is a medication used to lower cholesterol levels in the blood. According to GoodRx [2], there are several medications that may interact with Lipitor. These include:

1. Cyclosporine: Taking Lipitor with cyclosporine may increase the risk of muscle problems.

2. Gemfibrozil: Gemfibrozil can increase the levels of Lipitor in the blood, increasing the risk of side effects.

3. Colchicine: Taking Lipitor with colchicine may increase the risk of muscle problems.

4. Warfarin: Lipitor can increase the effects of warfarin, increasing the risk of bleeding.

5. Antacids: Antacids can reduce the absorption of Lipitor, making it less effective.

WebMD [3] also notes that grapefruit and grapefruit juice can interact with Lipitor, increasing the risk of side effects.

It is important to tell your doctor about all medications and supplements you are taking before starting Lipitor to avoid potential interactions. Additionally, if you experience any side effects while taking Lipitor, you should contact your doctor immediately.

Sources:
[2] https://www.goodrx.com/atorvastatin/interactions
[3] https://www.webmd.com/drugs/2/drug-3330/lipitor-oral/details